java 文件解压缩

直接上代码：

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import java.util.zip.ZipOutputStream;


/*
 * 对特定文件进行解压缩
 */
public class ZipAndUnZipUtil {
	
	private ZipAndUnZipUtil() {
	}

	private static ZipAndUnZipUtil zipSingleInstance;

	/*
	 * 生成实例
	 */
	public static ZipAndUnZipUtil getInstance() {
		if (null == zipSingleInstance) {
			zipSingleInstance= new ZipAndUnZipUtil();
		}
		return zipSingleInstance;
	}


	/*
	 * 解压文件
	 * @param srcPath 源压缩包路径
	 * @param despath 解压后存储的目录
	 * @return 解压后存储的路径目录
	 */
	@SuppressWarnings("unchecked")
	public  String unZip(String srcPath, String desPath) {
			if ("".equals(srcPath) || null == srcPath) {
				System.out.println("解压的文件的路径为空");
				return null;
			}
			if ("".equals(srcPath) || null == desPath) {
				System.out.println("文件解压后存储路径为");
				return null;
			}
			File srcFile = new File(srcPath);
			File desFile = new File(desPath);
		    //创建指定目录，如果其不存在的情况下
			if (!desFile.exists()) {
				if (!desFile.mkdirs()) {
					System.out.println("指定目录创建失败");
					return null;
				}
			}
			
			try {
				//读取zip文件
				ZipFile zipTest = new ZipFile(srcFile);
				Enumeration<ZipEntry> entries = (Enumeration<ZipEntry>) zipTest
						.entries();
				ZipEntry entry = null;
				while (entries.hasMoreElements()) {
					entry = entries.nextElement();
					if (entry.isDirectory()) {
						//创建目录
						File dirFile=new File(desPath+File.separator+entry.getName());
						dirFile.mkdirs();
						
					} else {
						//解压文件
						BufferedInputStream inputStream = new BufferedInputStream(zipTest.getInputStream(entry));
						BufferedOutputStream out =new BufferedOutputStream( new FileOutputStream(desPath+File.separator+entry.getName()));
	                    byte[] bytes=new byte[2*1024];
	                    int count;
	                    while((count=inputStream.read(bytes))!=-1){
	                    	out.write(bytes, 0, count);
	                    }
	                    inputStream.close();
	                    out.close();
					}
				}
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			
			return desPath;
	}

	/*
	 * 压缩文件
	 * 
	 * @param srcPath 需要压缩的文件路径 
	 * @param despath 压缩文件的存储目录
	 * @param name   文件名字
	 * @return desPath 压缩文件结果的存储路径，如果输入路径为空，或者存储路径已经存在，则返回null，
	 */
	public String zipDocuments(String srcPath, String desPath,String name) {
		if ("".equals(srcPath) || null == srcPath) {
			System.out.println("压缩的文件的路径为空");
			return null;
		}
		if ("".equals(srcPath) || null == desPath) {
			System.out.println("压缩文件的存储路径为");
			return null;
		}
		File srcFile = new File(srcPath);
		File desFile = new File(desPath);
		// 判断目标目录是否存在，如果不存在就创建
		if (!desFile.exists()) {
			if (!desFile.mkdirs()) {
				System.out.println("存储目录创建失败");
				return null;
			}

		}
		try {
			ZipOutputStream outZip = new ZipOutputStream(new FileOutputStream(
					desPath + File.separator + name));
			int start = srcPath.lastIndexOf(srcFile.getName());
			// 压缩文件
			zipDirAndFile(srcFile, outZip, start);
			outZip.close();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return desPath + File.separator + name;
	}

	/*
	 * 压缩文件及目录
	 */
	private void zipDirAndFile(File file, ZipOutputStream out, int start) {
		if (null == file | null == out) {
			throw new NullPointerException("文件或ZipOutputStream引用为空");
		}
		File[] files;
		// 如果file对象是目录
		if (file.isDirectory()) {
			files = file.listFiles();
			try {
				// 生成压缩目录文件
				String dirPath = file.getPath().substring(start);
				out.putNextEntry(new ZipEntry(absToreDirPath(dirPath)));
				out.closeEntry();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

			for (File f : files) {
				zipDirAndFile(f, out, start);
			}
		} else {
			// 如果file对象时文件
			BufferedInputStream inZip;
			byte[] buff;
			try {
				inZip = new BufferedInputStream(new FileInputStream(file));
				buff = new byte[5 * 1024];
         		ZipEntry zipEntry = new ZipEntry(new String(file.getPath()
						.substring(start)));
				out.putNextEntry(zipEntry);
				int count;
				while ((count = inZip.read(buff, 0, buff.length)) != -1) {
					out.write(buff, 0, count);
				}
				inZip.close();
				out.closeEntry();
			} catch (FileNotFoundException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}

	}

	/*
	 * 路径转换成相对路径 start:相对路径起始的位置
	 */
	private String absToreDirPath(String absPath) {
		char[] pathChars = absPath.toCharArray();
		for (int i = 0; i < pathChars.length; i++) {
			if (File.separatorChar == pathChars[i]) {
				pathChars[i] = '/';
			}
		}
		return new String(pathChars) + "/";
	}

}