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Extracting PDF inside a Zip inside a Zip

i have checked everywhere online and stackoverflow and could not find a match specific to this issue.
I am trying to extract a pdf file that is located in a zip file that is inside a zip file (nested zips).
Re-calling the method i am using to extract does not work nor does changing the whole program to accept Inputstreams instead of how i am doing it below.
The .pdf file inside the nested zip is just skipped at this stage
public static void main(String[] args)
{
try
{
//Paths
String basePath = "C:\\Users\\user\\Desktop\\Scan\\";
File lookupDir = new File(basePath + "Data\\");
String doneFolder = basePath + "DoneUnzipping\\";
File[] directoryListing = lookupDir.listFiles();
for (int i = 0; i < directoryListing.length; i++)
{
if (directoryListing[i].isFile()) //there's definately a file
{
//Save the current file's path
String pathOrigFile = directoryListing[i].getAbsolutePath();
Path origFileDone = Paths.get(pathOrigFile);
Path newFileDone = Paths.get(doneFolder + directoryListing[i].getName());
//unzip it
if(directoryListing[i].getName().toUpperCase().endsWith(ZIP_EXTENSION)) //ZIP files
{
unzip(directoryListing[i].getAbsolutePath(), DESTINATION_DIRECTORY + directoryListing[i].getName());
//move to the 'DoneUnzipping' folder
Files.move(origFileDone, newFileDone);
}
}
}
} catch (Exception e)
{
e.printStackTrace(System.out);
}
}
private static void unzip(String zipFilePath, String destDir)
{
//buffer for read and write data to file
byte[] buffer = new byte[BUFFER_SIZE];
try (ZipInputStream zis = new ZipInputStream(new FileInputStream(zipFilePath)))
{
FileInputStream fis = new FileInputStream(zipFilePath);
ZipEntry ze = zis.getNextEntry();
while(ze != null)
{
String fileName = ze.getName();
int index = fileName.lastIndexOf("/");
String newFileName = fileName.substring(index + 1);
File newFile = new File(destDir + File.separator + newFileName);
//Zips inside zips
if(fileName.toUpperCase().endsWith(ZIP_EXTENSION))
{
ZipInputStream innerZip = new ZipInputStream(zis);
ZipEntry innerEntry = null;
while((innerEntry = innerZip.getNextEntry()) != null)
{
System.out.println("The file: " + fileName);
if(fileName.toUpperCase().endsWith("PDF"))
{
FileOutputStream fos = new FileOutputStream(newFile);
int len;
while ((len = innerZip.read(buffer)) > 0)
{
fos.write(buffer, 0, len);
}
fos.close();
}
}
}
//close this ZipEntry
zis.closeEntry(); // java.io.IOException: Stream Closed
ze = zis.getNextEntry();
}
//close last ZipEntry
zis.close();
fis.close();
} catch (IOException e)
{
e.printStackTrace();
}
}

The solution to this is not as obvious as it seems. Despite writing a few zip utilities myself some time ago, getting zip entries from inside another zip file only seems obvious in retrospect
(and I also got the java.io.IOException: Stream Closed on my first attempt).
The Java classes for ZipFile and ZipInputStream really direct your thinking into using the file system, but it is not required.
The functions below will scan a parent-level zip file, and continue scanning until it finds an entry with a specified name. (Nearly) everything is done in-memory.
Naturally, this can be modified to use different search criteria, find multiple file types, etc. and take different actions, but this at least demonstrates the basic technique in question -- zip files inside of zip files -- no guarantees on other aspects of the code, and someone more savvy could most likely improve the style.
final static String ZIP_EXTENSION = ".zip";
public static byte[] getOnePDF() throws IOException
{
final File source = new File("/path/to/MegaData.zip");
final String nameToFind = "FindThisFile.pdf";
final ByteArrayOutputStream mem = new ByteArrayOutputStream();
try (final ZipInputStream in = new ZipInputStream(new BufferedInputStream(new FileInputStream(source))))
{
digIntoContents(in, nameToFind, mem);
}
// Save to disk, if you want
// copy(new ByteArrayInputStream(mem.toByteArray()), new FileOutputStream(new File("/path/to/output.pdf")));
// Otherwise, just return the binary data
return mem.toByteArray();
}
private static void digIntoContents(final ZipInputStream in, final String nameToFind, final ByteArrayOutputStream mem) throws IOException
{
ZipEntry entry;
while (null != (entry = in.getNextEntry()))
{
final String name = entry.getName();
// Found the file we are looking for
if (name.equals(nameToFind))
{
copy(in, mem);
return;
}
// Found another zip file
if (name.toUpperCase().endsWith(ZIP_EXTENSION.toUpperCase()))
{
digIntoContents(new ZipInputStream(new ByteArrayInputStream(getZipEntryFromMemory(in))), nameToFind, mem);
}
}
}
private static byte[] getZipEntryFromMemory(final ZipInputStream in) throws IOException
{
final ByteArrayOutputStream mem = new ByteArrayOutputStream();
copy(in, mem);
return mem.toByteArray();
}
// General purpose, reusable, utility function
// OK for binary data (bad for non-ASCII text, use Reader/Writer instead)
public static void copy(final InputStream from, final OutputStream to) throws IOException
{
final int bufferSize = 4096;
final byte[] buf = new byte[bufferSize];
int len;
while (0 < (len = from.read(buf)))
{
to.write(buf, 0, len);
}
to.flush();
}

Your question asks how to use java (by implication in windows) to extract a pdf from a zip inside another outer zip.
In many systems including windows it is a single line command that will depend on the location of source and target folders, however using the shortest example of current downloads folder it would be in a shell as simple as
tar -xf "german (2).zip" && tar -xf "german.zip" && german.pdf
to shell the command in windows see
How do I execute Windows commands in Java?
The default pdf viewer can open the result so Windows Edge or in my case SumatraPDF
There is generally no point in putting a pdf inside a zip because it cannot be run in there. So single nesting would be advisable if needed for download transportation.
There is no need to add a password to the zip because PDF uses its own password for opening. Thus unwise to add two levels of complexity. Keep it simple.
If you have multiple zips nested inside multiple zips with multiple pdfs in each then you have to be more specific by filtering names. However avoid that extra onion skin where possible.
\Downloads>tar -xf "german (2).zip" "both.zip" && tar -xf "both.zip" "English language.pdf"
You could complicate that by run in a memory or temp folder but it is reliable and simple to use the native file system so consider without Java its fastest to run
CD /D "C:/Users/user/Desktop/Scan/DoneUnzipping" && for %f in (..\Data\*.zip) do tar -xf "%f" "*.zip" && for %f in (*.zip) do tar -xf "%f" "*.pdf" && del "*.zip"
This will extract all inner zips into working folder then extract all PDFs and remove all the essential temporary zips. The source double zips will not be deleted simply touched.

The line that causes your problem looks to be auto-close block you have created when reading the inner zip:
try(ZipInputStream innerZip = new ZipInputStream(fis)) {
...
}
Several likely issues: firstly it is reading the wrong stream - fis not the existing zis.
Secondly, you shouldn't use try-with-resources for auto-close on innerZip as this implicitly calls innerZip.close() when exiting the block. If you view the source code of ZipInputStream via a good IDE you should see (eventually) that ZipInputStream extends InflaterInputStream which itself extends FilterInputStream. A call to innerZip.close() will close the underlying outer stream zis (fis in your case) hence stream is closed when you resume the next entry of the outer zip.
Therefore remove the try() block and add use of zis:
ZipInputStream innerZip = new ZipInputStream(zis);
Use try-catch block only for the outermost file handling:
try (ZipInputStream zis = new ZipInputStream(new FileInputStream(zipFilePath))) {
ZipEntry ze = zis.getNextEntry();
...
}
Thirdly, you appear to be copying the wrong stream when extracting a PDF - use innerZip not outer zis. The code will never extract PDF as these 2 lines can never be true at the same time because a file ending ZIP will never end PDF too:
if(fileName.toUpperCase().endsWith(ZIP_EXTENSION)) {
...
// You want innerEntry.getName() here
if(fileName.toUpperCase().endsWith("PDF"))
You should be able to switch to one line Files.copy and make use of the PDF filename not zip filename:
if(innerEntry.getName().toUpperCase().endsWith("PDF")) {
Path newFile = Paths.get(destDir + '-'+innerEntry.getName().replace("/", "-"));
System.out.println("Files.copy to " + newFile);
Files.copy(innerZip, newFile);
}

Java selectively copy files from a zip such that file timestamp should be preserved

I have followed following approach to decompress a zip using apache commons compress:
But since I am using OutputStream & IOUtils.copy(ais, os); (code below) to unzip and copy file, the timestamp is not preserved. Is there another way to directly copy the file from the zip such that file timestamp can be preserved.
try (ArchiveInputStream ais =
asFactory.createArchiveInputStream(
new BufferedInputStream(
new FileInputStream(archive)))) {
System.out.println("Extracting!");
ArchiveEntry ae;
while ((ae = ais.getNextEntry()) != null) {
// check if file needs to be extracted {}
if(!extract())
continue;
if (ae.isDirectory()) {
File dir = new File(archive.getParentFile(), ae.getName());
dir.mkdirs();
continue;
}
File f = new File(archive.getParentFile(), ae.getName());
File parent = f.getParentFile();
parent.mkdirs();
try (OutputStream os = new FileOutputStream(f)) {
IOUtils.copy(ais, os);
os.close();
} catch (IOException innerIoe) {
...
}
}
ais.close();
if (!archive.delete()) {
System.out.printf("Could not remove archive %s%n",
archive.getName());
archive.deleteOnExit();
}
} catch (IOException ioe) {
...
}
EDIT: With the help of jbx's answer below, following change will make it work.
IOUtils.copy(ais, os);
os.close();
outFile.setLastModified(entry.getLastModifiedTime().toMillis()); // this line

You could set the lastModifiedTime file attribute using NIO. Do it to the file exactly after you write it (after you close it). The operating system would have marked its last modified time to the current time at that point.
https://docs.oracle.com/javase/tutorial/essential/io/fileAttr.html
You will need to get the last modified time from the zip file, so maybe using NIO's
Zip Filesystem Provider` to browse and extract files from the archive would be better than your current approach (unless the APIs you are using provide you the same information).
https://docs.oracle.com/javase/7/docs/technotes/guides/io/fsp/zipfilesystemprovider.html

How to Unzip the file genrated in one folder and add one tag in XML(XMLfile is inside zip) and again zip the file using Java and Selenium [duplicate]

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I looked at the default Zip library that comes with the JDK and the Apache compression libs and I am unhappy with them for 3 reasons:
They are bloated and have bad API design. I have to write 50 lines of boiler plate byte array output, zip input, file out streams and close relevant streams and catch exceptions and move byte buffers on my own? Why can't I have a simple API that looks like this Zipper.unzip(InputStream zipFile, File targetDirectory, String password = null) and Zipper.zip(File targetDirectory, String password = null) that just works?
It seems zipping unzipping destroys file meta-data and password handling is broken.
Also, all the libraries I tried were 2-3x slow compared to the command line zip tools I get with UNIX?
For me (2) and (3) are minor points but I really want a good tested library with a one-line interface.

I know its late and there are lots of answers but this zip4j is one of the best libraries for zipping I have used. Its simple (no boiler code) and can easily handle password protected files.
import net.lingala.zip4j.exception.ZipException;
import net.lingala.zip4j.core.ZipFile;
public static void unzip(){
String source = "some/compressed/file.zip";
String destination = "some/destination/folder";
String password = "password";
try {
ZipFile zipFile = new ZipFile(source);
if (zipFile.isEncrypted()) {
zipFile.setPassword(password);
}
zipFile.extractAll(destination);
} catch (ZipException e) {
e.printStackTrace();
}
}
The Maven dependency is:
<dependency>
<groupId>net.lingala.zip4j</groupId>
<artifactId>zip4j</artifactId>
<version>1.3.2</version>
</dependency>

In Java 8, with Apache Commons-IO's IOUtils you can do this:
try (java.util.zip.ZipFile zipFile = new ZipFile(file)) {
Enumeration<? extends ZipEntry> entries = zipFile.entries();
while (entries.hasMoreElements()) {
ZipEntry entry = entries.nextElement();
File entryDestination = new File(outputDir, entry.getName());
if (entry.isDirectory()) {
entryDestination.mkdirs();
} else {
entryDestination.getParentFile().mkdirs();
try (InputStream in = zipFile.getInputStream(entry);
OutputStream out = new FileOutputStream(entryDestination)) {
IOUtils.copy(in, out);
}
}
}
}
It's still some boilerplate code, but it has only 1 non-exotic dependency: Commons-IO
In Java 11 and higher, better options might be available, see ZhekaKozlov's comment.

Extract zip file and all its subfolders, using only the JDK:
private void extractFolder(String zipFile,String extractFolder)
{
try
{
int BUFFER = 2048;
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();
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();
}
}
}
catch (Exception e)
{
Log("ERROR: "+e.getMessage());
}
}
Zip files and all its subfolders:
private void addFolderToZip(File folder, ZipOutputStream zip, String baseName) throws IOException {
File[] files = folder.listFiles();
for (File file : files) {
if (file.isDirectory()) {
addFolderToZip(file, zip, baseName);
} else {
String name = file.getAbsolutePath().substring(baseName.length());
ZipEntry zipEntry = new ZipEntry(name);
zip.putNextEntry(zipEntry);
IOUtils.copy(new FileInputStream(file), zip);
zip.closeEntry();
}
}
}

Another option that you can check out is zt-zip available from Maven central and project page at https://github.com/zeroturnaround/zt-zip
It has the standard packing and unpacking functionality (on streams and on filesystem) + lots of helper methods to test for files in an archive or add/remove entries.

Full Implementation to Zip/Unzip a Folder/File with zip4j
Add this dependency to your build manager. Or, download the latest JAR file from here and add it to your project build path. The class bellow can compress and extract any file or folder with or without password protection-
import java.io.File;
import net.lingala.zip4j.model.ZipParameters;
import net.lingala.zip4j.util.Zip4jConstants;
import net.lingala.zip4j.core.ZipFile;
public class Compressor {
public static void zip (String targetPath, String destinationFilePath, String password) {
try {
ZipParameters parameters = new ZipParameters();
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE);
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
if (password.length() > 0) {
parameters.setEncryptFiles(true);
parameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_AES);
parameters.setAesKeyStrength(Zip4jConstants.AES_STRENGTH_256);
parameters.setPassword(password);
}
ZipFile zipFile = new ZipFile(destinationFilePath);
File targetFile = new File(targetPath);
if (targetFile.isFile()) {
zipFile.addFile(targetFile, parameters);
} else if (targetFile.isDirectory()) {
zipFile.addFolder(targetFile, parameters);
} else {
//neither file nor directory
}
} catch (Exception e) {
e.printStackTrace();
}
}
public static void unzip(String targetZipFilePath, String destinationFolderPath, String password) {
try {
ZipFile zipFile = new ZipFile(targetZipFilePath);
if (zipFile.isEncrypted()) {
zipFile.setPassword(password);
}
zipFile.extractAll(destinationFolderPath);
} catch (Exception e) {
e.printStackTrace();
}
}
/**/ /// for test
public static void main(String[] args) {
String targetPath = "target\\file\\or\\folder\\path";
String zipFilePath = "zip\\file\\Path";
String unzippedFolderPath = "destination\\folder\\path";
String password = "your_password"; // keep it EMPTY<""> for applying no password protection
Compressor.zip(targetPath, zipFilePath, password);
Compressor.unzip(zipFilePath, unzippedFolderPath, password);
}/**/
}
For more detailed usage, please see here.

A very nice project is TrueZip.
TrueZIP is a Java based plug-in framework for virtual file systems (VFS) which provides transparent access to archive files as if they were just plain directories
For example (from the website):
File file = new TFile("archive.tar.gz/README.TXT");
OutputStream out = new TFileOutputStream(file);
try {
// Write archive entry contents here.
...
} finally {
out.close();
}

Another option is JZlib. In my experience, it's less "file-centered" than zip4J, so if you need to work on in-memory blobs rather than files, you may want to take a look at it.

There's a full example here for zipping and unzipping files recursively:
http://developer-tips.hubpages.com/hub/Zipping-and-Unzipping-Nested-Directories-in-Java-using-Apache-Commons-Compress

Did you have a look at http://commons.apache.org/vfs/ ? It claims to simplify a lot of things for you. But I've never used it in a project.
I also am not aware of Java-Native compression libs other than the JDK or Apache Compression.
I remember once we ripped some features out of Apache Ant - they have a lot of utils for compression / decompression built in.
Sample code with VFS would look like:
File zipFile = ...;
File outputDir = ...;
FileSystemManager fsm = VFS.getManager();
URI zip = zipFile.toURI();
FileObject packFileObject = fsm.resolveFile(packLocation.toString());
FileObject to = fsm.toFileObject(destDir);
FileObject zipFS;
try {
zipFS = fsm.createFileSystem(packFileObject);
fsm.toFileObject(outputDir).copyFrom(zipFS, new AllFileSelector());
} finally {
zipFS.close();
}

How to determine the compression method of a zip file

From a third party I am retrieving .zip files. I want to unzip these to another folder. To this end I found a method that does exactly that, see code below. It iterates through all files and unzips them to another folder. However, when observing the corresponding compression method I found out that this changes for some files. And for some files it states: "invalid compression method", after which it aborts further unzipping of the zip file.
As the compression method seems to change, I suspect I need to set the compression method to the correct one (however that might be a wrong assumption). So rises my question: how to determine the compression method needed?
The code I am using:
public void unZipIt(String zipFile, String outputFolder){
//create output directory is not exists
File folder = new File(OUTPUT_FOLDER);
if(!folder.exists()){
folder.mkdir();
}
FileInputStream fis = null;
ZipInputStream zipIs = null;
ZipEntry zEntry = null;
try
{
fis = new FileInputStream(zipFile);
zipIs = new ZipInputStream(new BufferedInputStream(fis));
while((zEntry = zipIs.getNextEntry()) != null){
System.out.println(zEntry.getMethod());
try{
byte[] tmp = new byte[4*1024];
FileOutputStream fos = null;
String opFilePath = OUTPUT_FOLDER + "\\" + zEntry.getName();
System.out.println("Extracting file to "+opFilePath);
fos = new FileOutputStream(opFilePath);
int size = 0;
while((size = zipIs.read(tmp)) != -1){
fos.write(tmp, 0 , size);
}
fos.flush();
fos.close();
} catch(IOException e){
System.out.println(e.getMessage());
}
}
zipIs.close();
} catch (FileNotFoundException e) {
System.out.println(e.getMessage());
}
catch(IOException ex){
System.out.println(ex.getMessage());
}
}
Currently I am retrieving the following output:
8
Extracting file to C:\Users\nlmeibe2\Documents\Projects\Output_test\SOPHIS_cptyrisk_tradedata_1192_20140616.csv
8
Extracting file to C:\Users\nlmeibe2\Documents\Projects\Output_test\SOPHIS_cptyrisk_underlying_1192_20140616.csv
0
Extracting file to C:\Users\nlmeibe2\Documents\Projects\Output_test\10052013/
12
Extracting file to C:\Users\nlmeibe2\Documents\Projects\Output_test\MRM_Daily_Position_Report_Package_Level_Underlying_View_EQB_v2_COBDATE_2014-06-16_RUNDATETIME_2014-06-17-04h15.csv
invalid compression method
invalid compression method

Since you only print the exception message and not the stack trace (with line numbers), it is impossible to know exactly where the exception is thrown, but I suppose it is not thrown until you actually try to read from the ZipEntry.
If the numbers in your output is the ZIP method, the last entry you encounter is compressed with method 12 (bzip2), which is not supported by the Java ZIP implementation. PKWare (the maintainers of the ZIP format) regularly add new compression methods to the ZIP specification and there are currently some 12-15 (not sure about the exact number) compression methods specified. Java only supports the methods 0 (stored) and 8 (deflated) and will throw an exception with the message "invalid compression method" if you try to decompress a ZIP file using an unsupported compression method.
Both WinZip and the ZIP functions in Windows may use compression methods not supported by the Java API.

Use zEntry.getMethod() to get the compression method
Returns the compression method of the entry, or -1 if not specified.
It will return an int which will be
public static final int STORED
public static final int DEFLATED
or -1 if it don't know the method.
Docs.

java Extracting Zip file

I'm looking for a way to extract Zip file. So far I have tried java.util.zip and org.apache.commons.compress, but both gave a corrupted output.
Basically, the input is a ZIP file contain one single .doc file.
java.util.zip: Output corrupted.
org.apache.commons.compress: Output blank file, but with 2 mb size.
So far only the commercial software like Winrar work perfectly. Is there a java library that make use of this?
This is my method using java.util library:
public void extractZipNative(File fileZip)
{
ZipInputStream zis;
StringBuilder sb;
try {
zis = new ZipInputStream(new FileInputStream(fileZip));
ZipEntry ze = zis.getNextEntry();
byte[] buffer = new byte[(int) ze.getSize()];
FileOutputStream fos = new FileOutputStream(this.tempFolderPath+ze.getName());
int len;
while ((len=zis.read(buffer))>0)
{
fos.write(buffer);
}
fos.flush();
fos.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally
{
if (zis!=null)
{
try { zis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
Many thanks,
Mike

I think your input may be compressed by some "incompatible" zip program like 7zip.
Try investigating first if it can be unpacked with a classical WinZip or such.
Javas zip handling is very well able to deal with zipped archives that come from a "compatible" zip compressor.

It is an error in my code. I need to specify the offset and len of bytes write.

it works for me
ZipFile Vanilla = new ZipFile(new File("Vanilla.zip")); //zipfile defined and needs to be in directory
Enumeration<? extends ZipEntry> entries = Vanilla.entries();// all (files)entries of zip file
while(entries.hasMoreElements()){//runs while there is files in zip
ZipEntry entry = entries.nextElement();//gets name of file in zip
File folderw =new File("tkwgter5834");//creates new directory
InputStream stream = Vanilla.getInputStream(entry);//gets input
FileInputStream inpure= new FileInputStream("Vanilla.zip");//file input stream for zip file to read bytes of file
FileOutputStream outter = new FileOutputStream(new File(folderw +"//"+ entry.toString())); //fileoutput stream creates file inside defined directory(folderw variable) by file's name
outter.write(inpure.readAllBytes());// write into files which were created
outter.close();//closes fileoutput stream
}

Have you tried jUnrar? Perhaps it might work:
https://github.com/edmund-wagner/junrar
If that doesn't work either, I guess your archive is corrupted in some way.

If you know the environment that you're going to be running this code in, I think you're much better off just making a call to the system to unzip it for you. It will be way faster than anything that you implement in java.
I wrote the code to extract a zip file with nested directories and it ran slowly and took a lot of CPU. I wound up replacing it with this:
Runtime.getRuntime().exec(String.format("unzip %s -d %s", archive.getAbsolutePath(), basePath));
That works a lot better.