Zip4j比jdk自带的zip类的好处是支持密码，操作更加简单，而且只要导入1个jar，不依赖于其他类库，所以使用非常方便：
1.最简单的方式压缩一堆文件到zip里：
try {
// Initiate ZipFile object with the path/name of the zip file.
// Zip file may not necessarily exist. If zip file exists, then
// all these files are added to the zip file. If zip file does not
// exist, then a new zip file is created with the files mentioned
ZipFile zipFile = new ZipFile("c:\\ZipTest\\AddFilesDeflateComp.zip");
// Build the list of files to be added in the array list
// Objects of type File have to be added to the ArrayList
ArrayList filesToAdd = new ArrayList();
filesToAdd.add(new File("c:\\ZipTest\\sample.txt"));
filesToAdd.add(new File("c:\\ZipTest\\myvideo.avi"));
filesToAdd.add(new File("c:\\ZipTest\\mysong.mp3"));
// Initiate Zip Parameters which define various properties such
// as compression method, etc. More parameters are explained in other
// examples
ZipParameters parameters = new ZipParameters();
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE); // set compression method to deflate compression
// Set the compression level. This value has to be in between 0 to 9
// Several predefined compression levels are available
// DEFLATE_LEVEL_FASTEST - Lowest compression level but higher speed of compression
// DEFLATE_LEVEL_FAST - Low compression level but higher speed of compression
// DEFLATE_LEVEL_NORMAL - Optimal balance between compression level/speed
// DEFLATE_LEVEL_MAXIMUM - High compression level with a compromise of speed
// DEFLATE_LEVEL_ULTRA - Highest compression level but low speed
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
// Now add files to the zip file
// Note: To add a single file, the method addFile can be used
// Note: If the zip file already exists and if this zip file is a split file
// then this method throws an exception as Zip Format Specification does not
// allow updating split zip files
zipFile.addFiles(filesToAdd, parameters);
} catch (ZipException e) {
e.printStackTrace();
}
2.在zip中添加文件夹，把文件压缩到里面：
try {
ZipFile zipFile = new ZipFile("c:\\ZipTest\\AddFilesDeflateComp.zip");
ArrayList filesToAdd = new ArrayList();
filesToAdd.add(new File("c:\\ZipTest\\sample.txt"));
filesToAdd.add(new File("c:\\ZipTest\\myvideo.avi"));
filesToAdd.add(new File("c:\\ZipTest\\mysong.mp3"));
ZipParameters parameters = new ZipParameters();
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE); // set compression method to deflate compression
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
// Sets the folder in the zip file to which these new files will be added.
// In this example, test2 is the folder to which these files will be added.
// Another example: if files were to be added to a directory test2/test3, then
// below statement should be parameters.setRootFolderInZip("test2/test3/");
parameters.setRootFolderInZip("test2/");
// Now add files to the zip file
zipFile.addFiles(filesToAdd, parameters);
} catch (ZipException e) {
e.printStackTrace();
}
3.给压缩文件加密码：
// Set the encryption flag to true
// If this is set to false, then the rest of encryption properties are ignored
parameters.setEncryptFiles(true);
// Set the encryption method to AES Zip Encryption
parameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_AES);
// Set AES Key strength. Key strengths available for AES encryption are:
// AES_STRENGTH_128 - For both encryption and decryption
// AES_STRENGTH_192 - For decryption only
// AES_STRENGTH_256 - For both encryption and decryption
// Key strength 192 cannot be used for encryption. But if a zip file already has a
// file encrypted with key strength of 192, then Zip4j can decrypt this file
parameters.setAesKeyStrength(Zip4jConstants.AES_STRENGTH_256);
// Set password
parameters.setPassword("test123!");
// Now add files to the zip file
// Note: To add a single file, the method addFile can be used
// Note: If the zip file already exists and if this zip file is a split file
// then this method throws an exception as Zip Format Specification does not
// allow updating split zip files
zipFile.addFiles(filesToAdd, parameters);
可以通过语句
parameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_STANDARD);
设置不同的加密算法。
4.将文件夹以及里面所有文件/文件夹添加到zip中：
try {
// Initiate ZipFile object with the path/name of the zip file.
ZipFile zipFile = new ZipFile("c:\\ZipTest\\AddFolder.zip");
// Folder to add
String folderToAdd = "c:\\FolderToAdd";
// Initiate Zip Parameters which define various properties such
// as compression method, etc.
ZipParameters parameters = new ZipParameters();
// set compression method to store compression
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE);
// Set the compression level
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
// Add folder to the zip file
zipFile.addFolder(folderToAdd, parameters);
} catch (ZipException e) {
e.printStackTrace();
}
这个方法简单又实用。
5.将流压缩到zip中：
InputStream is = null;
try {
ZipFile zipFile = new ZipFile("c:\\ZipTest\\AddStreamToZip.zip");
ZipParameters parameters = new ZipParameters();
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE);
// below two parameters have to be set for adding content to a zip file
// directly from a stream
// this would be the name of the file for this entry in the zip file
parameters.setFileNameInZip("yourfilename.txt");
// we set this flag to true. If this flag is true, Zip4j identifies that
// the data will not be from a file but directly from a stream
parameters.setSourceExternalStream(true);
// For this example I use a FileInputStream but in practise this can be
// any inputstream
is = new FileInputStream("filetoadd.txt");
// Creates a new entry in the zip file and adds the content to the zip file
zipFile.addStream(is, parameters);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
6.压缩成多个分卷：
try{
ZipFile zipFile = new ZipFile("./iam.zip");
ZipParameters parameters = new ZipParameters();
zipFile.createZipFile(new File("Alec Finn - The Water Is Wide.mp3"), parameters,true, 65537);
}catch (Exception e) {
e.printStackTrace();
}
7.从文件创建压缩分卷：
try {
// Initiate ZipFile object with the path/name of the zip file.
ZipFile zipFile = new ZipFile("c:\\ZipTest\\CreateSplitZipFileFromFolder.zip");
// Initiate Zip Parameters which define various properties such
// as compression method, etc.
ZipParameters parameters = new ZipParameters();
// set compression method to store compression
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE);
// Set the compression level. This value has to be in between 0 to 9
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
// Create a split file by setting splitArchive parameter to true
// and specifying the splitLength. SplitLenth has to be greater than
// 65536 bytes
// Please note: If the zip file already exists, then this method throws an
// exception
zipFile.createZipFileFromFolder("C:\\ZipTest", parameters, true, 10485760);
} catch (ZipException e) {
e.printStackTrace();
} 8.从输出流创建zip文件：
ZipOutputStream outputStream = null;
InputStream inputStream = null;
try {
// Prepare the files to be added
ArrayList filesToAdd = new ArrayList();
filesToAdd.add(new File("c:\\ZipTest\\sample.txt"));
filesToAdd.add(new File("c:\\ZipTest\\myvideo.avi"));
filesToAdd.add(new File("c:\\ZipTest\\mysong.mp3"));
//Initiate output stream with the path/file of the zip file
//Please note that ZipOutputStream will overwrite zip file if it already exists
outputStream = new ZipOutputStream(new FileOutputStream(new File("c:\\ZipTest\\CreateZipFileWithOutputStreams.zip")));
// Initiate Zip Parameters which define various properties such
// as compression method, etc. More parameters are explained in other
// examples
ZipParameters parameters = new ZipParameters();
//Deflate compression or store(no compression) can be set below
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE);
// Set the compression level. This value has to be in between 0 to 9
// Several predefined compression levels are available
// DEFLATE_LEVEL_FASTEST - Lowest compression level but higher speed of compression
// DEFLATE_LEVEL_FAST - Low compression level but higher speed of compression
// DEFLATE_LEVEL_NORMAL - Optimal balance between compression level/speed
// DEFLATE_LEVEL_MAXIMUM - High compression level with a compromise of speed
// DEFLATE_LEVEL_ULTRA - Highest compression level but low speed
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
//This flag defines if the files have to be encrypted.
//If this flag is set to false, setEncryptionMethod, as described below,
//will be ignored and the files won't be encrypted
parameters.setEncryptFiles(true);
//Zip4j supports AES or Standard Zip Encryption (also called ZipCrypto)
//If you choose to use Standard Zip Encryption, please have a look at example
//as some additional steps need to be done while using ZipOutputStreams with
//Standard Zip Encryption
parameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_AES);
//If AES encryption is used, this defines the key strength
parameters.setAesKeyStrength(Zip4jConstants.AES_STRENGTH_256);
//self descriptive
parameters.setPassword("YourPassword");
//Now we loop through each file and read this file with an inputstream
//and write it to the ZipOutputStream.
for (int i = 0; i < filesToAdd.size(); i++) {
File file = (File)filesToAdd.get(i);
//This will initiate ZipOutputStream to include the file
//with the input parameters
outputStream.putNextEntry(file,parameters);
//If this file is a directory, then no further processing is required
//and we close the entry (Please note that we do not close the outputstream yet)
if (file.isDirectory()) {
outputStream.closeEntry();
continue;
}
//Initialize inputstream
inputStream = new FileInputStream(file);
byte[] readBuff = new byte[4096];
int readLen = -1;
//Read the file content and write it to the OutputStream
while ((readLen = inputStream.read(readBuff)) != -1) {
outputStream.write(readBuff, 0, readLen);
}
//Once the content of the file is copied, this entry to the zip file
//needs to be closed. ZipOutputStream updates necessary header information
//for this file in this step
outputStream.closeEntry();
inputStream.close();
}
//ZipOutputStream now writes zip header information to the zip file
outputStream.finish();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
} 9.解压所有文件：
try {
// Initiate ZipFile object with the path/name of the zip file.
ZipFile zipFile = new ZipFile("c:\\ZipTest\\ExtractAllFiles.zip");
// Extracts all files to the path specified
zipFile.extractAll("c:\\ZipTest");
} catch (ZipException e) {
e.printStackTrace();
} 10.解压单个文件：
try {
// Initiate ZipFile object with the path/name of the zip file.
ZipFile zipFile = new ZipFile("c:\\ZipTest\\ExtractSingleFile.zip");
// Check to see if the zip file is password protected
if (zipFile.isEncrypted()) {
// if yes, then set the password for the zip file
zipFile.setPassword("test123!");
}
// Specify the file name which has to be extracted and the path to which
// this file has to be extracted
zipFile.extractFile("Ronan_Keating_-_In_This_Life.mp3", "c:\\ZipTest\\");
// Note that the file name is the relative file name in the zip file.
// For example if the zip file contains a file "mysong.mp3" in a folder
// "FolderToAdd", then extraction of this file can be done as below:
zipFile.extractFile("FolderToAdd\\myvideo.avi", "c:\\ZipTest\\");
} catch (ZipException e) {
e.printStackTrace();
} 例子来源于Zip4j，展开附件可以看到更多实例和源码。