问题
I have zip file which contains some other zip files.
For example, the mail file is abc.zip and it contains xyz.zip, class1.java, class2.java. And xyz.zip contains the file class3.java and class4.java.
So I need to extract the zip file using Java to a folder that should contain class1.java, class2.java, class3.java and class4.java.
回答1:
Warning, the code here is ok for trusted zip files, there's no path validation before write which may lead to security vulnerability as described in zip-slip-vulnerability if you use it to deflate an uploaded zip file from unknown client.
This solution is very similar to the previous solutions already posted, but this one recreates the proper folder structure on unzip.
static public void extractFolder(String zipFile) throws ZipException, IOException
{
System.out.println(zipFile);
int BUFFER = 2048;
File file = new File(zipFile);
ZipFile zip = new ZipFile(file);
String newPath = zipFile.substring(0, zipFile.length() - 4);
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();
}
if (currentEntry.endsWith(".zip"))
{
// found a zip file, try to open
extractFolder(destFile.getAbsolutePath());
}
}
}
回答2:
Here's some untested code base on some old code I had that unzipped files.
public void doUnzip(String inputZip, String destinationDirectory)
throws IOException {
int BUFFER = 2048;
List zipFiles = new ArrayList();
File sourceZipFile = new File(inputZip);
File unzipDestinationDirectory = new File(destinationDirectory);
unzipDestinationDirectory.mkdir();
ZipFile zipFile;
// Open Zip file for reading
zipFile = new ZipFile(sourceZipFile, ZipFile.OPEN_READ);
// Create an enumeration of the entries in the zip file
Enumeration zipFileEntries = zipFile.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(unzipDestinationDirectory, currentEntry);
destFile = new File(unzipDestinationDirectory, destFile.getName());
if (currentEntry.endsWith(".zip")) {
zipFiles.add(destFile.getAbsolutePath());
}
// grab file's parent directory structure
File destinationParent = destFile.getParentFile();
// create the parent directory structure if needed
destinationParent.mkdirs();
try {
// extract file if not a directory
if (!entry.isDirectory()) {
BufferedInputStream is =
new BufferedInputStream(zipFile.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 (IOException ioe) {
ioe.printStackTrace();
}
}
zipFile.close();
for (Iterator iter = zipFiles.iterator(); iter.hasNext();) {
String zipName = (String)iter.next();
doUnzip(
zipName,
destinationDirectory +
File.separatorChar +
zipName.substring(0,zipName.lastIndexOf(".zip"))
);
}
}
回答3:
I take ca.anderson4 and remove the List zipFiles and rewrite a little bit, this is what i got:
public class Unzip {
public void unzip(String zipFile) throws ZipException,
IOException {
System.out.println(zipFile);;
int BUFFER = 2048;
File file = new File(zipFile);
ZipFile zip = new ZipFile(file);
String newPath = zipFile.substring(0, zipFile.length() - 4);
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();
}
if (currentEntry.endsWith(".zip")) {
// found a zip file, try to open
unzip(destFile.getAbsolutePath());
}
}
}
public static void main(String[] args) {
Unzip unzipper=new Unzip();
try {
unzipper.unzip("test/test.zip");
} catch (ZipException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
I tested and it works
回答4:
In testing I noticed File.mkDirs() does not work under Windows...
/** * for a given full path name recreate all parent directories **/
private void createParentHierarchy(String parentName) throws IOException {
File parent = new File(parentName);
String[] parentsStrArr = parent.getAbsolutePath().split(File.separator == "/" ? "/" : "\\\\");
//create the parents of the parent
for(int i=0; i < parentsStrArr.length; i++){
StringBuffer currParentPath = new StringBuffer();
for(int j = 0; j < i; j++){
currParentPath.append(parentsStrArr[j]+File.separator);
}
File currParent = new File(currParentPath.toString());
if(!currParent.isDirectory()){
boolean created = currParent.mkdir();
if(isVerbose)log("creating directory "+currParent.getAbsolutePath());
}
}
//create the parent itself
if(!parent.isDirectory()){
boolean success = parent.mkdir();
}
}
回答5:
Modified as i needed then mixed in a bit of the best answers. This version will:
Recursively Extract a zip to given location
Create empty directories
Close zip properly
public static void unZipAll(File source, File destination) throws IOException
{
System.out.println("Unzipping - " + source.getName());
int BUFFER = 2048;
ZipFile zip = new ZipFile(source);
try{
destination.getParentFile().mkdirs();
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(destination, 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 = null;
FileOutputStream fos = null;
BufferedOutputStream dest = null;
try{
is = new BufferedInputStream(zip.getInputStream(entry));
int currentByte;
// establish buffer for writing file
byte data[] = new byte[BUFFER];
// write the current file to disk
fos = new FileOutputStream(destFile);
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);
}
} catch (Exception e){
System.out.println("unable to extract entry:" + entry.getName());
throw e;
} finally{
if (dest != null){
dest.close();
}
if (fos != null){
fos.close();
}
if (is != null){
is.close();
}
}
}else{
//Create directory
destFile.mkdirs();
}
if (currentEntry.endsWith(".zip"))
{
// found a zip file, try to extract
unZipAll(destFile, destinationParent);
if(!destFile.delete()){
System.out.println("Could not delete zip");
}
}
}
} catch(Exception e){
e.printStackTrace();
System.out.println("Failed to successfully unzip:" + source.getName());
} finally {
zip.close();
}
System.out.println("Done Unzipping:" + source.getName());
}
回答6:
One should CLOSE zip file after unzip.
static public void extractFolder(String zipFile) throws ZipException, IOException
{
System.out.println(zipFile);
int BUFFER = 2048;
File file = new File(zipFile);
ZipFile zip = new ZipFile(file);
try
{
...code from other answers ( ex. NeilMonday )...
}
finally
{
zip.close();
}
}
回答7:
Same as NeilMonday's answer, but extracts empty directories:
static public void extractFolder(String zipFile) throws ZipException, IOException
{
System.out.println(zipFile);
int BUFFER = 2048;
File file = new File(zipFile);
ZipFile zip = new ZipFile(file);
String newPath = zipFile.substring(0, zipFile.length() - 4);
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();
}
else{
destFile.mkdirs()
}
if (currentEntry.endsWith(".zip"))
{
// found a zip file, try to open
extractFolder(destFile.getAbsolutePath());
}
}
}
回答8:
File dir = new File("BASE DIRECTORY PATH");
FileFilter ff = new FileFilter() {
@Override
public boolean accept(File f) {
//only want zip files
return (f.isFile() && f.getName().toLowerCase().endsWith(".zip"));
}
};
File[] list = null;
while ((list = dir.listFiles(ff)).length > 0) {
File file1 = list[0];
//TODO unzip the file to the base directory
}
来源：https://stackoverflow.com/questions/981578/how-to-unzip-files-recursively-in-java