how to change Java nio SSLBytechannel to ByteChannel - java

Hi have the code bellow that allows to upgrade a bytechannel to SSL.
Does anyone knows how to revert the process? I want to be able to upgrade or downgrade the java nio bytechannel, or change the channel without closing the socket.
Write now im using the following code to upgrade the byte channel. I ask you expertize to create an reverse function. Please.
//call
ByteChannel sslbytechannel = upgradeChannel2ServerSSLChannel(sourcebytechannel);
//function
private ByteChannel upgradeChannel2ServerSSLChannel(ByteChannel channel) {
try {
if (log.isLoggable(Level.FINE)) {
log.fine("Switching socket to SSL");
}
KeyStore ks = KeyStore.getInstance("JKS");
File kf = new File(getExproxy().getKeystoreFilename());
ks.load(new FileInputStream(kf), getExproxy().getKeystorePassword());
KeyManagerFactory kmf = KeyManagerFactory.getInstance("SunX509");
kmf.init(ks, getExproxy().getKeystoreKeysPassword());
TrustManagerFactory tmf = TrustManagerFactory.getInstance("SunX509");
tmf.init(ks);
SSLContext sslContext = SSLContext.getInstance("TLS");
sslContext.init(kmf.getKeyManagers(), tmf.getTrustManagers(), null);
SSLEngine engine = sslContext.createSSLEngine();
engine.setUseClientMode(false);
engine.beginHandshake();
return new SSLByteChannel(channel, engine);
} catch(Exception e) {
log.log(Level.SEVERE, "Exception during server SSL channel upgrade", e);
}
return null;
}
//Class
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ByteChannel;
import java.nio.channels.ClosedChannelException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.net.ssl.SSLEngine;
import javax.net.ssl.SSLEngineResult;
import javax.net.ssl.SSLException;
import java
x.net.ssl.SSLSession;
/**
* Upgrade a ByteChannel for SSL.
*
* <p>
* Change Log:
* </p>
* <ul>
* <li>v1.0.1 - Dead lock bug fix, take into account EOF during read and unwrap.</li>
* <li>v1.0.0 - First public release.</li>
* </ul>
*
* <p>
* This source code is given to the Public Domain. Do what you want with it.
* This software comes with no guarantees or warranties.
* Please visit http://perso.wanadoo.fr/reuse/sslbytechannel/
* periodically to check for updates or to contribute improvements.
* </p>
*
* #author David Crosson
* #author david.crosson#wanadoo.fr
* #version 1.0.0
*/
public class SSLByteChannel implements ByteChannel {
private ByteChannel wrappedChannel;
private boolean closed = false;
private SSLEngine engine;
private final ByteBuffer inAppData;
private final ByteBuffer outAppData;
private final ByteBuffer inNetData;
private final ByteBuffer outNetData;
private final Logger log = Logger.getLogger(getClass().getName());
/**
* Creates a new instance of SSLByteChannel
* #param wrappedChannel The byte channel on which this ssl channel is built.
* This channel contains encrypted data.
* #param engine A SSLEngine instance that will remember SSL current
* context. Warning, such an instance CAN NOT be shared
* between multiple SSLByteChannel.
*/
public SSLByteChannel(ByteChannel wrappedChannel, SSLEngine engine) {
this.wrappedChannel = wrappedChannel;
this.engine = engine;
SSLSession session = engine.getSession();
inAppData = ByteBuffer.allocate(session.getApplicationBufferSize());
outAppData = ByteBuffer.allocate(session.getApplicationBufferSize());
inNetData = ByteBuffer.allocate(session.getPacketBufferSize());
outNetData = ByteBuffer.allocate(session.getPacketBufferSize());
}
/**
* Ends SSL operation and close the wrapped byte channel
* #throws java.io.IOException May be raised by close operation on wrapped byte channel
*/
public void close() throws java.io.IOException {
if (!closed) {
try {
engine.closeOutbound();
sslLoop(wrap());
wrappedChannel.close();
} finally {
closed=true;
}
}
}
public SSLByteChannel(ByteChannel wrappedChannel) {
this.wrappedChannel = null;
this.engine = null;
inAppData = ByteBuffer.allocate(4096);
outAppData = ByteBuffer.allocate(4096);
inNetData = ByteBuffer.allocate(4096);
outNetData = ByteBuffer.allocate(4096);
}
/**
* Is the channel open ?
* #return true if the channel is still open
*/
public boolean isOpen() {
return !closed;
}
/**
* Fill the given buffer with some bytes and return the number of bytes
* added in the buffer.<br>
* This method may return immediately with nothing added in the buffer.
* This method must be use exactly in the same way of ByteChannel read
* operation, so be careful with buffer position, limit, ... Check
* corresponding javadoc.
* #param byteBuffer The buffer that will received read bytes
* #throws java.io.IOException May be raised by ByteChannel read operation
* #return The number of bytes read
*/
public int read(java.nio.ByteBuffer byteBuffer) throws java.io.IOException {
boolean eofDuringUnwrap = false;
if (isOpen()) {
try {
SSLEngineResult r = sslLoop(unwrap());
if (r==null) eofDuringUnwrap = true;
} catch(SSLException e) {
log.log(Level.SEVERE, "SSLException while reading", e);// TODO : Better SSL Exception management must be done
} catch(ClosedChannelException e) {
close();
}
}
inAppData.flip();
int posBefore = inAppData.position();
byteBuffer.put(inAppData);
int posAfter = inAppData.position();
inAppData.compact();
if (posAfter - posBefore > 0) return posAfter - posBefore ;
if (isOpen())
return (eofDuringUnwrap)?-1:0;
else
return -1;
}
/**
* Write remaining bytes of the given byte buffer.
* This method may return immediately with nothing written.
* This method must be use exactly in the same way of ByteChannel write
* operation, so be careful with buffer position, limit, ... Check
* corresponding javadoc.
* #param byteBuffer buffer with remaining bytes to write
* #throws java.io.IOException May be raised by ByteChannel write operation
* #return The number of bytes written
*/
public int write(java.nio.ByteBuffer byteBuffer) throws java.io.IOException {
if (!isOpen()) return 0;
int posBefore, posAfter;
posBefore = byteBuffer.position();
if (byteBuffer.remaining() < outAppData.remaining()) {
outAppData.put(byteBuffer); // throw a BufferOverflowException if byteBuffer.remaining() > outAppData.remaining()
} else {
while (byteBuffer.hasRemaining() && outAppData.hasRemaining()) {
outAppData.put(byteBuffer.get());
}
}
posAfter = byteBuffer.position();
if (isOpen()) {
try {
while(true) {
SSLEngineResult r = sslLoop(wrap());
if (r.bytesConsumed() == 0 && r.bytesProduced()==0) break;
};
} catch(SSLException e) {
log.log(Level.SEVERE, "SSLException while reading", e); // TODO : Better SSL Exception management must be done
} catch(ClosedChannelException e) {
close();
}
}
return posAfter - posBefore;
}
public void writeclean(java.nio.ByteBuffer byteBuffer) throws java.io.IOException {
if (isOpen()) {
try {
while(true) {
wrappedChannel.write(outAppData);
}
} catch(SSLException e) {
log.log(Level.SEVERE, "SSLException while reading", e); // TODO : Better SSL Exception management must be done
} catch(ClosedChannelException e) {
close();
}
}
}
private SSLEngineResult unwrap() throws IOException, SSLException {
int l;
while((l = wrappedChannel.read(inNetData)) > 0) {
try {
Thread.sleep(10); // Small tempo as non blocking channel is used
} catch(InterruptedException e) {
}
}
inNetData.flip();
if (l==-1 && !inNetData.hasRemaining()) return null;
SSLEngineResult ser = engine.unwrap(inNetData, inAppData);
inNetData.compact();
return ser;
}
private SSLEngineResult wrap() throws IOException, SSLException {
SSLEngineResult ser=null;
outAppData.flip();
ser = engine.wrap(outAppData, outNetData);
outAppData.compact();
outNetData.flip();
while(outNetData.hasRemaining()) {
int l = wrappedChannel.write(outNetData); // TODO : To be enhanced (potential deadlock ?)
try {
Thread.sleep(10); // Small tempo as non blocking channel is used
} catch(InterruptedException e) {
}
}
outNetData.compact();
return ser;
}
private SSLEngineResult sslLoop(SSLEngineResult ser) throws SSLException, IOException {
if (ser==null) return ser;
//log.finest(String.format("%s - %s\n", ser.getStatus().toString(), ser.getHandshakeStatus().toString()));
// System.out.println(String.format("%s - %s\n", ser.getStatus().toString(), ser.getHandshakeStatus().toString()));
while( ser.getHandshakeStatus() != SSLEngineResult.HandshakeStatus.FINISHED
&& ser.getHandshakeStatus() != SSLEngineResult.HandshakeStatus.NOT_HANDSHAKING) {
switch(ser.getHandshakeStatus()) {
case NEED_TASK:
//Executor exec = Executors.newSingleThreadExecutor();
Runnable task;
while ((task=engine.getDelegatedTask()) != null) {
//exec.execute(task);
task.run();
}
// Must continue with wrap as data must be sent
case NEED_WRAP:
ser = wrap();
break;
case NEED_UNWRAP:
ser = unwrap();
break;
}
if (ser == null) return ser;
}
switch(ser.getStatus()) {
case CLOSED:
log.finest("SSLEngine operations finishes, closing the socket");
try {
wrappedChannel.close();
} finally {
closed=true;
}
break;
}
return ser;
}
}

With regular HTTPS requests, you cannot start talking plain text, then switch to SSL, then back to plain text. You have to commit to either plain text or SSL mode of communication.
The only real life implementation that I can think of that allow upgrading plain text to SSL is STARTTLS with ESMTP. But even then you cannot downgrade back to plain text, once the SSL connection is established.
So, unless you are rolling your own server protocol, there is no real need for SSL downgrading.
EDIT
pseudo-code for falling back to unencrypted communication
ByteChannel sslByteChannel = upgradeChannel2ServerSSLChannel(sourceByteChannel);
try
{
doSslPortion( sslByteChannel );
doPlainPortion( sourceByteChannel );
}
finally
{
sourceByteChannel.close( );
}

Related

Encrypt/decrypt operation on a file produce strange effect on Android platform

I'm working on an Android application that needs to crypt (and then to decrypt) file on the file system. I wrote an android test to test the code that I found on the web and I adapted for my needed. I try with to crypt a simple text and then try to decrypt it. The problem is when I try to decrypt it, some strange character appears at the beginning of the content that I want to crypt/decrypt. For example, I try to crypt/decrypt a string like this:
Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)
And I received
X�­�YK�P���$BProgramming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)Concentration - Programming Music 0100 (Part 4)
The test code is
#Test
public void test() throws IOException, GeneralSecurityException {
String input = "Concentration - Programming Music 0100 (Part 4)";
for (int i=0;i<10;i++) {
input+=input;
}
String password = EncryptSystem.encrypt(new ByteArrayInputStream(input.getBytes(Charset.forName("UTF-8"))), new File(this.context.getFilesDir(), "test.txt"));
InputStream inputStream = EncryptSystem.decrypt(password, new File(this.context.getFilesDir(), "test.txt"));
//creating an InputStreamReader object
InputStreamReader isReader = new InputStreamReader(inputStream, Charset.forName("UTF-8"));
//Creating a BufferedReader object
BufferedReader reader = new BufferedReader(isReader);
StringBuilder sb = new StringBuilder();
String str;
while ((str = reader.readLine()) != null) {
sb.append(str);
}
System.out.println(sb.toString());
Assert.assertEquals(input, sb.toString());
}
The class code is:
import android.os.Build;
import android.os.Process;
import android.util.Base64;
import android.util.Log;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.security.*;
import java.util.Arrays;
import java.util.Objects;
import java.util.concurrent.atomic.AtomicBoolean;
import javax.crypto.*;
public class EncryptSystem {
public static class SecretKeys {
private SecretKey confidentialityKey;
private byte[] iv;
/**
* An aes key derived from a base64 encoded key. This does not generate the
* key. It's not random or a PBE key.
*
* #param keysStr a base64 encoded AES key / hmac key as base64(aesKey) : base64(hmacKey).
* #return an AES and HMAC key set suitable for other functions.
*/
public static SecretKeys of(String keysStr) throws InvalidKeyException {
String[] keysArr = keysStr.split(":");
if (keysArr.length != 2) {
throw new IllegalArgumentException("Cannot parse aesKey:iv");
} else {
byte[] confidentialityKey = Base64.decode(keysArr[0], BASE64_FLAGS);
if (confidentialityKey.length != AES_KEY_LENGTH_BITS / 8) {
throw new InvalidKeyException("Base64 decoded key is not " + AES_KEY_LENGTH_BITS + " bytes");
}
byte[] iv = Base64.decode(keysArr[1], BASE64_FLAGS);
/* if (iv.length != HMAC_KEY_LENGTH_BITS / 8) {
throw new InvalidKeyException("Base64 decoded key is not " + HMAC_KEY_LENGTH_BITS + " bytes");
}*/
return new SecretKeys(
new SecretKeySpec(confidentialityKey, 0, confidentialityKey.length, CIPHER),
iv);
}
}
public SecretKeys(SecretKey confidentialityKeyIn, byte[] i) {
setConfidentialityKey(confidentialityKeyIn);
iv = new byte[i.length];
System.arraycopy(i, 0, iv, 0, i.length);
}
public SecretKey getConfidentialityKey() {
return confidentialityKey;
}
public void setConfidentialityKey(SecretKey confidentialityKey) {
this.confidentialityKey = confidentialityKey;
}
#Override
public String toString() {
return Base64.encodeToString(getConfidentialityKey().getEncoded(), BASE64_FLAGS)
+ ":" + Base64.encodeToString(this.iv, BASE64_FLAGS);
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
SecretKeys that = (SecretKeys) o;
return confidentialityKey.equals(that.confidentialityKey) &&
Arrays.equals(iv, that.iv);
}
#Override
public int hashCode() {
int result = Objects.hash(confidentialityKey);
result = 31 * result + Arrays.hashCode(iv);
return result;
}
public byte[] getIv() {
return this.iv;
}
}
// If the PRNG fix would not succeed for some reason, we normally will throw an exception.
// If ALLOW_BROKEN_PRNG is true, however, we will simply log instead.
private static final boolean ALLOW_BROKEN_PRNG = false;
private static final String CIPHER_TRANSFORMATION = "AES/CBC/PKCS5Padding";
private static final String CIPHER = "AES";
private static final int AES_KEY_LENGTH_BITS = 128;
private static final int IV_LENGTH_BYTES = 16;
private static final int PBE_ITERATION_COUNT = 10000;
private static final int PBE_SALT_LENGTH_BITS = AES_KEY_LENGTH_BITS; // same size as key output
private static final String PBE_ALGORITHM = "PBKDF2WithHmacSHA1";
//Made BASE_64_FLAGS public as it's useful to know for compatibility.
public static final int BASE64_FLAGS = Base64.NO_WRAP;
//default for testing
static final AtomicBoolean prngFixed = new AtomicBoolean(false);
private static final String HMAC_ALGORITHM = "HmacSHA256";
private static final int HMAC_KEY_LENGTH_BITS = 256;
public static SecretKeys generateKey() throws GeneralSecurityException {
fixPrng();
KeyGenerator keyGen = KeyGenerator.getInstance(CIPHER);
// No need to provide a SecureRandom or set a seed since that will
// happen automatically.
keyGen.init(AES_KEY_LENGTH_BITS);
SecretKey confidentialityKey = keyGen.generateKey();
return new SecretKeys(confidentialityKey, generateIv());
}
private static void fixPrng() {
if (!prngFixed.get()) {
synchronized (PrngFixes.class) {
if (!prngFixed.get()) {
PrngFixes.apply();
prngFixed.set(true);
}
}
}
}
private static byte[] randomBytes(int length) throws GeneralSecurityException {
fixPrng();
SecureRandom random = new SecureRandom();
byte[] b = new byte[length];
random.nextBytes(b);
return b;
}
private static byte[] generateIv() throws GeneralSecurityException {
return randomBytes(IV_LENGTH_BYTES);
}
private static String keyString(SecretKeys keys) {
return keys.toString();
}
public static SecretKeys generateKeyFromPassword(String password, byte[] salt) throws GeneralSecurityException {
fixPrng();
//Get enough random bytes for both the AES key and the HMAC key:
KeySpec keySpec = new PBEKeySpec(password.toCharArray(), salt,
PBE_ITERATION_COUNT, AES_KEY_LENGTH_BITS + HMAC_KEY_LENGTH_BITS);
SecretKeyFactory keyFactory = SecretKeyFactory
.getInstance(PBE_ALGORITHM);
byte[] keyBytes = keyFactory.generateSecret(keySpec).getEncoded();
// Split the random bytes into two parts:
byte[] confidentialityKeyBytes = copyOfRange(keyBytes, 0, AES_KEY_LENGTH_BITS / 8);
byte[] integrityKeyBytes = copyOfRange(keyBytes, AES_KEY_LENGTH_BITS / 8, AES_KEY_LENGTH_BITS / 8 + HMAC_KEY_LENGTH_BITS / 8);
//Generate the AES key
SecretKey confidentialityKey = new SecretKeySpec(confidentialityKeyBytes, CIPHER);
return new SecretKeys(confidentialityKey, generateIv());
}
private static byte[] copyOfRange(byte[] from, int start, int end) {
int length = end - start;
byte[] result = new byte[length];
System.arraycopy(from, start, result, 0, length);
return result;
}
public static SecretKeys generateKeyFromPassword(String password, String salt) throws GeneralSecurityException {
return generateKeyFromPassword(password, Base64.decode(salt, BASE64_FLAGS));
}
public static String encrypt(InputStream inputStream, File fileToWrite)
throws GeneralSecurityException {
SecretKeys secretKeys = generateKey();
return encrypt(inputStream, secretKeys, fileToWrite);
}
public static InputStream decrypt(String secretKey, File fileToRead) throws InvalidKeyException, NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException, FileNotFoundException {
SecretKeys secretKeys = SecretKeys.of(secretKey);
Cipher aesCipherForDecryption = Cipher.getInstance(CIPHER_TRANSFORMATION);
aesCipherForDecryption.init(Cipher.DECRYPT_MODE, secretKeys.getConfidentialityKey(),
new IvParameterSpec(secretKeys.getIv()));
return new CipherInputStream(new FileInputStream(fileToRead), aesCipherForDecryption);
}
private static String encrypt(InputStream inputStream, SecretKeys secretKeys, File fileToWrite)
throws GeneralSecurityException {
byte[] iv = generateIv();
Cipher aesCipherForEncryption = Cipher.getInstance(CIPHER_TRANSFORMATION);
aesCipherForEncryption.init(Cipher.ENCRYPT_MODE, secretKeys.getConfidentialityKey(), new IvParameterSpec(iv));
saveFile(inputStream, aesCipherForEncryption, fileToWrite);
/*
* Now we get back the IV that will actually be used. Some Android
* versions do funny stuff w/ the IV, so this is to work around bugs:
*/
/*iv = aesCipherForEncryption.getIV();
//byte[] byteCipherText = aesCipherForEncryption.doFinal(plaintext);
byte[] ivCipherConcat = CipherTextIvMac.ivCipherConcat(iv, byteCipherText);
byte[] integrityMac = generateMac(ivCipherConcat, secretKeys.getIntegrityKey());
return new CipherTextIvMac(byteCipherText, iv, integrityMac);*/
return secretKeys.toString();
}
private static boolean saveFile(InputStream inputStream, Cipher aesCipherForEncryption, File fileToWrite) {
try {
OutputStream outputStream = null;
try {
byte[] fileReader = new byte[4096];
/*long fileSize = body.contentLength();*/
long fileSizeDownloaded = 0;
outputStream = new CipherOutputStream(new FileOutputStream(fileToWrite), aesCipherForEncryption);
while (true) {
int read = inputStream.read(fileReader);
if (read == -1) {
break;
}
outputStream.write(fileReader, 0, read);
fileSizeDownloaded += read;
}
outputStream.flush();
return true;
} catch (IOException e) {
e.printStackTrace();
return false;
} finally {
if (inputStream != null) {
inputStream.close();
}
if (outputStream != null) {
outputStream.close();
}
}
} catch (IOException e) {
return false;
}
}
public static final class PrngFixes {
private static final int VERSION_CODE_JELLY_BEAN = 16;
private static final int VERSION_CODE_JELLY_BEAN_MR2 = 18;
private static final byte[] BUILD_FINGERPRINT_AND_DEVICE_SERIAL = getBuildFingerprintAndDeviceSerial();
/**
* Hidden constructor to prevent instantiation.
*/
private PrngFixes() {
}
/**
* Applies all fixes.
*
* #throws SecurityException if a fix is needed but could not be
* applied.
*/
public static void apply() {
applyOpenSSLFix();
installLinuxPRNGSecureRandom();
}
/**
* Applies the fix for OpenSSL PRNG having low entropy. Does nothing if
* the fix is not needed.
*
* #throws SecurityException if the fix is needed but could not be
* applied.
*/
private static void applyOpenSSLFix() throws SecurityException {
if ((Build.VERSION.SDK_INT < VERSION_CODE_JELLY_BEAN)
|| (Build.VERSION.SDK_INT > VERSION_CODE_JELLY_BEAN_MR2)) {
// No need to apply the fix
return;
}
try {
// Mix in the device- and invocation-specific seed.
Class.forName("org.apache.harmony.xnet.provider.jsse.NativeCrypto")
.getMethod("RAND_seed", byte[].class).invoke(null, generateSeed());
// Mix output of Linux PRNG into OpenSSL's PRNG
int bytesRead = (Integer) Class
.forName("org.apache.harmony.xnet.provider.jsse.NativeCrypto")
.getMethod("RAND_load_file", String.class, long.class)
.invoke(null, "/dev/urandom", 1024);
if (bytesRead != 1024) {
throw new IOException("Unexpected number of bytes read from Linux PRNG: "
+ bytesRead);
}
} catch (Exception e) {
if (ALLOW_BROKEN_PRNG) {
Log.w(PrngFixes.class.getSimpleName(), "Failed to seed OpenSSL PRNG", e);
} else {
throw new SecurityException("Failed to seed OpenSSL PRNG", e);
}
}
}
/**
* Installs a Linux PRNG-backed {#code SecureRandom} implementation as
* the default. Does nothing if the implementation is already the
* default or if there is not need to install the implementation.
*
* #throws SecurityException if the fix is needed but could not be
* applied.
*/
private static void installLinuxPRNGSecureRandom() throws SecurityException {
if (Build.VERSION.SDK_INT > VERSION_CODE_JELLY_BEAN_MR2) {
// No need to apply the fix
return;
}
// Install a Linux PRNG-based SecureRandom implementation as the
// default, if not yet installed.
Provider[] secureRandomProviders = Security.getProviders("SecureRandom.SHA1PRNG");
// Insert and check the provider atomically.
// The official Android Java libraries use synchronized methods for
// insertProviderAt, etc., so synchronizing on the class should
// make things more stable, and prevent race conditions with other
// versions of this code.
synchronized (java.security.Security.class) {
if ((secureRandomProviders == null)
|| (secureRandomProviders.length < 1)
|| (!secureRandomProviders[0].getClass().getSimpleName().equals("LinuxPRNGSecureRandomProvider"))) {
Security.insertProviderAt(new PrngFixes.LinuxPRNGSecureRandomProvider(), 1);
}
// Assert that new SecureRandom() and
// SecureRandom.getInstance("SHA1PRNG") return a SecureRandom backed
// by the Linux PRNG-based SecureRandom implementation.
SecureRandom rng1 = new SecureRandom();
if (!rng1.getProvider().getClass().getSimpleName().equals("LinuxPRNGSecureRandomProvider")) {
if (ALLOW_BROKEN_PRNG) {
Log.w(PrngFixes.class.getSimpleName(),
"new SecureRandom() backed by wrong Provider: " + rng1.getProvider().getClass());
return;
} else {
throw new SecurityException("new SecureRandom() backed by wrong Provider: "
+ rng1.getProvider().getClass());
}
}
SecureRandom rng2 = null;
try {
rng2 = SecureRandom.getInstance("SHA1PRNG");
} catch (NoSuchAlgorithmException e) {
if (ALLOW_BROKEN_PRNG) {
Log.w(PrngFixes.class.getSimpleName(), "SHA1PRNG not available", e);
return;
} else {
new SecurityException("SHA1PRNG not available", e);
}
}
if (!rng2.getProvider().getClass().getSimpleName().equals("LinuxPRNGSecureRandomProvider")) {
if (ALLOW_BROKEN_PRNG) {
Log.w(PrngFixes.class.getSimpleName(),
"SecureRandom.getInstance(\"SHA1PRNG\") backed by wrong" + " Provider: "
+ rng2.getProvider().getClass());
return;
} else {
throw new SecurityException(
"SecureRandom.getInstance(\"SHA1PRNG\") backed by wrong" + " Provider: "
+ rng2.getProvider().getClass());
}
}
}
}
/**
* {#code Provider} of {#code SecureRandom} engines which pass through
* all requests to the Linux PRNG.
*/
private static class LinuxPRNGSecureRandomProvider extends Provider {
public LinuxPRNGSecureRandomProvider() {
super("LinuxPRNG", 1.0, "A Linux-specific random number provider that uses"
+ " /dev/urandom");
// Although /dev/urandom is not a SHA-1 PRNG, some apps
// explicitly request a SHA1PRNG SecureRandom and we thus need
// to prevent them from getting the default implementation whose
// output may have low entropy.
put("SecureRandom.SHA1PRNG", PrngFixes.LinuxPRNGSecureRandom.class.getName());
put("SecureRandom.SHA1PRNG ImplementedIn", "Software");
}
}
/**
* {#link SecureRandomSpi} which passes all requests to the Linux PRNG (
* {#code /dev/urandom}).
*/
public static class LinuxPRNGSecureRandom extends SecureRandomSpi {
/*
* IMPLEMENTATION NOTE: Requests to generate bytes and to mix in a
* seed are passed through to the Linux PRNG (/dev/urandom).
* Instances of this class seed themselves by mixing in the current
* time, PID, UID, build fingerprint, and hardware serial number
* (where available) into Linux PRNG.
*
* Concurrency: Read requests to the underlying Linux PRNG are
* serialized (on sLock) to ensure that multiple threads do not get
* duplicated PRNG output.
*/
private static final File URANDOM_FILE = new File("/dev/urandom");
private static final Object sLock = new Object();
/**
* Input stream for reading from Linux PRNG or {#code null} if not
* yet opened.
*
* #GuardedBy("sLock")
*/
private static DataInputStream sUrandomIn;
/**
* Output stream for writing to Linux PRNG or {#code null} if not
* yet opened.
*
* #GuardedBy("sLock")
*/
private static OutputStream sUrandomOut;
/**
* Whether this engine instance has been seeded. This is needed
* because each instance needs to seed itself if the client does not
* explicitly seed it.
*/
private boolean mSeeded;
#Override
protected void engineSetSeed(byte[] bytes) {
try {
OutputStream out;
synchronized (sLock) {
out = getUrandomOutputStream();
}
out.write(bytes);
out.flush();
} catch (IOException e) {
// On a small fraction of devices /dev/urandom is not
// writable Log and ignore.
Log.w(PrngFixes.class.getSimpleName(), "Failed to mix seed into "
+ URANDOM_FILE);
} finally {
mSeeded = true;
}
}
#Override
protected void engineNextBytes(byte[] bytes) {
if (!mSeeded) {
// Mix in the device- and invocation-specific seed.
engineSetSeed(generateSeed());
}
try {
DataInputStream in;
synchronized (sLock) {
in = getUrandomInputStream();
}
synchronized (in) {
in.readFully(bytes);
}
} catch (IOException e) {
throw new SecurityException("Failed to read from " + URANDOM_FILE, e);
}
}
#Override
protected byte[] engineGenerateSeed(int size) {
byte[] seed = new byte[size];
engineNextBytes(seed);
return seed;
}
private DataInputStream getUrandomInputStream() {
synchronized (sLock) {
if (sUrandomIn == null) {
// NOTE: Consider inserting a BufferedInputStream
// between DataInputStream and FileInputStream if you need
// higher PRNG output performance and can live with future PRNG
// output being pulled into this process prematurely.
try {
sUrandomIn = new DataInputStream(new FileInputStream(URANDOM_FILE));
} catch (IOException e) {
throw new SecurityException("Failed to open " + URANDOM_FILE
+ " for reading", e);
}
}
return sUrandomIn;
}
}
private OutputStream getUrandomOutputStream() throws IOException {
synchronized (sLock) {
if (sUrandomOut == null) {
sUrandomOut = new FileOutputStream(URANDOM_FILE);
}
return sUrandomOut;
}
}
}
/**
* Generates a device- and invocation-specific seed to be mixed into the
* Linux PRNG.
*/
private static byte[] generateSeed() {
try {
ByteArrayOutputStream seedBuffer = new ByteArrayOutputStream();
DataOutputStream seedBufferOut = new DataOutputStream(seedBuffer);
seedBufferOut.writeLong(System.currentTimeMillis());
seedBufferOut.writeLong(System.nanoTime());
seedBufferOut.writeInt(Process.myPid());
seedBufferOut.writeInt(Process.myUid());
seedBufferOut.write(BUILD_FINGERPRINT_AND_DEVICE_SERIAL);
seedBufferOut.close();
return seedBuffer.toByteArray();
} catch (IOException e) {
throw new SecurityException("Failed to generate seed", e);
}
}
/**
* Gets the hardware serial number of this device.
*
* #return serial number or {#code null} if not available.
*/
private static String getDeviceSerialNumber() {
// We're using the Reflection API because of Build.SERIAL is only
// available since API Level 9 (Gingerbread, Android 2.3).
try {
return (String) Build.class.getField("SERIAL").get(null);
} catch (Exception ignored) {
return null;
}
}
private static byte[] getBuildFingerprintAndDeviceSerial() {
StringBuilder result = new StringBuilder();
String fingerprint = Build.FINGERPRINT;
if (fingerprint != null) {
result.append(fingerprint);
}
String serial = getDeviceSerialNumber();
if (serial != null) {
result.append(serial);
}
try {
return result.toString().getBytes("UTF-8");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException("UTF-8 encoding not supported");
}
}
}
}
Any idea about what I'm in wrong? Thank you in advance
Finally, I solve by myself. I post the solution just to help anybody that in the future will look for a similar situation. I mistake to retrieve the iv array in the encrypt method, I was generating another iv vector instead of using the one contained in secretKeys.
private static String encrypt(InputStream inputStream, SecretKeys secretKeys, File fileToWrite)
throws GeneralSecurityException {
Cipher aesCipherForEncryption = Cipher.getInstance(CIPHER_TRANSFORMATION);
aesCipherForEncryption.init(Cipher.ENCRYPT_MODE, secretKeys.getConfidentialityKey(), new IvParameterSpec(secretKeys.getIv()));
saveFile(inputStream, aesCipherForEncryption, fileToWrite);
return secretKeys.toString();
}

Discontinuous FTP download throws "Read timed out" or "Connection reset"

I used FTP and FTPClient in package 'org.apache.commons.net.ftp' to download files from FTP server.
Here is my total example code
public class FtpInput {
private static final Logger LOG = Logger.getLogger(FtpInput.class);
private static final int TIMEOUT = 120000;
private static final String SIZE_COMMAND_REPLY_CODE = "213 ";
/**
* FTPClient
*/
private FTPClient ftpClient;
/**
* FTP size
*/
private long completeFileSize = 0;
protected String ip = "";
protected int port = 21;
protected String user = "";
protected String passwd = "";
protected String path = "";
protected String fileName = "";
/**
* count input bytes
*/
private CountingInputStream is;
/**
* the bytes already processed
*/
private long processedBytesNum;
private byte[] inputBuffer = new byte[1024];
/**
* connect to ftp server and fetch inputStream
*/
public void connect() {
this.ftpClient = new FTPClient();
ftpClient.setRemoteVerificationEnabled(false);
try {
ftpClient.connect(ip, port);
if (!ftpClient.login(user, passwd)) {
throw new IOException("ftp login failed!");
}
if (StringUtils.isNotBlank(path)) {
if (!ftpClient.changeWorkingDirectory(path)) {
ftpClient.mkd(path);
if (!ftpClient.changeWorkingDirectory(path)) {
throw new IOException("ftp change working dir failed! path:" + path);
}
}
}
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
ftpClient.setSoTimeout(TIMEOUT);
ftpClient.setConnectTimeout(TIMEOUT);
ftpClient.setDataTimeout(TIMEOUT);
ftpClient.enterLocalPassiveMode();
// keep control channel keep-alive when download large file
ftpClient.setControlKeepAliveTimeout(120);
} catch (Throwable e) {
e.printStackTrace();
throw new RuntimeException("ftp login failed!", e);
}
// get complete ftp size
completeFileSize = getFtpFileSize();
LOG.info(String.format("ftp file size: %d", completeFileSize));
try {
InputStream ftpis = this.ftpClient.retrieveFileStream(this.fileName);
if (ftpis == null) {
LOG.error("cannot fetch source file.");
}
this.is = new CountingInputStream(ftpis);
} catch (Throwable e) {
e.printStackTrace();
throw new RuntimeException(e.getMessage());
}
}
/**
* readBytes
*
* #return
*/
public byte[] readBytes() {
byte[] bytes = readBytesFromStream(is, inputBuffer);
// the bytes processed
processedBytesNum = is.getCount();
return bytes;
}
/**
* readBytesFromStream
*
* #param stream
* #param inputBuffer
* #return
*/
protected byte[] readBytesFromStream(InputStream stream, byte[] inputBuffer) {
Preconditions.checkNotNull(stream != null, "InputStream has not been inited yet.");
Preconditions.checkArgument(inputBuffer != null && inputBuffer.length > 0);
int readBytes;
try {
readBytes = stream.read(inputBuffer);
} catch (IOException e) {
throw new RuntimeException(e);
}
if (readBytes == inputBuffer.length) {
// inputBuffer is filled full.
return inputBuffer;
} else if (readBytes > 0 && readBytes < inputBuffer.length) {
// inputBuffer is not filled full.
byte[] tmpBytes = new byte[readBytes];
System.arraycopy(inputBuffer, 0, tmpBytes, 0, readBytes);
return tmpBytes;
} else if (readBytes == -1) {
// Read end.
return null;
} else {
// may other situation happens?
throw new RuntimeException(String.format("readBytesFromStream: readBytes=%s inputBuffer.length=%s",
readBytes, inputBuffer.length));
}
}
/**
* fetch the byte size of remote file size
*/
private long getFtpFileSize() {
try {
ftpClient.sendCommand("SIZE", this.fileName);
String reply = ftpClient.getReplyString().trim();
LOG.info(String.format("ftp file %s size reply : %s", fileName, reply));
Preconditions.checkArgument(reply.startsWith(SIZE_COMMAND_REPLY_CODE),
"ftp file size reply: %s is not success", reply);
String sizeSubStr = reply.substring(SIZE_COMMAND_REPLY_CODE.length());
long actualFtpSize = Long.parseLong(sizeSubStr);
return actualFtpSize;
} catch (Throwable e) {
e.printStackTrace();
throw new RuntimeException(e.getMessage());
}
}
public void close() {
try {
if (is != null) {
LOG.info(String.format("already read %d bytes from ftp file %s", is.getCount(), fileName));
is.close();
}
if (ftpClient != null) {
// Must call completePendingCommand() to finish command.
boolean isSuccessTransfer = ftpClient.completePendingCommand();
if (!isSuccessTransfer) {
LOG.error("error happened when complete transfer of ftp");
}
ftpClient.logout();
ftpClient.disconnect();
}
} catch (Throwable e) {
e.printStackTrace();
LOG.error(String.format("Close ftp input failed:%s,%s", e.getMessage(), e.getCause()));
} finally {
is = null;
ftpClient = null;
}
}
public void validInputComplete() {
Preconditions.checkArgument(processedBytesNum == completeFileSize, "ftp file transfer is not complete");
}
/**
* main
*
* #param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
String ip = "***.***.***.****";
int port = 21;
String user = "***";
String passwd = "***";
String path = "/home/work";
String fileName = "b.txt";
FtpInput input = new FtpInput();
try {
input.fileName = fileName;
input.path = path;
input.ip = ip;
input.port = port;
input.user = user;
input.passwd = passwd;
// connect to FTP server
input.connect();
while (true) {
// read bytes
byte[] bytes = input.readBytes();
if (bytes == null) {
break;
}
LOG.info("read " + bytes.length + " bytes at :" + new Date(System.currentTimeMillis()));
// Attention: this is used for simulating the process of writing data into hive table
// it maybe consume more than 1 minute;
Thread.sleep(3000);
}
input.validInputComplete();
} catch (Exception e) {
e.printStackTrace();
} finally {
input.close();
}
}
}
here is the exception message:
java.net.SocketTimeoutException: Read timed out
or
java.net.SocketException: Connection reset
at stream.readBytes in method readBytesFromStream
At first, i think it probably caused by writing into hive table slowly, and then the FTP Server closed the connection.
But actually, the speed of writing into hive table is fast enough.
Now, i need your help, how can i fix this problem.
From your comments, it looks like it can take hours before you finish downloading the file.
You cannot reasonably expect an FTP server to wait for you for hours to finish the transfer. Particularly if you are not transferring anything most of the time. You waste server resources and most servers will protect themselves against such abuse.
Your design is flawed.
You should redesign your application to first fully download the file; and import the file only after the download finishes.

How to encode images into a video file in Java through programming?

I am trying to encode some images of same resolution into a video file using, For that I have tried:
jCodec
jcodec..example description
But it is very time consuming and not a proper tool to encode large number of images and it creates a quick time extension.
FFMPEG
FFMPEG..example description
But ffmpeg only able to create video from image files. Images need to be create on physical system.
I have heard Xuggler that its APIs can be used in java program to create video file but as its site seems broken. I am unable to try it.
Does anybody know how to encode images in java format into a video file Please help!
THanks in Advance !
Xuggler is deprecated, use Humble-Video instead. It already comes with some demo projects, including how to take screenshots and convert it to a video file: RecordAndEncodeVideo.java
/*******************************************************************************
* Copyright (c) 2014, Art Clarke. All rights reserved.
* <p>
* This file is part of Humble-Video.
* <p>
* Humble-Video is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
* <p>
* Humble-Video is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
* <p>
* You should have received a copy of the GNU Affero General Public License
* along with Humble-Video. If not, see <http://www.gnu.org/licenses/>.
*******************************************************************************/
package io.humble.video.demos;
import io.humble.video.*;
import io.humble.video.awt.MediaPictureConverter;
import io.humble.video.awt.MediaPictureConverterFactory;
import org.apache.commons.cli.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
/**
* Records the contents of your computer screen to a media file for the passed in duration.
* This is meant as a demonstration program to teach the use of the Humble API.
* <p>
* Concepts introduced:
* </p>
* <ul>
* <li>Muxer: A {#link Muxer} object is a container you can write media data to.</li>
* <li>Encoders: An {#link Encoder} object lets you convert {#link MediaAudio} or {#link MediaPicture} objects into {#link MediaPacket} objects
* so they can be written to {#link Muxer} objects.</li>
* </ul>
*
* <p>
* To run from maven, do:
* </p>
* <pre>
* mvn install exec:java -Dexec.mainClass="io.humble.video.demos.RecordAndEncodeVideo" -Dexec.args="filename.mp4"
* </pre>
*
* #author aclarke
*
*/
public class RecordAndEncodeVideo
{
/**
* Records the screen
*/
private static void recordScreen (String filename, String formatname, String codecname, int duration, int snapsPerSecond) throws AWTException, InterruptedException, IOException
{
/**
* Set up the AWT infrastructure to take screenshots of the desktop.
*/
final Robot robot = new Robot();
final Toolkit toolkit = Toolkit.getDefaultToolkit();
final Rectangle screenbounds = new Rectangle(toolkit.getScreenSize());
final Rational framerate = Rational.make(1, snapsPerSecond);
/** First we create a muxer using the passed in filename and formatname if given. */
final Muxer muxer = Muxer.make(filename, null, formatname);
/** Now, we need to decide what type of codec to use to encode video. Muxers
* have limited sets of codecs they can use. We're going to pick the first one that
* works, or if the user supplied a codec name, we're going to force-fit that
* in instead.
*/
final MuxerFormat format = muxer.getFormat();
final Codec codec;
if (codecname != null)
{
codec = Codec.findEncodingCodecByName(codecname);
}
else
{
codec = Codec.findEncodingCodec(format.getDefaultVideoCodecId());
}
/**
* Now that we know what codec, we need to create an encoder
*/
Encoder encoder = Encoder.make(codec);
/**
* Video encoders need to know at a minimum:
* width
* height
* pixel format
* Some also need to know frame-rate (older codecs that had a fixed rate at which video files could
* be written needed this). There are many other options you can set on an encoder, but we're
* going to keep it simpler here.
*/
encoder.setWidth(screenbounds.width);
encoder.setHeight(screenbounds.height);
// We are going to use 420P as the format because that's what most video formats these days use
final PixelFormat.Type pixelformat = PixelFormat.Type.PIX_FMT_YUV420P;
encoder.setPixelFormat(pixelformat);
encoder.setTimeBase(framerate);
/** An annoynace of some formats is that they need global (rather than per-stream) headers,
* and in that case you have to tell the encoder. And since Encoders are decoupled from
* Muxers, there is no easy way to know this beyond
*/
if (format.getFlag(MuxerFormat.Flag.GLOBAL_HEADER))
{
encoder.setFlag(Encoder.Flag.FLAG_GLOBAL_HEADER, true);
}
/** Open the encoder. */
encoder.open(null, null);
/** Add this stream to the muxer. */
muxer.addNewStream(encoder);
/** And open the muxer for business. */
muxer.open(null, null);
/** Next, we need to make sure we have the right MediaPicture format objects
* to encode data with. Java (and most on-screen graphics programs) use some
* variant of Red-Green-Blue image encoding (a.k.a. RGB or BGR). Most video
* codecs use some variant of YCrCb formatting. So we're going to have to
* convert. To do that, we'll introduce a MediaPictureConverter object later. object.
*/
MediaPictureConverter converter = null;
final MediaPicture picture = MediaPicture.make(encoder.getWidth(), encoder.getHeight(), pixelformat);
picture.setTimeBase(framerate);
/** Now begin our main loop of taking screen snaps.
* We're going to encode and then write out any resulting packets. */
final MediaPacket packet = MediaPacket.make();
for (int i = 0; i < duration / framerate.getDouble(); i++)
{
/** Make the screen capture && convert image to TYPE_3BYTE_BGR */
final BufferedImage screen = convertToType(robot.createScreenCapture(screenbounds), BufferedImage.TYPE_3BYTE_BGR);
/** This is LIKELY not in YUV420P format, so we're going to convert it using some handy utilities. */
if (converter == null)
{
converter = MediaPictureConverterFactory.createConverter(screen, picture);
}
converter.toPicture(picture, screen, i);
do
{
encoder.encode(packet, picture);
if (packet.isComplete())
{
muxer.write(packet, false);
}
} while (packet.isComplete());
/** now we'll sleep until it's time to take the next snapshot. */
Thread.sleep((long) (1000 * framerate.getDouble()));
}
/** Encoders, like decoders, sometimes cache pictures so it can do the right key-frame optimizations.
* So, they need to be flushed as well. As with the decoders, the convention is to pass in a null
* input until the output is not complete.
*/
do
{
encoder.encode(packet, null);
if (packet.isComplete())
{
muxer.write(packet, false);
}
} while (packet.isComplete());
/** Finally, let's clean up after ourselves. */
muxer.close();
}
#SuppressWarnings("static-access")
public static void main (String[] args) throws InterruptedException, IOException, AWTException
{
final Options options = new Options();
options.addOption("h", "help", false, "displays help");
options.addOption("v", "version", false, "version of this library");
options.addOption(OptionBuilder.withArgName("format").withLongOpt("format").hasArg().
withDescription("muxer format to use. If unspecified, we will guess from filename").create("f"));
options.addOption(OptionBuilder.withArgName("codec")
.withLongOpt("codec")
.hasArg()
.withDescription("codec to use when encoding video; If unspecified, we will guess from format")
.create("c"));
options.addOption(OptionBuilder.withArgName("duration")
.withLongOpt("duration")
.hasArg()
.withDescription("number of seconds of screenshot to record; defaults to 10.")
.create("d"));
options.addOption(OptionBuilder.withArgName("snaps per second")
.withLongOpt("snaps")
.hasArg()
.withDescription("number of pictures to take per second (i.e. the frame rate); defaults to 5")
.create("s"));
final CommandLineParser parser = new org.apache.commons.cli.BasicParser();
try
{
final CommandLine cmd = parser.parse(options, args);
final String[] parsedArgs = cmd.getArgs();
if (cmd.hasOption("version"))
{
// let's find what version of the library we're running
final String version = io.humble.video_native.Version.getVersionInfo();
System.out.println("Humble Version: " + version);
}
else if (cmd.hasOption("help") || parsedArgs.length != 1)
{
final HelpFormatter formatter = new HelpFormatter();
formatter.printHelp(RecordAndEncodeVideo.class.getCanonicalName() + " <filename>", options);
}
else
{
/**
* Read in some option values and their defaults.
*/
final int duration = Integer.parseInt(cmd.getOptionValue("duration", "10"));
if (duration <= 0)
{
throw new IllegalArgumentException("duration must be > 0");
}
final int snaps = Integer.parseInt(cmd.getOptionValue("snaps", "5"));
if (snaps <= 0)
{
throw new IllegalArgumentException("snaps must be > 0");
}
final String codecname = cmd.getOptionValue("codec");
final String formatname = cmd.getOptionValue("format");
final String filename = cmd.getArgs()[0];
recordScreen(filename, formatname, codecname, duration, snaps);
}
} catch (ParseException e)
{
System.err.println("Exception parsing command line: " + e.getLocalizedMessage());
}
}
/**
* Convert a {#link BufferedImage} of any type, to {#link BufferedImage} of a
* specified type. If the source image is the same type as the target type,
* then original image is returned, otherwise new image of the correct type is
* created and the content of the source image is copied into the new image.
*
* #param sourceImage
* the image to be converted
* #param targetType
* the desired BufferedImage type
*
* #return a BufferedImage of the specifed target type.
*
* #see BufferedImage
*/
public static BufferedImage convertToType (BufferedImage sourceImage, int targetType)
{
BufferedImage image;
// if the source image is already the target type, return the source image
if (sourceImage.getType() == targetType)
{
image = sourceImage;
}
// otherwise create a new image of the target type and draw the new
// image
else
{
image = new BufferedImage(sourceImage.getWidth(), sourceImage.getHeight(), targetType);
image.getGraphics().drawImage(sourceImage, 0, 0, null);
}
return image;
}
}
Check other demos too : humble-video-demos
I am using it for real time using on a webapp.
If you will gonna stream this in real time you will need a RTSP server. You can either use big frameworks like Red 5 Server, Wowza Streaming Engine or you can built your own server using Netty which has a built in RTSP codec since version 3.2.
Using command line, there are various ways to convert image to video. You can use those command in java for saving. You can get those commands from the following link:
Using ffmpeg to convert a set of images into a video
Create a video slideshow from images
I am sharing a code snippet to solve the issue:
code to save png image from HTML5 canvas
Base64 decoder = new Base64();
byte[] pic = decoder.decodeBase64(request.getParameter("pic"));
String frameCount = request.getParameter("frame");
InputStream in = new ByteArrayInputStream(pic);
BufferedImage bImageFromConvert = ImageIO.read(in);
String outdir = "output\\"+frameCount;
//Random rand = new Random();
File file = new File(outdir);
if(file.isFile()){
if(file.delete()){
File writefile = new File(outdir);
ImageIO.write(bImageFromConvert, "png", file);
}
}
Code for creating image from video
String filePath = "D:\\temp\\some.mpg";
String outdir = "output";
File file = new File(outdir);
file.mkdirs();
Map<String, String> m = System.getenv();
/*
* String command[] =
* {"D:\\ffmpeg-win32-static\\bin\\ffmpeg","-i",filePath
* ,"-r 30","-f","image2",outdir,"\\user%03d.jpg"};
*
* ProcessBuilder pb = new ProcessBuilder(command); pb.start();
*/
String commands = "D:\\ffmpeg-win32-static\\bin\\ffmpeg -i " + filePath
+ " -r 30 -f image2 " + outdir + "\\image%5d.png";
Process p = Runtime.getRuntime().exec(commands);
code for creating video from image
String filePath = "output";
File fileP = new File(filePath);
String commands = "D:\\ffmpeg-win32-static\\bin\\ffmpeg -f image2 -i "
+ fileP + "\\image%5d.png " + fileP + "\\video.mp4";
System.out.println(commands);
Runtime.getRuntime().exec(commands);
System.out.println(fileP.getAbsolutePath());
Credit goes to #yashprit
Another approach for Android developers:
Create a temporary folder inside the Android.
Copy your images in the new folder
First, rename your pictures to follow a numerical sequence. For
example, img1.jpg, img2.jpg, img3.jpg,... Then you may run:
Run this program programmetcally ffmpeg -f image2 -i img%d.jpg
/tmp/a.mpg To run this programmatically,
Use the following code:
void convertImg_to_vid()
{
Process chperm;
try {
chperm=Runtime.getRuntime().exec("su");
DataOutputStream os =
new DataOutputStream(chperm.getOutputStream());
os.writeBytes("ffmpeg -f image2 -i img%d.jpg /tmp/a.mpg\n");
os.flush();
chperm.waitFor();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Resource Link:
Create a Video file from images using ffmpeg
There is a utility in Java Media Framework which, It can create Video from List of Jpeg Images Link
Here is the source code:
JpegImagesToMovie.java
/*
* #(#)JpegImagesToMovie.java 1.3 01/03/13
* Copyright (c) 1999-2001 Sun Microsystems, Inc. All Rights Reserved.
* Sun grants you ("Licensee") a non-exclusive, royalty free, license to use,
* modify and redistribute this software in source and binary code form,
* provided that i) this copyright notice and license appear on all copies of
* the software; and ii) Licensee does not utilize the software in a manner
* which is disparaging to Sun.
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY
* IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR
* NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE
* LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING
* OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS
* LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT,
* INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER
* CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF
* OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* This software is not designed or intended for use in on-line control of
* aircraft, air traffic, aircraft navigation or aircraft communications; or in
* the design, construction, operation or maintenance of any nuclear
* facility. Licensee represents and warrants that it will not use or
* redistribute the Software for such purposes.
*/
package imagetovideo;
import java.awt.Dimension;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.MalformedURLException;
import java.util.Vector;
import javax.media.Buffer;
import javax.media.ConfigureCompleteEvent;
import javax.media.ControllerEvent;
import javax.media.ControllerListener;
import javax.media.DataSink;
import javax.media.EndOfMediaEvent;
import javax.media.Format;
import javax.media.Manager;
import javax.media.MediaLocator;
import javax.media.PrefetchCompleteEvent;
import javax.media.Processor;
import javax.media.RealizeCompleteEvent;
import javax.media.ResourceUnavailableEvent;
import javax.media.Time;
import javax.media.control.TrackControl;
import javax.media.datasink.DataSinkErrorEvent;
import javax.media.datasink.DataSinkEvent;
import javax.media.datasink.DataSinkListener;
import javax.media.datasink.EndOfStreamEvent;
import javax.media.format.VideoFormat;
import javax.media.protocol.ContentDescriptor;
import javax.media.protocol.DataSource;
import javax.media.protocol.FileTypeDescriptor;
import javax.media.protocol.PullBufferDataSource;
import javax.media.protocol.PullBufferStream;
/**
* This program takes a list of JPEG image files and convert them into a
* QuickTime movie.
*/
public class JpegImagesToMovie implements ControllerListener, DataSinkListener {
public boolean doIt(int width, int height, int frameRate, Vector inFiles,
MediaLocator outML) throws MalformedURLException {
ImageDataSource ids = new ImageDataSource(width, height, frameRate,
inFiles);
Processor p;
try {
//System.err
// .println("- create processor for the image datasource ...");
p = Manager.createProcessor(ids);
} catch (Exception e) {
System.err
.println("Yikes! Cannot create a processor from the data source.");
return false;
}
p.addControllerListener(this);
// Put the Processor into configured state so we can set
// some processing options on the processor.
p.configure();
if (!waitForState(p, p.Configured)) {
System.err.println("Failed to configure the processor.");
return false;
}
// Set the output content descriptor to QuickTime.
p.setContentDescriptor(new ContentDescriptor(
FileTypeDescriptor.QUICKTIME));
// Query for the processor for supported formats.
// Then set it on the processor.
TrackControl tcs[] = p.getTrackControls();
Format f[] = tcs[0].getSupportedFormats();
if (f == null || f.length <= 0) {
System.err.println("The mux does not support the input format: "
+ tcs[0].getFormat());
return false;
}
tcs[0].setFormat(f[0]);
//System.err.println("Setting the track format to: " + f[0]);
// We are done with programming the processor. Let's just
// realize it.
p.realize();
if (!waitForState(p, p.Realized)) {
System.err.println("Failed to realize the processor.");
return false;
}
// Now, we'll need to create a DataSink.
DataSink dsink;
if ((dsink = createDataSink(p, outML)) == null) {
System.err
.println("Failed to create a DataSink for the given output MediaLocator: "
+ outML);
return false;
}
dsink.addDataSinkListener(this);
fileDone = false;
System.out.println("Generating the video : "+outML.getURL().toString());
// OK, we can now start the actual transcoding.
try {
p.start();
dsink.start();
} catch (IOException e) {
System.err.println("IO error during processing");
return false;
}
// Wait for EndOfStream event.
waitForFileDone();
// Cleanup.
try {
dsink.close();
} catch (Exception e) {
}
p.removeControllerListener(this);
System.out.println("Video creation completed!!!!!");
return true;
}
/**
* Create the DataSink.
*/
DataSink createDataSink(Processor p, MediaLocator outML) {
DataSource ds;
if ((ds = p.getDataOutput()) == null) {
System.err
.println("Something is really wrong: the processor does not have an output DataSource");
return null;
}
DataSink dsink;
try {
//System.err.println("- create DataSink for: " + outML);
dsink = Manager.createDataSink(ds, outML);
dsink.open();
} catch (Exception e) {
System.err.println("Cannot create the DataSink: " + e);
return null;
}
return dsink;
}
Object waitSync = new Object();
boolean stateTransitionOK = true;
/**
* Block until the processor has transitioned to the given state. Return
* false if the transition failed.
*/
boolean waitForState(Processor p, int state) {
synchronized (waitSync) {
try {
while (p.getState() < state && stateTransitionOK)
waitSync.wait();
} catch (Exception e) {
}
}
return stateTransitionOK;
}
/**
* Controller Listener.
*/
public void controllerUpdate(ControllerEvent evt) {
if (evt instanceof ConfigureCompleteEvent
|| evt instanceof RealizeCompleteEvent
|| evt instanceof PrefetchCompleteEvent) {
synchronized (waitSync) {
stateTransitionOK = true;
waitSync.notifyAll();
}
} else if (evt instanceof ResourceUnavailableEvent) {
synchronized (waitSync) {
stateTransitionOK = false;
waitSync.notifyAll();
}
} else if (evt instanceof EndOfMediaEvent) {
evt.getSourceController().stop();
evt.getSourceController().close();
}
}
Object waitFileSync = new Object();
boolean fileDone = false;
boolean fileSuccess = true;
/**
* Block until file writing is done.
*/
boolean waitForFileDone() {
synchronized (waitFileSync) {
try {
while (!fileDone)
waitFileSync.wait();
} catch (Exception e) {
}
}
return fileSuccess;
}
/**
* Event handler for the file writer.
*/
public void dataSinkUpdate(DataSinkEvent evt) {
if (evt instanceof EndOfStreamEvent) {
synchronized (waitFileSync) {
fileDone = true;
waitFileSync.notifyAll();
}
} else if (evt instanceof DataSinkErrorEvent) {
synchronized (waitFileSync) {
fileDone = true;
fileSuccess = false;
waitFileSync.notifyAll();
}
}
}
/*public static void main(String args[]) {
if (args.length == 0)
prUsage();
// Parse the arguments.
int i = 0;
int width = -1, height = -1, frameRate = 1;
Vector inputFiles = new Vector();
String outputURL = null;
while (i < args.length) {
if (args[i].equals("-w")) {
i++;
if (i >= args.length)
prUsage();
width = new Integer(args[i]).intValue();
} else if (args[i].equals("-h")) {
i++;
if (i >= args.length)
prUsage();
height = new Integer(args[i]).intValue();
} else if (args[i].equals("-f")) {
i++;
if (i >= args.length)
prUsage();
frameRate = new Integer(args[i]).intValue();
} else if (args[i].equals("-o")) {
i++;
if (i >= args.length)
prUsage();
outputURL = args[i];
} else {
inputFiles.addElement(args[i]);
}
i++;
}
if (outputURL == null || inputFiles.size() == 0)
prUsage();
// Check for output file extension.
if (!outputURL.endsWith(".mov") && !outputURL.endsWith(".MOV")) {
System.err
.println("The output file extension should end with a .mov extension");
prUsage();
}
if (width < 0 || height < 0) {
System.err.println("Please specify the correct image size.");
prUsage();
}
// Check the frame rate.
if (frameRate < 1)
frameRate = 1;
// Generate the output media locators.
MediaLocator oml;
if ((oml = createMediaLocator(outputURL)) == null) {
System.err.println("Cannot build media locator from: " + outputURL);
System.exit(0);
}
JpegImagesToMovie imageToMovie = new JpegImagesToMovie();
imageToMovie.doIt(width, height, frameRate, inputFiles, oml);
System.exit(0);
}*/
static void prUsage() {
System.err
.println("Usage: java JpegImagesToMovie -w <width> -h <height> -f <frame rate> -o <output URL> <input JPEG file 1> <input JPEG file 2> ...");
System.exit(-1);
}
/**
* Create a media locator from the given string.
*/
static MediaLocator createMediaLocator(String url) {
MediaLocator ml;
if (url.indexOf(":") > 0 && (ml = new MediaLocator(url)) != null)
return ml;
if (url.startsWith(File.separator)) {
if ((ml = new MediaLocator("file:" + url)) != null)
return ml;
} else {
String file = "file:" + System.getProperty("user.dir")
+ File.separator + url;
if ((ml = new MediaLocator(file)) != null)
return ml;
}
return null;
}
// /////////////////////////////////////////////
//
// Inner classes.
// /////////////////////////////////////////////
/**
* A DataSource to read from a list of JPEG image files and turn that into a
* stream of JMF buffers. The DataSource is not seekable or positionable.
*/
class ImageDataSource extends PullBufferDataSource {
ImageSourceStream streams[];
ImageDataSource(int width, int height, int frameRate, Vector images) {
streams = new ImageSourceStream[1];
streams[0] = new ImageSourceStream(width, height, frameRate, images);
}
public void setLocator(MediaLocator source) {
}
public MediaLocator getLocator() {
return null;
}
/**
* Content type is of RAW since we are sending buffers of video frames
* without a container format.
*/
public String getContentType() {
return ContentDescriptor.RAW;
}
public void connect() {
}
public void disconnect() {
}
public void start() {
}
public void stop() {
}
/**
* Return the ImageSourceStreams.
*/
public PullBufferStream[] getStreams() {
return streams;
}
/**
* We could have derived the duration from the number of frames and
* frame rate. But for the purpose of this program, it's not necessary.
*/
public Time getDuration() {
return DURATION_UNKNOWN;
}
public Object[] getControls() {
return new Object[0];
}
public Object getControl(String type) {
return null;
}
}
/**
* The source stream to go along with ImageDataSource.
*/
class ImageSourceStream implements PullBufferStream {
Vector images;
int width, height;
VideoFormat format;
int nextImage = 0; // index of the next image to be read.
boolean ended = false;
public ImageSourceStream(int width, int height, int frameRate,
Vector images) {
this.width = width;
this.height = height;
this.images = images;
format = new VideoFormat(VideoFormat.JPEG, new Dimension(width,
height), Format.NOT_SPECIFIED, Format.byteArray,
(float) frameRate);
}
/**
* We should never need to block assuming data are read from files.
*/
public boolean willReadBlock() {
return false;
}
/**
* This is called from the Processor to read a frame worth of video
* data.
*/
public void read(Buffer buf) throws IOException {
// Check if we've finished all the frames.
if (nextImage >= images.size()) {
// We are done. Set EndOfMedia.
//System.err.println("Done reading all images.");
buf.setEOM(true);
buf.setOffset(0);
buf.setLength(0);
ended = true;
return;
}
String imageFile = (String) images.elementAt(nextImage);
nextImage++;
//System.err.println(" - reading image file: " + imageFile);
// Open a random access file for the next image.
RandomAccessFile raFile;
raFile = new RandomAccessFile(imageFile, "r");
byte data[] = null;
// Check the input buffer type & size.
if (buf.getData() instanceof byte[])
data = (byte[]) buf.getData();
// Check to see the given buffer is big enough for the frame.
if (data == null || data.length < raFile.length()) {
data = new byte[(int) raFile.length()];
buf.setData(data);
}
// Read the entire JPEG image from the file.
raFile.readFully(data, 0, (int) raFile.length());
//System.err.println(" read " + raFile.length() + " bytes.");
buf.setOffset(0);
buf.setLength((int) raFile.length());
buf.setFormat(format);
buf.setFlags(buf.getFlags() | buf.FLAG_KEY_FRAME);
// Close the random access file.
raFile.close();
}
/**
* Return the format of each video frame. That will be JPEG.
*/
public Format getFormat() {
return format;
}
public ContentDescriptor getContentDescriptor() {
return new ContentDescriptor(ContentDescriptor.RAW);
}
public long getContentLength() {
return 0;
}
public boolean endOfStream() {
return ended;
}
public Object[] getControls() {
return new Object[0];
}
public Object getControl(String type) {
return null;
}
}
}
Its doIt function can be called from another class having main function:
CreatVideo.java
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package imagetovideo;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import java.net.MalformedURLException;
import java.util.Vector;
import javax.media.MediaLocator;
public class CreateVideo{
public static final File dir = new File("D:\\imagesFolder\\");
public static final String[] extensions = new String[]{"jpg", "png"};
public static final FilenameFilter imageFilter = new FilenameFilter() {
#Override
public boolean accept(final File dir, String name) {
for (final String ext : extensions) {
if (name.endsWith("." + ext)) {
return (true);
}
}
return (false);
}
};
// Main function
public static void main(String[] args) throws IOException {
File file = new File("D:\\a.mp4");
if (!file.exists()) {
file.createNewFile();
}
Vector<String> imgLst = new Vector<>();
if (dir.isDirectory()) {
int counter = 1;
for (final File f : dir.listFiles(imageFilter)) {
imgLst.add(f.getAbsolutePath());
}
}
makeVideo("file:\\" + file.getAbsolutePath(), imgLst);
}
public static void makeVideo(String fileName, Vector imgLst) throws MalformedURLException {
JpegImagesToMovie imageToMovie = new JpegImagesToMovie();
MediaLocator oml;
if ((oml = imageToMovie.createMediaLocator(fileName)) == null) {
System.err.println("Cannot build media locator from: " + fileName);
System.exit(0);
}
int interval = 40;
imageToMovie.doIt(720, 360, (1000 / interval), imgLst, oml);
}
}
Requirements:
Include jmf-2.1.1e.jar in your Library Folder (using this library)

Java Client-Server and Observer

I am implementing a Java Client-Server application for a university task and I'm stuck at the following point: I am obliged to use client-server and also update the view whenever the data in the database changes. What I have done is that whenever a change in the database should occur I notify all the clients with the "CHANGE IN DATA" message and then the client should read and understand this message in order to call a method that will update it's graphic interface. However, or I'm mistaking the reading part on client side or because of some error, the clients don't read the "CHANGE IN DATA" message so the whole gets stuck at this point and the view doesn't update.
Here are some relevant codes!
Server class:
public class FinesPaymentServer implements Runnable {
private Database database;
private UserGateway userGateway;
private FineGateway fineGateway;
private DriverGateway driverGateway;
private Socket connection;
private int ID;
static ArrayList<Socket> clientsConnected;
/**
* Constructor of the class connecting to the database and initializing the socket
* #param database the database used
* #param connection the socket for the server
* #param ID the id
*/
private FinesPaymentServer(Database database, UserGateway userGateway, FineGateway fineGateway, DriverGateway driverGateway, Socket connection, int ID) {
this.connection = connection;
this.userGateway = userGateway;
this.fineGateway = fineGateway;
this.driverGateway = driverGateway;
this.database = database;
this.ID = ID;
}
/**
* Run method of the threads for each socket on the server
*/
public void run() {
try {
while(true)
readFromClient(connection);
} catch (IOException | SQLException e) {
System.out.println(e);
}
}
/**
* Read method from the client
* #param client the client socket from where to read
* #throws IOException
* #throws SQLException
*/
public void readFromClient(Socket client) throws IOException, SQLException {
BufferedInputStream is = new BufferedInputStream(client.getInputStream());
InputStreamReader reader = new InputStreamReader(is);
StringBuffer process = new StringBuffer();
int character;
while((character = reader.read()) != 13) {
process.append((char)character);
}
System.out.println("[SERVER READ]: "+process);
String[] words = process.toString().split("\\s+");
switch (process.charAt(0)) {
case 'a' :
{
int type = database.verifyLogin(words[1], words[2]);
sendMessage(client, ""+type + " ");
break;
}
case 'b' :
{
String rs = userGateway.getUsers();
sendMessage(client, rs);
break;
}
case 'c' :
{
userGateway.createUser(words[1], words[2], words[3]);
notifyClients();
break;
}
case 'd' :
{
userGateway.updateUser(words[1], words[2], words[3]);
notifyClients();
break;
}
case 'e' :
{
userGateway.deleteUser(words[1]);
notifyClients();
break;
}
}
try {
Thread.sleep(1000);
} catch (Exception e){}
String time_stamp = new java.util.Date().toString();
String returnCode = "Single Socket Server responded at " + time_stamp + (char) 13;
sendMessage(client, returnCode);
}
/**
* Method for sending messages from the server to the client
* #param client the client socket where to send the message
* #param message the message itself to be sent
* #throws IOException
*/
private void sendMessage(Socket client, String message) throws IOException {
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(client.getOutputStream()));
writer.write(message);
System.out.println("[SERVER WRITE]: "+message);
writer.flush();
}
public void notifyClients() throws IOException
{
for(Socket s : clientsConnected)
{
sendMessage(s, "CHANGE IN DATA ");
}
}
/**
* #param args the command line arguments
* #throws java.sql.SQLException
*/
public static void main(String[] args) throws SQLException {
Database database = new Database();
UserGateway userGateway = new UserGateway();
FineGateway fineGateway = new FineGateway();
DriverGateway driverGateway = new DriverGateway();
clientsConnected = new ArrayList<>();
// Setting a default port number.
int portNumber = 2015;
int count = 0;
System.out.println("Starting the multiple socket server at port: " + portNumber);
try {
ServerSocket serverSocket = new ServerSocket(portNumber);
System.out.println("Multiple Socket Server Initialized");
//Listen for clients
while(true) {
Socket client = serverSocket.accept();
clientsConnected.add(client);
Runnable runnable = new FinesPaymentServer(database, userGateway, fineGateway, driverGateway, client, ++count);
Thread thread = new Thread(runnable);
thread.start();
}
} catch (Exception e) {}
}
}
The client class:
public class FinesPaymentClient implements Runnable {
private String hostname = "localhost";
private int port = 2015;
Socket socketClient;
AdministratorModel adminModel;
PoliceModel policeModel;
PostModel postModel;
/**
* Constructor of the class
* #param hostname the host name of the connection
* #param port the port of the connection
* #throws UnknownHostException
* #throws IOException
*/
public FinesPaymentClient(String hostname, int port, AdministratorModel adminModel, PoliceModel policeModel, PostModel postModel) throws UnknownHostException, IOException
{
this.hostname = hostname;
this.port = port;
this.adminModel = adminModel;
this.policeModel = policeModel;
this.postModel = postModel;
connect();
}
/**
* Method for connecting to the host by a socket
* #throws UnknownHostException
* #throws IOException
*/
public void connect() throws UnknownHostException, IOException {
System.out.println("Attempting to connect to " + hostname + ":" + port);
socketClient = new Socket(hostname, port);
System.out.println("Connection Established");
}
/**
* Method for reading response from the server
* #return the string read from the server
* #throws IOException
*/
public String readResponse() throws IOException {
String userInput;
BufferedReader stdIn = new BufferedReader(
new InputStreamReader(socketClient.getInputStream()));
System.out.println("[CLIENT READ]:");
while ((userInput = stdIn.readLine()) != null) {
System.out.println(userInput);
return userInput;
}
return userInput;
}
/**
* Method for closing connection between client and server
* #throws IOException
*/
public void closeConnection() throws IOException {
socketClient.close();
}
/**
* Method for writing messages to the server
* #param message the message to be sent
* #throws IOException
*/
public void writeMessage(String message) throws IOException {
String time_stamp = new java.util.Date().toString();
// Please note that we placed a char(13) at the end of process...
// we use this to let the server know we are at the end
// of the data we are sending
String process = message + (char) 13;
BufferedWriter stdOut = new BufferedWriter(
new OutputStreamWriter(socketClient.getOutputStream()));
stdOut.write(process);
System.out.println("[CLIENT WRITE]: "+process);
// We need to flush the buffer to ensure that the data will be written
// across the socket in a timely manner
stdOut.flush();
}
#Override
public void run() {
try {
String response;
while(true)
{
response = readResponse();
System.out.println("HERE"+response.substring(0, 13));
if(response.substring(0, 13).equals("CHANGE IN DATA"))
{
adminModel.setChange();
}
}
} catch (IOException e) {
System.out.println(e);
}
}
/**
* Main method of the application
* #param arg the parameters given as arguments
* #throws SQLException
* #throws UnknownHostException
* #throws IOException
*/
public static void main(String arg[]) throws SQLException, UnknownHostException, IOException {
AdministratorModel adminModel = new AdministratorModel();
PoliceModel policeModel = new PoliceModel();
PostModel postModel = new PostModel();
FinesPaymentClient client = new FinesPaymentClient("localhost", 2015, adminModel, policeModel, postModel);
Runnable client2 = new FinesPaymentClient("localhost", 2015, adminModel, policeModel, postModel);
Thread thread = new Thread(client2);
thread.start();
Login login = new Login();
ClientSide clientSide = new ClientSide(login, client, adminModel, policeModel, postModel);
}
}
ClientSide class:
public class ClientSide {
private final Login login;
private FinesPaymentClient client;
AdministratorModel adminModel;
PoliceModel policeModel;
PostModel postModel;
/**
* Constructor instantiating needed classes
* #param login an instance of the login class
* #param client the client needing the control logic
* #param adminModel
* #param policeModel
* #param postModel
* #throws SQLException using classes connecting to a database sql exceptions can occur
*/
public ClientSide(Login login, FinesPaymentClient client, AdministratorModel adminModel, PoliceModel policeModel, PostModel postModel) throws SQLException
{
this.login = login;
this.client = client;
this.adminModel = adminModel;
this.policeModel = policeModel;
this.postModel = postModel;
login.addButtonListener(new ButtonListener());
}
/**
* Listener for the login button. Reads, verifies and provides the interface according to logged in user type.
*/
class ButtonListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
try
{
client.writeMessage("a " + login.field1.getText()+ " " + login.field2.getText());
String response = client.readResponse();
if(response.charAt(0) == '1')
{
login.setVisible(false);
AdministratorGUI administratorGUI = new AdministratorGUI(adminModel, client);
AdministratorController adminController = new AdministratorController(client, administratorGUI, adminModel);
}
//if user is post office employee
else if(response.charAt(0) == '2')
{
login.setVisible(false);
PostGUI postGUI = new PostGUI();
PostController postController = new PostController(client, postGUI, postModel);
}
//if user is police employee
else if(response.charAt(0) == '3')
{
login.setVisible(false);
PoliceGUI policeGUI = new PoliceGUI();
PoliceController policeController = new PoliceController(client, policeGUI, policeModel);
}
else
{
JOptionPane.showMessageDialog(null,"Login failed! Please try again!");
}
}
catch (IOException ex)
{
Logger.getLogger(ClientSide.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}
I'm 99% sure that the error is on client side reading the message sent from the server as notification, but I simply cannot figure it out how could I retrieve that message. Right now I have a try in the client threads run method, but doesn't work. Other classes and other functionalities work just fine, this is my only problem. Do you have any ideas what the mistake could be? I would appreciate any help.

Running a Client-Server Chat program

This is one of the most common application scenario that can be found all over the net. and I'm not asking any questions about the java codes that I did because I was successful in running it on my laptop where both the client and server part of the .java file resides. Rather I have had problem getting it to work in between two computers. I tried establishing physical connection using cross-over cable to connect two computers, and did a test to see if file transfers successfully and it did, however, keeping one Server part of the .java file in one computer and client part in the other, I tried to run the server first and then the client but it got a "access denied" error.
For reference here's my two .java files:
/* ChatClient.java */
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
public class ChatClient {
private static int port = 5000; /* port to connect to */
private static String host = "localhost"; /* host to connect to (server's IP)*/
private static BufferedReader stdIn;
private static String nick;
/**
* Read in a nickname from stdin and attempt to authenticate with the
* server by sending a NICK command to #out. If the response from #in
* is not equal to "OK" go bacl and read a nickname again
*/
private static String getNick(BufferedReader in,
PrintWriter out) throws IOException {
System.out.print("Enter your nick: ");
String msg = stdIn.readLine();
out.println("NICK " + msg);
String serverResponse = in.readLine();
if ("SERVER: OK".equals(serverResponse)) return msg;
System.out.println(serverResponse);
return getNick(in, out);
}
public static void main (String[] args) throws IOException {
Socket server = null;
try {
server = new Socket(host, port);
} catch (UnknownHostException e) {
System.err.println(e);
System.exit(1);
}
stdIn = new BufferedReader(new InputStreamReader(System.in));
/* obtain an output stream to the server... */
PrintWriter out = new PrintWriter(server.getOutputStream(), true);
/* ... and an input stream */
BufferedReader in = new BufferedReader(new InputStreamReader(
server.getInputStream()));
nick = getNick(in, out);
/* create a thread to asyncronously read messages from the server */
ServerConn sc = new ServerConn(server);
Thread t = new Thread(sc);
t.start();
String msg;
/* loop reading messages from stdin and sending them to the server */
while ((msg = stdIn.readLine()) != null) {
out.println(msg);
}
}
}
class ServerConn implements Runnable {
private BufferedReader in = null;
public ServerConn(Socket server) throws IOException {
/* obtain an input stream from the server */
in = new BufferedReader(new InputStreamReader(
server.getInputStream()));
}
public void run() {
String msg;
try {
/* loop reading messages from the server and show them
* on stdout */
while ((msg = in.readLine()) != null) {
System.out.println(msg);
}
} catch (IOException e) {
System.err.println(e);
}
}
}
and here's the ChatServer.java:
/* ChatServer.java */
import java.net.ServerSocket;
import java.net.Socket;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Hashtable;
public class ChatServer {
private static int port = 5000; /* port to listen on */
public static void main (String[] args) throws IOException
{
ServerSocket server = null;
try {
server = new ServerSocket(port); /* start listening on the port */
} catch (IOException e) {
System.err.println("Could not listen on port: " + port);
System.err.println(e);
System.exit(1);
}
Socket client = null;
while(true) {
try {
client = server.accept();
} catch (IOException e) {
System.err.println("Accept failed.");
System.err.println(e);
System.exit(1);
}
/* start a new thread to handle this client */
Thread t = new Thread(new ClientConn(client));
t.start();
}
}
}
class ChatServerProtocol {
private String nick;
private ClientConn conn;
/* a hash table from user nicks to the corresponding connections */
private static Hashtable<String, ClientConn> nicks =
new Hashtable<String, ClientConn>();
private static final String msg_OK = "OK";
private static final String msg_NICK_IN_USE = "NICK IN USE";
private static final String msg_SPECIFY_NICK = "SPECIFY NICK";
private static final String msg_INVALID = "INVALID COMMAND";
private static final String msg_SEND_FAILED = "FAILED TO SEND";
/**
* Adds a nick to the hash table
* returns false if the nick is already in the table, true otherwise
*/
private static boolean add_nick(String nick, ClientConn c) {
if (nicks.containsKey(nick)) {
return false;
} else {
nicks.put(nick, c);
return true;
}
}
public ChatServerProtocol(ClientConn c) {
nick = null;
conn = c;
}
private void log(String msg) {
System.err.println(msg);
}
public boolean isAuthenticated() {
return ! (nick == null);
}
/**
* Implements the authentication protocol.
* This consists of checking that the message starts with the NICK command
* and that the nick following it is not already in use.
* returns:
* msg_OK if authenticated
* msg_NICK_IN_USE if the specified nick is already in use
* msg_SPECIFY_NICK if the message does not start with the NICK command
*/
private String authenticate(String msg) {
if(msg.startsWith("NICK")) {
String tryNick = msg.substring(5);
if(add_nick(tryNick, this.conn)) {
log("Nick " + tryNick + " joined.");
this.nick = tryNick;
return msg_OK;
} else {
return msg_NICK_IN_USE;
}
} else {
return msg_SPECIFY_NICK;
}
}
/**
* Send a message to another user.
* #recepient contains the recepient's nick
* #msg contains the message to send
* return true if the nick is registered in the hash, false otherwise
*/
private boolean sendMsg(String recipient, String msg) {
if (nicks.containsKey(recipient)) {
ClientConn c = nicks.get(recipient);
c.sendMsg(nick + ": " + msg);
return true;
} else {
return false;
}
}
/**
* Process a message coming from the client
*/
public String process(String msg) {
if (!isAuthenticated())
return authenticate(msg);
String[] msg_parts = msg.split(" ", 3);
String msg_type = msg_parts[0];
if(msg_type.equals("MSG")) {
if(msg_parts.length < 3) return msg_INVALID;
if(sendMsg(msg_parts[1], msg_parts[2])) return msg_OK;
else return msg_SEND_FAILED;
} else {
return msg_INVALID;
}
}
}
class ClientConn implements Runnable {
private Socket client;
private BufferedReader in = null;
private PrintWriter out = null;
ClientConn(Socket client) {
this.client = client;
try {
/* obtain an input stream to this client ... */
in = new BufferedReader(new InputStreamReader(
client.getInputStream()));
/* ... and an output stream to the same client */
out = new PrintWriter(client.getOutputStream(), true);
} catch (IOException e) {
System.err.println(e);
return;
}
}
public void run() {
String msg, response;
ChatServerProtocol protocol = new ChatServerProtocol(this);
try {
/* loop reading lines from the client which are processed
* according to our protocol and the resulting response is
* sent back to the client */
while ((msg = in.readLine()) != null) {
response = protocol.process(msg);
out.println("SERVER: " + response);
}
} catch (IOException e) {
System.err.println(e);
}
}
public void sendMsg(String msg) {
out.println(msg);
}
}
Now, what should I do in order to run this two files from two computers given that I have the physical connection(TCP/IP) setup already??
Thanks in advance... :)
Sounds like it's quite possibly a firewall problem. Have you tried opening a hole in your firewall for port 1001?
Have you also looked at your java.policy and make sure that it is configured to allow local codebase to open sockets?
as mentioned in comment, you should not use port < 1025 for you applications, since they are always used in deamon processes. However you should test your program like this
1) if you get connection refused then you should check the exception properly, whether client program takes time before generating exception ( that mean request is going to server and then it's giving connection refused), in that case you should try java.policy put following in a file named java.policy
grant {
permission java.net.SocketPermission ":1024-65535",
"connect,accept";
permission java.net.SocketPermission ":80", "connect";
permission java.io.FilePermission "", "read,write,delete";
permission java.security.SecurityPermission "";
};
while compiling use this flag -Djava.security.policy=java.policy
more-over you should also try -Djava.rmi.server.hostname=IP, where IP is clien-ip for client.java and server-ip for server.java
2) if you are immediately getting exception at client side then your request is not going outside your pc, so client has some problem.
check the exception properly and post them over here.
3) though i've not got access denied error, but it seems to have port problem that might be solved using policy or port>1024.
post what are you getting now.

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