Develop Reference

java: how to open exist zip file and store bufferedimage into it

I am doing a project dealing with images.
And one function is to zip images. Just as my code shows, it will new a zipOutputStream every time i call compress. As a result, the previous zip file will be overwrite if the path is the same.
public void compress() throws IOException {
String localPath = iProcessor.getPath();
String name = getName(localPath);
String type = getType(name);
ByteArrayOutputStream os = new ByteArrayOutputStream();
ImageIO.write(iProcessor.getImg(), type, os);
ByteArrayInputStream file = new ByteArrayInputStream(os.toByteArray());
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(path));
out.putNextEntry(new ZipEntry(name));
//write into zip
int len;
byte[] buffer = new byte[1024];
while ((len = file.read(buffer)) > 0) {
out.write(buffer, 0, len);
}
out.closeEntry();
file.close();
out.close();
System.out.println("Create zip file successfully!\n");
}
Is there any methods that when I input the same path, it will open the same zipfile and store the image into it? Thanks

With JDK13 and above, a zip filesystem provides an easy way to modify ZIP files. Once ZIP filesystem is setup you can create directories and copy files using the Files.createDirectories() and Files.copy():
private static void addToZip(Path zip, Path file, String zipPath) throws IOException {
try (FileSystem fs = FileSystems.newFileSystem(zip, Map.of("create","true"))) {
Path root = fs.getRootDirectories().iterator().next();
Path target = root.resolve(zipPath);
Files.createDirectories(target.getParent());
Files.copy(file, target, StandardCopyOption.REPLACE_EXISTING);
}
}
For example these calls will update / create ZIP by copying a file to particular path:
addToZip(Path.of("/tmp/xyz.zip"), Path.of("/tmp/123.txt"), "some/path/somename.txt");
addToZip(Path.of("/tmp/xyz.zip"), Path.of("/tmp/123.txt"), "anothername.txt");

Getting strange structure file when zipping a directory using Java

I wanted to zip a directory with files and subdirectories in it. I did this and worked fine but I am getting and unusual and curious file structure (At least I see it that way).
This is the created file: When I click on it, I see an "empty" directory like this: but when I unzip this I see this file structure (Not all the names are exacly as they are showed in the image below):
|mantenimiento
|Carpeta_A
|File1.txt
|File2.txt
|Carpeta_B
|Sub_carpetaB
|SubfileB.txt
|Subfile1B.txt
|Subfile2B.txt
|File12.txt
My problem somehow is that the folder "mantenimiento" is where I am zippping from (the directory which I want to zip) and I dont want it to be there, so when I unzip the just created .zip file I want it with this file structure (which are the files and directories inside "mantenimiento" directory): and the other thing is when I click on the .zip file I want to see the files and directories just like the image showed above.
I dont know what's wrong with my code, I have searched but haven't found a reference to what my problem might be.
Here's my code:
private void zipFiles( List<File> files, String directory) throws IOException
{
ZipOutputStream zos = null;
ZipEntry zipEntry = null;
FileInputStream fin = null;
FileOutputStream fos = null;
BufferedInputStream in = null;
String zipFileName = getZipFileName();
try
{
fos = new FileOutputStream( File.separatorChar + zipFileName + EXTENSION );
zos = new ZipOutputStream(fos);
byte[] buf = new byte[1024];
int len;
for(File file : files)
{
zipEntry = new ZipEntry(file.toString());
fin = new FileInputStream(file);
in = new BufferedInputStream(fin);
zos.putNextEntry(zipEntry);
while ((len = in.read(buf)) >= 0)
{
zos.write(buf, 0, len);
}
}
}
catch(Exception e)
{
System.err.println("No fue posible zipear los archivos");
e.printStackTrace();
}
finally
{
in.close();
zos.closeEntry();
zos.close();
}
}
Hope you guys can give me a hint about what I am doing wrong or what I am missing.
Thanks a lot.
Btw, the directory i am giving to the method is never used. The other parameter i am giving is a list of files which contains all the files and directories from the C:\mantenimiento directory.

I once had a problem with windows and zip files, where the created zip did not contain the entries for the folders (i.e. /, /Carpeta_A etc) only the file entries. Try adding ZipEntries for the folders without streaming content.
But as alternative to the somewhat bulky Zip API of Java you could use Filesystem (since Java7) instead. The following example is for Java8 (lambda):
//Path pathToZip = Paths.get("path/to/your/folder");
//Path zipFile = Paths.get("file.zip");
public Path zipPath(Path pathToZip, Path zipFile) {
Map<String, String> env = new HashMap<String, String>() {{
put("create", "true");
}};
try (FileSystem zipFs = FileSystems.newFileSystem(URI.create("jar:" + zipFile.toUri()), env)) {
Path root = zipFs.getPath("/");
Files.walk(pathToZip).forEach(path -> zip(root, path));
}
}
private static void zip(final Path zipRoot, final Path currentPath) {
Path entryPath = zipRoot.resolve(currentPath.toString());
try {
Files.createDirectories(entryPath.getParent());
Files.copy(currentPath, entryPath);
} catch (IOException e) {
throw new RuntimeException(e);
}
}

how to replacing some files within a certain directory inside a jar file?

I'm having the problem of replacing or updating some files within a certain directory inside a jar file.
I've read a few post already. The code (the JarUpdater Class) given at this link Updating .JAR's contents from code
is being very helpful for me to understand the role and the use of ZipInputStream, ZipOutputStream and ZipEntry, etc..
However, when I run it,
I have an EOF Exception
[EDITED by mk7: I found out the jar file was corrupted after I went through it 20 times or so. So after I replaced the jar file with a new one, the EOF Exception went away. The other two problems below still remains unsolved]
these two new xml files only get copied to the "root directory" of the jar file.
these two new xml files NEVER replaced the two original files inside a directory called /conf.
Which lines of code should I change in order to replace the xml files with the new ones?
With the System.out.println, I did see that the while loop steps through every directory and compare at every file as expected. A new temp jar was also created as expected...
I thought the statement "notInFiles = false" would take care of my need but it's NOT.
How do I step into the /conf and only replace those two files and NOT leave a copy at the root of the jar file?
What am I missing? Thanks for any insight!
Below are the code from that link.
import java.io.*;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;
public class JarUpdater {
public static void main(String[] args) {
File[] contents = {new File("abc.xml"),
new File("def.xml")};
File jarFile = new File("xyz.jar");
try {
updateZipFile(jarFile, contents);
} catch (IOException e) {
e.printStackTrace();
}
}
public static void updateZipFile(File jarFile,
File[] contents) throws IOException {
// get a temp file
File tempFile = File.createTempFile(jarFile.getName(), null);
// delete it, otherwise you cannot rename your existing zip to it.
tempFile.delete();
System.out.println("tempFile is " + tempFile);
boolean renameOk=jarFile.renameTo(tempFile);
if (!renameOk)
{
throw new RuntimeException("could not rename the file "+jarFile.getAbsolutePath()+" to "+tempFile.getAbsolutePath());
}
byte[] buf = new byte[1024];
ZipInputStream zin = new ZipInputStream(new FileInputStream(tempFile));
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(jarFile));
ZipEntry entry = zin.getNextEntry();
while (entry != null) {
String name = entry.getName();
boolean notInFiles = true;
for (File f : contents) {
System.out.println("f is " + f);
if (f.getName().equals(name)) {
// that file is already inside the jar file
notInFiles = false;
System.out.println("file already inside the jar file");
break;
}
}
if (notInFiles) {
System.out.println("name is " + name);
System.out.println("entry is " + entry);
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry(name));
// Transfer bytes from the ZIP file to the output file
int len;
while ((len = zin.read(buf)) > 0) {
out.write(buf, 0, len);
}
}
entry = zin.getNextEntry();
}
// Close the streams
zin.close();
// Compress the contents
for (int i = 0; i < contents.length; i++) {
InputStream in = new FileInputStream(contents[i]);
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry(contents[i].getName()));
// Transfer bytes from the file to the ZIP file
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
// Complete the entry
out.closeEntry();
in.close();
}
// Complete the ZIP file
out.close();
tempFile.delete();
}
}

In your first cycle (while loop) where you copy the entries which you don't want to replace you don't close the entries in the output zip file. Add out.closeEntry(); like this:
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry(name));
// Transfer bytes from the ZIP file to the output file
int len;
while ((len = zin.read(buf)) > 0) {
out.write(buf, 0, len);
}
// ADD THIS LINE:
out.closeEntry();
Also when you check if an entry is to be replaced, you should compare it to a full path, not just to the name of the file. For example if you want to replace abc.xml which is in the /conf folder, you should compare the entry name to "/conf/abc.xml" and not to "abc.xml".
To properly check if an entry is to be replaced:
String name = entry.getName();
boolean notInFiles = true;
for (File f : contents) {
System.out.println("f is " + f);
if (name.equals("/conf/" + f.getName()) {
// that file is already inside the jar file
notInFiles = false;
System.out.println("file already inside the jar file");
break;
}
}
And when you add the entries to the output which are the replaced files, you also have to specify the entry name having full path, e.g. "/conf/abc.xml" and not just "abc.xml" because it would put "abc.xml" in the root of the output zip.
To do this, start the entry name with "/conf/" like this:
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry("/conf/" + contents[i].getName()));

For URIs with the protocol jar:file: (usable for all zip files), you can use a zip file system.
URI jarUri = new URI("jar:" + jarFile.toURI().toString()); // "jar:file:/C:/../xyz.jar"
Map<String, String> zipProperties = new HashMap<>();
zipProperties.put("encoding", "UTF-8");
try (FileSystem zipFS = FileSystems.newFileSystem(jarUri, zipProperties)) {
for (File file : contents) {
Path updatePath = zipFS.getPath("/" + file.getName());
Files.delete(updatePath);
Files.copy(file.toPath(), updatePath, StandardCopyOption.REPLACE_EXISTING);
}
} // closes.
One way to derive the URI is prefixing "jar:" to a File.toURI().
This is a bit more elegant and abstract, and also allows Files.copy in and out the zip. Something to keep in ones tool chest.

Extract a .tar.gz file in java (JSP)

I can't seem to import the packages needed or find any online examples of how to extract a .tar.gz file in java.
What makes it worse is I'm using JSP pages and am having trouble importing packages into my project. I'm copying the .jar's into WebContent/WEB-INF/lib/ and then right clicking on the project and selecting import external jar and importing it. Sometimes the packages resolve, other times they don't. Can't seem to get GZIP to import either. The imports in eclipse for jsp aren't intuitive like they are in normal Java code where you can right click a recognized package and select import.
I've tried the Apache commons library, the ice and another one called JTar. Ice has imported, but I can't find any examples of how to use it?
I guess I need to uncompress the gzipped part first, then open it with the tarstream?
Any help is greatly appreciated.

The accepted answer works fine, but I think it is redundant to have a write to file operation.
You could use something like
TarArchiveInputStream tarInput =
new TarArchiveInputStream(new GZipInputStream(new FileInputStream("Your file name")));
TarArchiveEntry currentEntry = tarInput.getNextTarEntry();
while(currentEntry != null) {
File f = currentEntry.getFile();
// TODO write to file as usual
}
Hope this help.
Maven Repo

Ok, i finally figured this out, here is my code in case this helps anyone in the future.
Its written in Java, using the apache commons io and compress librarys.
File dir = new File("directory/of/.tar.gz/files/here");
File listDir[] = dir.listFiles();
if (listDir.length!=0){
for (File i:listDir){
/* Warning! this will try and extract all files in the directory
if other files exist, a for loop needs to go here to check that
the file (i) is an archive file before proceeding */
if (i.isDirectory()){
break;
}
String fileName = i.toString();
String tarFileName = fileName +".tar";
FileInputStream instream= new FileInputStream(fileName);
GZIPInputStream ginstream =new GZIPInputStream(instream);
FileOutputStream outstream = new FileOutputStream(tarFileName);
byte[] buf = new byte[1024];
int len;
while ((len = ginstream.read(buf)) > 0)
{
outstream.write(buf, 0, len);
}
ginstream.close();
outstream.close();
//There should now be tar files in the directory
//extract specific files from tar
TarArchiveInputStream myTarFile=new TarArchiveInputStream(new FileInputStream(tarFileName));
TarArchiveEntry entry = null;
int offset;
FileOutputStream outputFile=null;
//read every single entry in TAR file
while ((entry = myTarFile.getNextTarEntry()) != null) {
//the following two lines remove the .tar.gz extension for the folder name
String fileName = i.getName().substring(0, i.getName().lastIndexOf('.'));
fileName = fileName.substring(0, fileName.lastIndexOf('.'));
File outputDir = new File(i.getParent() + "/" + fileName + "/" + entry.getName());
if(! outputDir.getParentFile().exists()){
outputDir.getParentFile().mkdirs();
}
//if the entry in the tar is a directory, it needs to be created, only files can be extracted
if(entry.isDirectory){
outputDir.mkdirs();
}else{
byte[] content = new byte[(int) entry.getSize()];
offset=0;
myTarFile.read(content, offset, content.length - offset);
outputFile=new FileOutputStream(outputDir);
IOUtils.write(content,outputFile);
outputFile.close();
}
}
//close and delete the tar files, leaving the original .tar.gz and the extracted folders
myTarFile.close();
File tarFile = new File(tarFileName);
tarFile.delete();
}
}

How can I add entries to an existing zip file in Java? [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Appending files to a zip file with Java
Opening the file with a ZipOutputStream overwrites it. Is there a way to keep the file and just add new entries?

The function renames the existing zip file to a temporary file and then adds all entries in the existing zip along with the new files, excluding the zip entries that have the same name as one of the new files.
public static void addFilesToExistingZip(File zipFile,
File[] files) throws IOException {
// get a temp file
File tempFile = File.createTempFile(zipFile.getName(), null);
// delete it, otherwise you cannot rename your existing zip to it.
tempFile.delete();
boolean renameOk=zipFile.renameTo(tempFile);
if (!renameOk)
{
throw new RuntimeException("could not rename the file "+zipFile.getAbsolutePath()+" to "+tempFile.getAbsolutePath());
}
byte[] buf = new byte[1024];
ZipInputStream zin = new ZipInputStream(new FileInputStream(tempFile));
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFile));
ZipEntry entry = zin.getNextEntry();
while (entry != null) {
String name = entry.getName();
boolean notInFiles = true;
for (File f : files) {
if (f.getName().equals(name)) {
notInFiles = false;
break;
}
}
if (notInFiles) {
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry(name));
// Transfer bytes from the ZIP file to the output file
int len;
while ((len = zin.read(buf)) > 0) {
out.write(buf, 0, len);
}
}
entry = zin.getNextEntry();
}
// Close the streams
zin.close();
// Compress the files
for (int i = 0; i < files.length; i++) {
InputStream in = new FileInputStream(files[i]);
// Add ZIP entry to output stream.
out.putNextEntry(new ZipEntry(files[i].getName()));
// Transfer bytes from the file to the ZIP file
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
// Complete the entry
out.closeEntry();
in.close();
}
// Complete the ZIP file
out.close();
tempFile.delete();
}

You could use zipFile.entries() to get an enumeration of all of the ZipEntry objects in the existing file, loop through them and add them all to the ZipOutputStream, and then add your new entries in addition.

You have to be sure to add a CRC32 for uncompressed files added to a zip. Check out the example here.
http://jcsnippets.atspace.com/java/input-output/create-zip-file.html
You can do it in a simple way, without rewriting everything, with Zip4j.
Here it shows:
http://blog.michalszalkowski.com/java/zip4j-add-file-to-existing-zip-file/
And you can do it using Zip4J's ZipOutputStream too, using SplitOutputStream together.
<dependency>
<groupId>net.lingala.zip4j</groupId>
<artifactId>zip4j</artifactId>
<version>1.3.1</version>
</dependency>
ex:
ZipFile zipFile = new ZipFile(new File("/home/szalek/zip/core1.zip"));
ArrayList filesToAdd = new ArrayList();
filesToAdd.add(new File("/home/szalek/zip/someData.txt"));
ZipParameters parameters = new ZipParameters();
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE);
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
//password
parameters.setEncryptFiles(true);
parameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_STANDARD);
parameters.setPassword("test123!");
//password
zipFile.addFiles(filesToAdd, parameters);