Develop Reference

How to restore file from GDrive?

I am making an app which stores its SQLite Database backup on GDrive. I succeeded in signing in and uploading the file in the drive but failed to restore it. Following is the code.
I use SQLiteDatabase to store the fileID so that when it is required while updating and restoring, it can be used. I am looking for a method which will make use of FileID to restore.
Error occurs at file.getDownloadUrl() and file.getContent().
class DriveClassHelper
{
private final Executor mExecutor = Executors.newSingleThreadExecutor();
private static Drive mDriveService;
private String FileID = null;
private static String filePath = "/data/data/com.example.gdrivebackup/databases/Data.db";
DriveClassHelper(Drive mDriveService)
{
DriveClassHelper.mDriveService = mDriveService;
}
// ---------------------------------- TO BackUp on Drive -------------------------------------------
public Task<String> createFile()
{
return Tasks.call(mExecutor, () ->
{
File fileMetaData = new File();
fileMetaData.setName("Backup");
java.io.File file = new java.io.File(filePath);
String mimeType = MimeTypeMap.getSingleton().getExtensionFromMimeType("application/x-sqlite-3");
FileContent mediaContent = new FileContent(mimeType, file);
File myFile = null;
FileID = getFileIDFromDatabase();
try {
if (FileID != null) {
Log.i("CALLED : ", FileID);
//mDriveService.files().delete().execute();
myFile = mDriveService.files().update(FileID, fileMetaData, mediaContent).execute();
} else {
myFile = mDriveService.files().create(fileMetaData, mediaContent).execute();
MainActivity.demoSQLite.insertData(myFile.getId());
}
} catch (Exception e) {
e.printStackTrace();
}
if (myFile == null) {
throw new IOException("Null Result when requesting file creation");
}
Log.i("ID:", myFile.getId());
return myFile.getId();
}
);
}
// -------------------------------------------------------------------------------------------------
// ---------------------------------- TO get File ID -------------------------------------------
private static String getFileIDFromDatabase()
{
String FileIDFromMethod = null;
Cursor result = MainActivity.demoSQLite.getData();
if (result.getCount() == 0) {
Log.i("CURSOR :", "NO ENTRY");
return null;
} else {
while (result.moveToNext()) {
FileIDFromMethod = result.getString(0);
}
return FileIDFromMethod;
}
}
// -------------------------------------------------------------------------------------------------
// ---------------------------------- TO Restore -------------------------------------------
public static class Restore extends AsyncTask<Void, Void, String>
{
#Override
protected String doInBackground(Void... params) {
String fileId = null;
try
{
fileId = getFileIDFromDatabase();
if (fileId != null)
{
File file = mDriveService.files().get(fileId).execute();
downloadFile(file);
}
else
{
return null;
}
}
catch (Exception e)
{
e.printStackTrace();
}
return fileId;
}
private void downloadFile(File file)
{
InputStream mInput = null;
FileOutputStream mOutput = null;
if (file.getDownloadUrl() != null && file.getDownloadUrl().length() > 0) //Error occurs at file.getDownloadUrl()
{
try
{
HttpResponse resp = mDriveService.getRequestFactory().buildGetRequest(new GenericUrl(file.getDownloadUrl())).execute();
mInput = resp.getContent();
String outFileName = "file://" + Environment.getDataDirectory().getPath() + filePath;
// Log.e("com.example.myapp", "getDatabasePath="+ getDatabasePath(""));
//Log.e("com.example.myapp", "outFileName="+outFileName);
// String outFileName = "../databases/" + "Quickpay.db";
mOutput = new FileOutputStream(outFileName);
byte[] mBuffer = new byte[1024];
int mLength;
while ((mLength = mInput.read(mBuffer)) > 0)
{
mOutput.write(mBuffer, 0, mLength);
}
mOutput.flush();
}
catch (IOException e)
{
// An error occurred.
e.printStackTrace();
// return null;
}
finally
{
try
{
//Close the streams
if (mOutput != null)
{
mOutput.close();
}
if (mInput != null)
{
mInput.close();
}
}
catch (IOException e)
{
Log.e("com.example.myapp", "failed to close databases");
}
}
}
else
{
// The file doesn't have any content stored on Drive.
// return null;
Log.e("com.example.myapp", "No content on Drive");
}
}
}
}
The Gradle file is like
implementation 'com.google.android.gms:play-services-auth:16.0.1'
implementation('com.google.apis:google-api-services-drive:v3-rev136-1.25.0')
{
exclude group: 'org.apache.httpcomponents'
}
implementation('com.google.api-client:google-api-client-android:1.26.0')
{
exclude group: 'org.apache.httpcomponents'
}
implementation 'com.google.http-client:google-http-client-gson:1.26.0'

As far as i know Download URL is only avalibale in Google drive api v2 and not in V3.
Short lived download URL for the file. This field is only populated for files with content stored in Google Drive; it is not populated for Google Docs or shortcut files.
It was not very stable in my opinion as not all file types would return a download url.
Using Google Drive v3 you should download the file using a stream.
String fileId = "0BwwA4oUTeiV1UVNwOHItT0xfa2M";
OutputStream outputStream = new ByteArrayOutputStream();
driveService.files().get(fileId)
.executeMediaAndDownloadTo(outputStream);
This should work with the restore. Let me know if it doesnt and i will have a look its been a while since i have tried restore.

How to download a file into the specific folder in java?

I am working on an application which will download 3rd party dependencies to a particular folder and then execute dependency check on it. The files downloaded can be of any type, they can be zip, jar or may b a folder. I am trying to find a code example but nothing seems to work for me. I tried NIO in java but that seems to work only for writing to a particular file not folder. Below is code where I used NIO
// Checking If The File Exists At The Specified Location Or Not
Path filePathObj = Paths.get(filePath);
boolean fileExists = Files.exists(filePathObj);
if(fileExists) {
try {
urlObj = new URL(sampleUrl);
rbcObj = Channels.newChannel(urlObj.openStream());
fOutStream = new FileOutputStream(filePath);
fOutStream.getChannel().transferFrom(rbcObj, 0, Long.MAX_VALUE);
System.out.println("! File Successfully Downloaded From The Url !");
} catch (IOException ioExObj) {
System.out.println("Problem Occured While Downloading The File= " + ioExObj.getMessage());
} finally {
try {
if(fOutStream != null){
fOutStream.close();
}
if(rbcObj != null) {
rbcObj.close();
}
} catch (IOException ioExObj) {
System.out.println("Problem Occured While Closing The Object= " + ioExObj.getMessage());
}
}
} else {
System.out.println("File Not Present! Please Check!");
}```

public Class CopyAndWrite {
public static final String SOURCES = "C:\\Users\\Administrator\\Desktop\\resources";
public static final String TARGET = "C:\\Users\\Administrator\\Desktop\\111";
public static void main (String[]args) throws IOException {
Path startingDir = Paths.get(SOURCES);
Files.walkFileTree(startingDir, new FindJavaVisitor());
}
private static class FindJavaVisitor extends SimpleFileVisitor<Path> {
#Override
public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) throws IOException {
if (!StringUtils.equals(dir.toString(), SOURCES)) {
Path targetPath = Paths.get(TARGET + dir.toString().substring(SOURCES.length()));
if (!Files.exists(targetPath)) {
Files.createDirectory(targetPath);
}
}
return FileVisitResult.CONTINUE;
}
#Override
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
Path targetPath = Paths.get(TARGET + file.toString().substring(SOURCES.length()));
copyFile(targetPath, Files.readAllBytes(file));
return FileVisitResult.CONTINUE;
}
}
private static void copyFile (Path path,byte[] bytes){
// write file
try {
Files.write(path, bytes);
} catch (IOException e) {
e.printStackTrace();
}
}
}

Using OKHttpClient to download the file and place in a folder.
Request request = new Request.Builder().url(downloadUrl).build();
Response response;
try {
response = client.newCall(request).execute();
if (response.isSuccessful()) {
fileName = abc.zip
Path targetPath = new File(inDir + File.separator + fileName).toPath();
try (FileOutputStream fos = new FileOutputStream(targetPath)) {
fos.write(response.body().bytes());
}
return 0;
}
} catch (IOException e) {
logger.error(e.getMessage());
}```

File Not Found Exception : Open failed:ENOENT

I am new for android, Im downloading image from URL and set in listView. Its working some mobile and not creating file/directory in some mobile.
Its throw error like:
java.io.FileNotFoundException: /storage/emulated/0/.tam/veg.png: open failed: ENOENT (No such file or directory)
I don't know why its throw error like this some mobile. I want to create directory all type of mobile. Please anyone help me.
Here my code:
public class ImageStorage {
public static String saveToSdCard(Bitmap bitmap, String filename) {
String stored = null;
File sdcard = Environment.getExternalStorageDirectory();
File folder = new File(sdcard.getAbsoluteFile(), ".tam");//the dot makes this directory hidden to the user
folder.mkdir();
File file = new File(folder.getAbsoluteFile(), filename) ;
if (file.exists())
return stored ;
try {
FileOutputStream out = new FileOutputStream(file);
bitmap.compress(Bitmap.CompressFormat.PNG, 90, out);
out.flush();
out.close();
stored = "success";
} catch (Exception e) {
e.printStackTrace();
}
return stored;
}
public static File getImage(String imagename) {
File mediaImage = null;
try {
String root = Environment.getExternalStorageDirectory().getAbsolutePath();
File myDir = new File(root);
if (!myDir.exists())
return null;
mediaImage = new File(myDir.getPath() + "/.tam/"+imagename);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return mediaImage;
}
public static File checkifImageExists(String imagename) {
File file = ImageStorage.getImage("/" + imagename);
if (file.exists()) {
return file;
} else {
return null;
}
}
public static String getImageName(String value){
String getName[] = value.split("/");
return getName[4];
}
}
Below path not in all mobile:
/storage/emulated/0/
Thanks in advance!!

Maybe u should check if there's external storage in the mobile before u use this path
public String getDir(Context context) {
String checkPath = null;
if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())
|| !Environment.isExternalStorageRemovable()) {
checkPath = Environment.getExternalStorageDirectory().getPath();
} else {
checkPath = context.getCacheDir().getPath();
}
return checkPath;
}

Java: Iterate over HTML files in a directory

I'm taking HTML file and one XSLT file as input and generating HTML output but in my folder there are multiple HTML files and I've to take each of them as input and generate the corresponding output file while XSLT input file remains same every time. Currently in my code I'm repeating the code block every time to take the input HTML file. Instead of this I want to iterate over all the HTML files in the folder and take them as input file one by one to generate the output. In my current code file names are also fixed like part_1.html but it can vary and in that case this code won't work and this will create problem. Can anyone please help out in this matter:
Thanking you!
Current Java code (Sample for two files):
public void tranformation() {
// TODO Auto-generated method stub
transform1();
transform2();
}
public static void transform1(){
String inXML = "C:/SCORM_CP/part_1.html";
String inXSL = "C:/source/xslt/html_new.xsl";
String outTXT = "C:/SCORM_CP/part1_copy_copy.html";
String renamedFile = "C:/SCORM_CP/part_1.html";
File oldfile =new File(outTXT);
File newfile =new File(renamedFile);
HTML_Convert hc = new HTML_Convert();
try {
hc.transform(inXML,inXSL,outTXT);
} catch(TransformerConfigurationException e) {
System.err.println("Invalid factory configuration");
System.err.println(e);
} catch(TransformerException e) {
System.err.println("Error during transformation");
System.err.println(e);
}
try{
File file = new File(inXML);
if(file.delete()){
System.out.println(file.getName() + " is deleted!");
}else{
System.out.println("Delete operation is failed.");
}
}catch(Exception e){
e.printStackTrace();
}
if(oldfile.renameTo(newfile)){
System.out.println("Rename succesful");
}else{
System.out.println("Rename failed");
}
}
public static void transform2(){
String inXML = "C:/SCORM_CP/part_2.html";
String inXSL = "C:/source/xslt/html_new.xsl";
String outTXT = "C:/SCORM_CP/part2_copy_copy.html";
String renamedFile = "C:/SCORM_CP/part_2.html";
File oldfile =new File(outTXT);
File newfile =new File(renamedFile);
HTML_Convert hc = new HTML_Convert();
try {
hc.transform(inXML,inXSL,outTXT);
} catch(TransformerConfigurationException e) {
System.err.println("Invalid factory configuration");
System.err.println(e);
} catch(TransformerException e) {
System.err.println("Error during transformation");
System.err.println(e);
}
try{
File file = new File(inXML);
if(file.delete()){
System.out.println(file.getName() + " is deleted!");
}else{
System.out.println("Delete operation is failed.");
}
}catch(Exception e){
e.printStackTrace();
}
if(oldfile.renameTo(newfile)){
System.out.println("Rename succesful");
}else{
System.out.println("Rename failed");
}
}
public void transform(String inXML,String inXSL,String outTXT)
throws TransformerConfigurationException,
TransformerException {
TransformerFactory factory = TransformerFactory.newInstance();
StreamSource xslStream = new StreamSource(inXSL);
Transformer transformer = factory.newTransformer(xslStream);
transformer.setErrorListener(new MyErrorListener());
StreamSource in = new StreamSource(inXML);
StreamResult out = new StreamResult(outTXT);
transformer.transform(in,out);
System.out.println("The generated XML file is:" + outTXT);
}
}

File dir = new File("/path/to/dir");
File[] htmlFiles = dir.listFiles(new FilenameFilter() {
#Override
public boolean accept(File dir, String name) {
return name.endsWith(".html");
}
});
if (htmlFiles != null) for (File html: htmlFiles) {
...
}

You have to implement something like
public class Transformation {
public static void main (String[] args){
transformation(".", ".");
}
public static void transform(String inXML, String inXSL, String outTXT, String renamedFile){
System.out.println(inXML);
System.out.println(inXSL);
System.out.println(outTXT);
System.out.println(renamedFile);
}
public static void transformation(String inFolder, String outFolder){
File infolder = new File(inFolder);
File outfolder = new File(outFolder);
if (infolder.isDirectory() && outfolder.isDirectory()){
System.out.println("In " + infolder.getAbsolutePath());
System.out.println("Out " + outfolder.getAbsolutePath());
File[] listOfFiles = infolder.listFiles();
String outPath = outfolder.getAbsolutePath();
String inPath = infolder.getAbsolutePath();
for (File f: listOfFiles) {
if (f.isFile() ) {
System.out.println("File " + f.getName());
int indDot = f.getName().lastIndexOf(".");
String name = f.getName().substring(0, indDot);
String ext = f.getName().substring(indDot+1);
if (ext != null && ext.equals("html")){
transform(f.getAbsolutePath(), inPath+File.separator+name+".xsl", outPath+File.separator+name+".txt", outPath+File.separator+name+".html");
}
}
}
}
}
}

First you should write a method that take inXML, inXSL, outTXT and renamedFile as arguments.
Then, using the list() method of the File class, that eventually take a FilenameFilter, you may iterate over the files you want to transform.
Here is a sample of FilenameFilter :
FilenameFilter filter = new FilenameFilter() {
public boolean accept(File dir, String name) {
return name.contains("part");
}
};
Regards

use DirectoryScanner which will make your job easier
Example of usage:
String[] includes = {"**\*.html"};
ds.setIncludes(includes);
ds.setBasedir(new File("test"));
ds.setCaseSensitive(true);
ds.scan();
System.out.println("FILES:");
String[] files = ds.getIncludedFiles();
for (int i = 0; i < files.length; i++) {
System.out.println(files[i]);
}
http://plexus.codehaus.org/plexus-utils/apidocs/org/codehaus/plexus/util/DirectoryScanner.html

Trying to check if a file exists in internal storage

The following code is how I am trying to identify if a file exists in the internal storage, MODE_PRIVATE.
public boolean isset(String filename){
FileInputStream fos = null;
try {
fos = openFileInput(filename);
//fos = openFileInput(getFilesDir()+"/"+filename);
if (fos != null) {
return true;
}else{
return false;
}
} catch (FileNotFoundException e) {
return false;
}
//File file=new File(mContext.getFilesDir(),filename);
//boolean exists = fos.exists();
}
However, it goes into the exception and doesn't continue with the code. It doesn't do the return. Why?

hope this method helps you.
public boolean fileExist(String fname){
File file = getBaseContext().getFileStreamPath(fname);
return file.exists();
}

For internal storage, this works for me:
public boolean isFilePresent(String fileName) {
String path = getContext().getFilesDir().getAbsolutePath() + "/" + fileName;
File file = new File(path);
return file.exists();
}

Kotlin: This works for me !!
fun check(path: String?): Boolean
{
val file = File(path)
return file.exists()
}