Java 解压缩zip文件

不借助于其他的第三方组件，直接使用java提供的方法通过IO流操作zip文件。

 

代码如下:

package com.zip;

import java.io.File;
import java.io.BufferedOutputStream;
import java.io.BufferedInputStream;
import java.io.FileOutputStream;
import java.io.FileInputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;
/**
 * 该类实现文件夹压缩成zip文件和zip文件解压
 * @author Administrator
 *
 */
public class Zip{ 
    private ZipInputStream  zipIn;      //解压Zip 
    private ZipOutputStream zipOut;     //压缩Zip 
    private ZipEntry        zipEntry; 
    private static int      bufSize;    //size of bytes 
    private byte[]          buf; 
    private int             readedBytes; 
     
    public Zip(){ 
        this(512); 
    } 

    public Zip(int bufSize){ 
        this.bufSize = bufSize; 
        this.buf = new byte[this.bufSize]; 
    } 
     
    //压缩文件夹内的文件 
    public void doZip(String zipDirectory){//zipDirectoryPath:需要压缩的文件夹名 
        File file; 
        File zipDir; 

        zipDir = new File(zipDirectory); 
        String zipFileName = zipDirectory + ".zip";//压缩后生成的zip文件名 

        try{ 
            this.zipOut = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream(zipFileName))); 
            handleDir(zipDir , this.zipOut); 
            this.zipOut.close(); 
        }catch(Exception ioe){ 
            ioe.printStackTrace(); 
        } 
    } 

    //由doZip调用,递归完成目录文件读取
    private void handleDir(File dir , ZipOutputStream zipOut)throws Exception{ 
        FileInputStream fileIn; 
        File[] files; 

        files = dir.listFiles(); 
        if(files.length == 0){//如果目录为空,则单独创建之. 
            //ZipEntry的isDirectory()方法中,目录以"/"结尾. 
            this.zipOut.putNextEntry(new ZipEntry(dir.toString() + "/")); 
            this.zipOut.closeEntry(); 
        } 
        else{//如果目录不为空,则分别处理目录和文件. 
            for(File fileName : files){ 

                if(fileName.isDirectory()){ 
                    handleDir(fileName , this.zipOut); 
                } 
                else{ 
                    fileIn = new FileInputStream(fileName);
                    String name=dir.getName();
                    //生成的压缩包存放在原目录下
                    this.zipOut.putNextEntry(new ZipEntry(name+"/"+fileName.getName().toString()));
                    
                    //此方法存放在该项目目录下
                    //this.zipOut.putNextEntry(new ZipEntry(fileName.toString()));
                    while((this.readedBytes=fileIn.read(this.buf))>0){
                        this.zipOut.write(this.buf , 0 , this.readedBytes);
                    }
                    this.zipOut.closeEntry(); 
                } 
            } 
        } 
    } 

    //解压指定zip文件 
    public void unZip(String unZipfileName){//unZipfileName需要解压的zip文件名 
        FileOutputStream fileOut; 
        File file; 
        String f=unZipfileName.substring(0, unZipfileName.length()-4);
        File ff=new File(f);
        try{ 
            this.zipIn = new ZipInputStream (new 
            		BufferedInputStream(new FileInputStream(unZipfileName))); 
            while((this.zipEntry = this.zipIn.getNextEntry()) != null){ 
                file = new File(this.zipEntry.getName()); 
                if(this.zipEntry.isDirectory()){ 
                    file.mkdirs(); 
                } 
                else{ 
                    //如果指定文件的目录不存在,则创建之. 
                    File parent = file.getParentFile(); 
                    if(!parent.exists()){ 
                        parent.mkdirs(); 
                    } 
                    if(!ff.exists()){
                    	ff.mkdir();
                    }
                    fileOut = new FileOutputStream(f+"/"+file.getName()); 
                    
                    //fileOut = new FileOutputStream(file); 此方法存放到该项目目录下
                    while(( this.readedBytes = this.zipIn.read(this.buf) ) > 0){ 
                        fileOut.write(this.buf , 0 , this.readedBytes ); 
                    } 
                    fileOut.close(); 
                }
                
                this.zipIn.closeEntry();
            }
        }catch(Exception ioe){
            ioe.printStackTrace(); 
        }
    } 

    //设置缓冲区大小 
    public void setBufSize(int bufSize){ 
        this.bufSize = bufSize; 
    } 

    //测试Zip类 
    public static void main(String[] args)throws Exception{ 
        Zip zip=new Zip();
        zip.doZip("c:\\test");
        zip.unZip("c:\\test.zip");
    } 
} 



	
	
	

 

评论

1 楼 wzw3919 2015-11-24  

100行会报空指针