Android file storage - java

I have a zip file in assets. On first run of app, zip file (all files and folders) gets unzipped and stored in internal storage area. The base unzipped path is getFilesDir(). Since zip also contains folders, i could not use openFileOutput as it gave an error, contains a path separator. So i have used FileOutputStream instead which is now working fine. Since FileOutputStream does not expect private flag. Are these unzipped files and folders are private to my app or can they be accessed from other apps?
Here's the code,
`public boolean unpackZip(InputStream is, String path) throws IOException {
String filename;
ZipInputStream zis = new ZipInputStream(new BufferedInputStream(is));
ZipEntry ze;
byte[] buffer = new byte[1024];
int count;
while ((ze = zis.getNextEntry()) != null) {
filename = ze.getName();
// Need to create directories if not exists, or
// it will generate an Exception...
if (ze.isDirectory()) {
File fmd = new File(path + filename);
fmd.mkdirs();
continue;
}
FileOutputStream fout = new FileOutputStream(path + filename);
while ((count = zis.read(buffer)) != -1) {
fout.write(buffer, 0, count);
}
fout.close();
zis.closeEntry();
}
zis.close();
return true;
}`

Related

How to read XML from Zip without extracting the zip in the directory

I want to unzip and read the xml file data without actually unzipping or extracting the zip file in my project folder. How can I do this.
I have written code to unzip a file and make directory but I don't know how to do it without actually extracting.
My code -
public class ZipFile {
public static void main(String[] args) throws IOException {
String zipFileName = "people.zip";
String destDirectory = "src/main/xmlfiles";
File destDirectoryFolder = new File(destDirectory);
if(!destDirectoryFolder.exists()){
destDirectoryFolder.mkdir();
}
byte[] buffer = new byte[1024];
ZipInputStream zis = new ZipInputStream(new FileInputStream(zipFileName));
ZipEntry zipEntry = zis.getNextEntry();
while (zipEntry != null){
String filePath = destDirectory + File.separator + zipEntry.getName();
System.out.println("unzipping "+ filePath);
if(!zipEntry.isDirectory()){
FileOutputStream fos = new FileOutputStream(filePath);
int len ;
while((len = zis.read(buffer)) > 0){
fos.write(buffer, 0 ,len);
}
fos.close();
}
else{
File dir = new File(filePath);
dir.mkdir();
}
zis.closeEntry();
zipEntry = zis.getNextEntry();
}
zis.closeEntry();
zis.close();
System.out.println("Unzip complete");
}
}
I also want to read the xml file, without parser I just want to read it like normal xml file. Anyone can please give me any idea how to do it what should I need to learn! Thanks

getting error while unzipping

My UnZip class does not unzip whole the file. This class is called from another activity. My zip file is saved in the main directory of the phone's internal storage. The zip file has folders and some video.
What's wrong with this unzip?
What and how should I read file from zip' decompress and unzip is the same meaning?
Thanks for your help!
public class Unzip {
private static final String INPUT_ZIP_FILE = "sdcard/downloaded_issue.zip";
private static final String OUTPUT_FOLDER = "sdcard/Atlantis/";
public static void main()
{
Unzip unZip = new Unzip();
unZip.unZipIt(INPUT_ZIP_FILE, OUTPUT_FOLDER);
}
/**
* Unzip it
* #param zipFile input zip file
* #param outputFolder zip file output folder
*/
public void unZipIt(String zipFile, String outputFolder){
byte[] buffer = new byte[1024];
try{
//create output directory is not exists
File folder = new File(OUTPUT_FOLDER);
if(!folder.exists()){
folder.mkdir();
}
//get the zip file content
ZipInputStream zis =
new ZipInputStream(new FileInputStream(zipFile));
//get the zipped file list entry
ZipEntry ze = zis.getNextEntry();
while(ze!=null){
String fileName = ze.getName();
File newFile = new File(outputFolder + File.separator + fileName);
System.out.println("file unzip : "+ newFile.getAbsoluteFile());
//create all non exists folders
//else you will hit FileNotFoundException for compressed folder
new File(newFile.getParent()).mkdirs();
FileOutputStream fos = new FileOutputStream(newFile);
int len;
while ((len = zis.read(buffer)) > 0) {
fos.write(buffer, 0, len);
}
fos.close();
if (ze.isDirectory()) {
ze = zis.getNextEntry();
}
}
zis.closeEntry();
zis.close();
System.out.println("Done");
}catch(IOException ex){
ex.printStackTrace();
}
}
}
I think your 'while' loop is broken; you're only fetching the next entry if that next entry is a directory, while I assume you're probably trying to skip the directories.
Anyway, since you create the folders for all files you encounter, you can just skip the folder entries and write the file entries. The only exception would be the creation of empty folders.
Replacing the while-loop by this code should work:
while(ze!=null){
String fileName = ze.getName();
File newFile = new File(outputFolder + File.separator + fileName);
System.out.println("file unzip : "+ newFile.getAbsoluteFile());
//create all non exists folders
//else you will hit FileNotFoundException for compressed folder
if (ze.isDirectory()) {
// create the folder
newFile.mkdirs();
}
else {
// create the parent folder and write to disk
new File(newFile.getParent()).mkdirs();
FileOutputStream fos = new FileOutputStream(newFile);
int len;
while ((len = zis.read(buffer)) > 0) {
fos.write(buffer, 0, len);
}
fos.close();
}
// get the next item
ze = zis.getNextEntry();
}

Java - Getting specific folder and files from zip file

So I am working on an Android app and what I am trying to do is make it so a user selects a zip file, it extracts the contents of it into an apk and installs the modified APK for the user. Right now all the files in the zip file have to be in the root of the zip file for it to work, if there is a directory and than the files I need it will not work. I am trying to make it scan for, for example the 'assets' folder and than get the directory its located in and copy all the files from that directory. I've tried extracting the files first and scanning using a loop, and for some reason had no success doing that, and it was time consuming anyways. If you know any libraries or could point me in the right direction that would be great! Thanks!
BTW you can extract all the files from zip folder like below. i.e
private String unpackZip(String path, String zipname) {
String apkfilename = "";
InputStream is;
ZipInputStream zis;
try {
String filename;
is = new FileInputStream(path + "/" + zipname);
zis = new ZipInputStream(new BufferedInputStream(is));
ZipEntry ze;
byte[] buffer = new byte[1024];
int count;
while ((ze = zis.getNextEntry()) != null) {
filename = ze.getName();
// Need to create directories if not exists, or
// it will generate an Exception...
if (ze.isDirectory()) {
File fmd = new File(path + "/" + filename);
fmd.mkdirs();
continue;
}
// This condition is to only extract the apk file
if (filename.endsWith(".apk")) {
apkfilename = filename;
FileOutputStream fout = new FileOutputStream(path + "/"
+ filename);
while ((count = zis.read(buffer)) != -1) {
fout.write(buffer, 0, count);
}
fout.close();
zis.closeEntry();
}
}
zis.close();
} catch (IOException e) {
e.printStackTrace();
return apkfilename;
}
return apkfilename;
}
//To install the apk file call the method
String apkfilename=unpackZip(Environment.getExternalStorageDirectory()
.getPath(), "temp.zip");
try {
File file = new File(Environment.getExternalStorageDirectory()
.getPath(), apkfilename);
Intent promptInstall = new Intent(Intent.ACTION_VIEW).setDataAndType(
Uri.fromFile(file), "application/vnd.android.package-archive");
startActivity(promptInstall);
} catch (Exception e) {
e.printStackTrace();
}
//Also add the read write permission
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

How to unzip a Zip file which contains Images without dropping any image in android? [closed]

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Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 8 years ago.
Improve this question
I am working on unzip the zip file which contains Images only here below my code is given.
public void unZipImages(String zipFile, String outputFolder) {
byte[] buffer = new byte[2048];
try {
// create output directory is not exists
File folder = new File(Environment.getExternalStorageDirectory()
+ "/final_unzip_data/" + AppConstants.ManufacturerCode
+ "/Catalog/" + ""); if (!folder.exists()) {
folder.mkdir(); }
// get the zip file content
ZipInputStream zis = new ZipInputStream(
new FileInputStream(zipFile)); // get the zipped file list entry ZipEntry ze = zis.getNextEntry();
while (ze != null) {
String fileName = ze.getName();
if (fileName.contains("\\")) {
fileName = fileName.replace("\\", "/");
}
File newFile = new File(outputFolder + File.separator
+ fileName);
System.out.println("file unzip : " + newFile.getAbsoluteFile());
new File(newFile.getParent()).mkdirs();
FileOutputStream fos = new FileOutputStream(newFile);
int len;
while ((len = zis.read(buffer)) > 0) {
fos.write(buffer, 0, len);
}
fos.close();
ze = zis.getNextEntry(); }
zis.closeEntry(); zis.close();
System.out.println("Done");
} catch (IOException ex) { ex.printStackTrace(); } }
But I don't know what the error is occurring to unzip the file some images are dropping. I have searched many types of codes for unzip but nothing worked.
This code has solved my problem
private void unzipImage(String zipFile, String extractFolder) {
try {
CreateDir();
int BUFFER = 4096;
File file = new File(zipFile);
ZipFile zip = new ZipFile(file);
String newPath = extractFolder;
new File(newPath).mkdir();
Enumeration zipFileEntries = zip.entries();
// Process each entry
while (zipFileEntries.hasMoreElements()) {
// grab a zip file entry
ZipEntry entry = (ZipEntry) zipFileEntries.nextElement();
String currentEntry = entry.getName();
currentEntry = currentEntry.replace('\\', '/');
File destFile = new File(newPath, currentEntry);
// destFile = new File(newPath, destFile.getName());
File destinationParent = destFile.getParentFile();
// create the parent directory structure if needed
destinationParent.mkdirs();
if (!entry.isDirectory()) {
BufferedInputStream is = new BufferedInputStream(
zip.getInputStream(entry));
int currentByte;
// establish buffer for writing file
byte data[] = new byte[BUFFER];
// write the current file to disk
FileOutputStream fos = new FileOutputStream(destFile);
BufferedOutputStream dest = new BufferedOutputStream(fos,
BUFFER);
// read and write until last byte is encountered
while ((currentByte = is.read(data, 0, BUFFER)) != -1) {
dest.write(data, 0, currentByte);
}
dest.flush();
dest.close();
is.close();
}
zip.close();
}
} catch (Exception e) {
Log.e("ERROR: ", "" + e.getMessage());
}
}
Just have a look at http://www.lingala.net/zip4j/download.php , this library file is quick and good .
And you have the short explanation of using the library here
FYI : Here is the another references .
And regarding your code , I have also tried this snippet in my project already but it was ignoring small images while unzipping , so i used the above library . Now i could get it re-solved .

Cannot delete zip file after unzipping?

I am facing an unusal issue.I am building a tool which is scheduled to run every 5 mins.
It will pick up the zip files from a particular directory and extract files (depending on the file name) to a destination. I am using zipentry to get each filename in zip file and then extracting as required then I back them (zip files, once I finish all the files in a zip) to a particular directory and then delete the zip file. But sometimes (not always) the zip files do not get deleted. Since I am using fileutils.forcedelete(). I am getting an exception: unable to delete file. So I changed to the code to using fileutils.forcedeleteonexit() still some files remain in the source.
Here is a sample of my code:
sourceFile=new file(zipfile);
zipFile = new ZipFile(sourceFile);
zEnum = (Enumeration<ZipEntry>) zipFile.entries();
for (int a = 0; a < zipFile.size(); a++)
{
ZipEntry zE = zEnum.nextElement();
//Function uses zip4j for extracting. No streams used.
extract(String sourceZipFile, String fileNameToExtract, String outputFolder);
}
//I tried it with finally either
zipFile.close();
//Using fileutils to copy. No streams used.
copyFile(sourceFile, backup);
FileUtils.forceDeleteOnExit(sourceFile);
There are no streams used but I am getting a lock on files sometimes (not always).
What seems to be the bug here? Is it the zip4j extraction that is causing the problem or anything else? I am using zip4j 1.3.1.
I think your problem related with OS file buffers, that sometimes are not flushed when you are trying to delete file.
Did you try to use sourceFile.deleteOnExit() instead FileUtils.forceDeleteOnExit(sourceFile)?
Also you can try to check sourceFile.canWrite before deleting (may be it may helps)
You can also try to use FileInputStream() before deleting:
FileInputStream fi = new FileInputStream(sourceFile);
fi.getFD().sync();
Use apache-commons IO's FileDeleteStrategy. Something like:
FileDeleteStrategy.FORCE.delete(file);
Update:
It should be the way IO is being handled in your application. I have written simple code which copies a zip file to a temporary zip, deflates the temporary zip and after few seconds deletes it. Here you go:
public class ZipTest {
private static String dirPath = "/home/ubuntuuser/Desktop/";
public static void main(String[] args) throws Exception {
File myzip = new File(dirPath + "content.zip");
String tempFileStr = dirPath + "content_temp.zip";
File tempFile = new File(tempFileStr);
String unzipFolderStr = dirPath + "unzip";
copyUsingChannels(myzip, tempFile);
// copyUsingStreams(myzip, tempFile);
unZip(tempFileStr, unzipFolderStr);
Thread.sleep(3000);
tempFile.delete();
}
private static void copyUsingStreams(File myzip, File tempFile)
throws IOException, FileNotFoundException {
byte[] barray = new byte[1024];
if (!tempFile.exists())
{
tempFile.createNewFile();
}
FileOutputStream fos = new FileOutputStream(tempFile);
FileInputStream fis = new FileInputStream(myzip);
int length = 0;
while ((length = fis.read(barray)) != -1)
{
fos.write(barray, 0, length);
}
fis.close();
fos.close();
}
public static void copyUsingChannels(final File srcFile, final File destFile) throws Exception
{
if (!destFile.exists())
{
destFile.createNewFile();
}
FileChannel source = new FileInputStream(srcFile).getChannel();
FileChannel destination = new FileOutputStream(destFile).getChannel();
source.transferTo(0, source.size(), destination);
source.close();
destination.close();
}
private static void unZip(String zipFile, String outputFolder) throws Exception {
byte[] buffer = new byte[1024];
File folder = new File(outputFolder);
if (!folder.exists()) {
folder.mkdir();
}
ZipInputStream zis = new ZipInputStream(new FileInputStream(zipFile));
ZipEntry ze = zis.getNextEntry();
while (ze != null) {
String fileName = ze.getName();
File newFile = new File(outputFolder + File.separator + fileName);
System.out.println("file unzip : " + newFile.getAbsoluteFile());
new File(newFile.getParent()).mkdirs();
if (ze.isDirectory())
{
newFile.mkdir();
ze = zis.getNextEntry();
continue;
}
FileOutputStream fos = new FileOutputStream(newFile);
int len;
while ((len = zis.read(buffer)) > 0) {
fos.write(buffer, 0, len);
}
fos.close();
ze = zis.getNextEntry();
}
zis.closeEntry();
zis.close();
}
}

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