关于java解压缩文件（rar或者zip）的实现示例 【转】

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Enumeration;
import org.apache.tools.zip.ZipEntry;
import org.apache.tools.zip.ZipFile;
import org.apache.tools.zip.ZipOutputStream;

/**
* <p>
* Title: 解压缩文件
* </p>
* <p>
* Description: 通过apache的zip工具实现解压缩
* </p>
* <p>
* Copyright: Copyright (c) 2010
* </p>
* <p>
* Company: yourcompany
* </p>
*
* @author yourcompany
* @version 1.0
*/
public class CompressFile {
private static CompressFile instance = new CompressFile();

private CompressFile() {
}

public static CompressFile getInstance() {
return instance;
}

/**
* 压缩文件或者文件目录到指定的zip或者rar包
*
* @param inputFilename
* 要压缩的文件或者文件夹，如果是文件夹的话，会将文件夹下的所有文件包含子文件夹的内容进行压缩
* @param zipFilename
* 生成的zip或者rar文件的名称
*/
public synchronized void zip(String inputFilename, String zipFilename)
throws IOException {
zip(new File(inputFilename), zipFilename);
}

/**
* 压缩文件或者文件目录到指定的zip或者rar包，内部调用
*
* @param inputFile
* 参数为文件类型的要压缩的文件或者文件夹
* @param zipFilename
* 生成的zip或者rar文件的名称
* @return void
*/
private synchronized void zip(File inputFile, String zipFilename)
throws IOException {
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
zipFilename));

try {
zip(inputFile, out, "");
} catch (IOException e) {
throw e;
} finally {
out.close();
}
}

/**
* 压缩文件或者文件目录到指定的zip或者rar包
*
* @param inputFile
* 参数为文件类型的要压缩的文件或者文件夹
* @param out
* 输出流
* @param base
* 基文件夹
* @return void
*/
private synchronized void zip(File inputFile, ZipOutputStream out,
String base) throws IOException {
if (inputFile.isDirectory()) {
File[] inputFiles = inputFile.listFiles();
out.putNextEntry(new ZipEntry(base + "/"));
base = base.length() == 0 ? "" : base + "/";
for (int i = 0; i < inputFiles.length; i++) {
zip(inputFiles[i], out, base + inputFiles[i].getName());
}

} else {
if (base.length() > 0) {
out.putNextEntry(new ZipEntry(base));
} else {
out.putNextEntry(new ZipEntry(inputFile.getName()));
}

FileInputStream in = new FileInputStream(inputFile);
try {
int c;
byte[] by = new byte[BUFFEREDSIZE];
while ((c = in.read(by)) != -1) {
out.write(by, 0, c);
}
} catch (IOException e) {
throw e;
} finally {
in.close();
}
}
}

/**
* 解压zip或者rar包的内容到指定的目录下，可以处理其文件夹下包含子文件夹的情况
*
* @param zipFilename
* 要解压的zip或者rar包文件
* @param outputDirectory
* 解压后存放的目录
*/
public synchronized void unzip(String zipFilename, String outputDirectory)
throws IOException {
File outFile = new File(outputDirectory);
if (!outFile.exists()) {
outFile.mkdirs();
}

ZipFile zipFile = new ZipFile(zipFilename);
Enumeration en = zipFile.getEntries();
ZipEntry zipEntry = null;
while (en.hasMoreElements()) {
zipEntry = (ZipEntry) en.nextElement();
if (zipEntry.isDirectory()) {
// mkdir directory
String dirName = zipEntry.getName();
// System.out.println("=dirName is:=" + dirName + "=end=");
dirName = dirName.substring(0, dirName.length() - 1);
File f = new File(outFile.getPath() + File.separator + dirName);
f.mkdirs();
} else {
// unzip file
String strFilePath = outFile.getPath() + File.separator
+ zipEntry.getName();
File f = new File(strFilePath);

// the codes remedified by can_do on 2010-07-02 =begin=
// /////begin/////
// 判断文件不存在的话，就创建该文件所在文件夹的目录
if (!f.exists()) {
String[] arrFolderName = zipEntry.getName().split("/");
String strRealFolder = "";
for (int i = 0; i < (arrFolderName.length - 1); i++) {
strRealFolder += arrFolderName[i] + File.separator;
}
strRealFolder = outFile.getPath() + File.separator
+ strRealFolder;
File tempDir = new File(strRealFolder);
// 此处使用.mkdirs()方法，而不能用.mkdir()
tempDir.mkdirs();
}
// /////end///
// the codes remedified by can_do on 2010-07-02 =end=
f.createNewFile();
InputStream in = zipFile.getInputStream(zipEntry);
FileOutputStream out = new FileOutputStream(f);
try {
int c;
byte[] by = new byte[BUFFEREDSIZE];
while ((c = in.read(by)) != -1) {
out.write(by, 0, c);
}
// out.flush();
} catch (IOException e) {
throw e;
} finally {
out.close();
in.close();
}
}
}
}

private static final int BUFFEREDSIZE = 1024;

public static void main(String[] args) {
CompressFile bean = new CompressFile();
try {
boolean isZip = false;
if (isZip) {
bean.zip("E:\\20100707", "d:/test_rar.zip");
} else {
bean.unzip("d:/test_rar.zip", "D:/temp");
}
} catch (IOException e) {
e.printStackTrace();
}
}

}