java 实现jar包解压再压缩（亲测）

• 解压jar包
• 重新打包jar包
• 测试方法
• 删除jar包
• 遍历删除压缩文件

网上很多关于jar包处理的都不全面，而却很多根本无法使用，这是我经过试验得出的有效方法。同时，关于jar包无法file.delete()删除jar包，查找了很多文章都没具体实现，此文也实现了，jar包解压，再压缩流程，覆盖旧jar包，也算删除了，另外提供一种方式删除jar包，方法如下

 
    public static void extractJar(String destDir,String jarFile) {
    //    String jarFile = "E:/test/com.ide.core_1.0.0.jar";
       if((jarFile == null) || (jarFile.equals("")) || !jarFile.endsWith(".jar")) {
            return;
        }
        try {
            JarFile jar = new JarFile(jarFile);
            Enumeration enumeration = jar.entries();
            while(enumeration.hasMoreElements()) {
                JarEntry jarEntry = (JarEntry) enumeration.nextElement();
                String[] names = jarEntry.getName().split("/");
                for(int i = 0; i < names.length; i++) {
                    String path = destDir;
                    for(int j = 0; j < (i + 1); j++) {
                        path += File.separator + names[j];
                    }
                    File file = new File(path);
                    if(!file.exists()) {
                        if((i == (names.length - 1)) && !jarEntry.getName().endsWith("/")) {
                            file.createNewFile();
                        } else {
                            file.mkdirs();
                            continue;
                        }
                    } else {
                        continue;
                    }
                    InputStream is = jar.getInputStream(jarEntry);
                    FileOutputStream fos = new FileOutputStream(file);
                    while(is.available() > 0) {
                        fos.write(is.read());
                    }
                    fos.flush();
                    fos.close();
                }
            }

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

提供两种情况compressJar方法，直接指定需要压缩的文件夹，以及压缩路径；zipDirectory方法输入要解压文件的父文件，先遍历父文件下所有文件夹，再对文件夹压缩。

private static   List list =new ArrayList();


public  static  void  compressJar(String srcPath,String targetPath) {
    try {
        File file = new File(srcPath);
        //判断是否是目录
        if (file.isDirectory()) {
            if (list.size() > 0)
                list.clear();
            byte b[] = new byte[128];
            // 压缩文件的保存路径
            String zipFile = targetPath + File.separator + file.getName() + ".jar";
            // 压缩文件目录
          //  String filepath = file.getAbsolutePath() + File.separator;
            List fileList = allFile(srcPath+File.separator);

            FileOutputStream fileOutputStream = new FileOutputStream(zipFile);
            // 使用输出流检查
            CheckedOutputStream cs = new CheckedOutputStream(fileOutputStream, new CRC32());
            // 声明输出zip流
            ZipOutputStream out = new ZipOutputStream(new BufferedOutputStream(
                    cs));

            for (int i = 0; i < fileList.size(); i++) {
                InputStream in = new FileInputStream((String) fileList.get(i));
                String fileName = ((String) (fileList.get(i))).replace(File.separatorChar, '/');
           
                String tmp = file.getName() + "/";
                fileName = fileName.substring(fileName.lastIndexOf(tmp) + file.getName().length() + 1);
                ZipEntry e = new ZipEntry(fileName);
                out.putNextEntry(e);
                int len = 0;
                while ((len = in.read(b)) != -1) {
                    out.write(b, 0, len);
                }
                out.closeEntry();
            }
            out.close();
         
        }

    }
    catch (Exception e) {
        e.printStackTrace();
    }
}






public   static  void zipDirectory(String parentDirPath,String targetPath)
{
    try {
        File dirFile= new File(parentDirPath);
        File[] listArr = dirFile.listFiles();
        for (File childFile  : listArr) {
            if(childFile.isDirectory())
            {
                if(list.size()>0)
                    list.clear();
                byte b[] =  new  byte[128];
                // 压缩文件的保存路径
                String zipFile =targetPath+File.separator+childFile.getName()+".jar";

                // 压缩文件目录
                String filepath =childFile.getAbsolutePath()+File.separator;

                List fileList = allFile(filepath);

                FileOutputStream fileOutputStream =  new FileOutputStream(zipFile);
                // 使用输出流检查
                CheckedOutputStream cs =  new CheckedOutputStream(fileOutputStream,  new CRC32());
                // 声明输出zip流
                ZipOutputStream out =  new ZipOutputStream( new BufferedOutputStream(
                        cs));

                for ( int i = 0; i < fileList.size(); i++) {
                    InputStream in =  new FileInputStream((String)fileList.get(i));
                    String fileName = ((String)(fileList.get(i))).replace(File.separatorChar,'/');
             
                    String tmp= childFile.getName()+"/";
                    fileName = fileName.substring(fileName.lastIndexOf(tmp)+childFile.getName().length()+1);
                    ZipEntry e =  new ZipEntry(fileName);
                    out.putNextEntry(e);
                    int len = 0;
                    while((len = in.read(b)) != -1) {
                        out.write(b,0,len);
                    }
                    out.closeEntry();
                }
                out.close();
          
            }
        }

    }  catch (Exception e) {
        e.printStackTrace();
    }

}

private  static List allFile(String path)
{

    File file =  new File(path);
    String[] array =  null;
    String sTemp = "";


    if(file.isDirectory())
    {
    } else{
        return  null;
    }
    array= file.list();
    if(array.length>0)
    {
        for( int i=0;i 
测试方法 
public static void main(String[] args) throws Exception {
  String jarPath="E:\test\com.ide.platform_1.0.0\library.jar";
         String jarPath1="E:\test\com.ide.core_1.0.0.jar";
         String jarPath2="E:\test\com.ide.project.core_1.0.0.jar";
         String destDir=  jarPath.substring(0,jarPath.lastIndexOf(".jar"));
        String destDir1=   jarPath1.substring(0,jarPath1.lastIndexOf(".jar"));
        String destDir2=  jarPath2.substring(0,jarPath2.lastIndexOf(".jar"));
        extractJar(destDir,jarPath);
        extractJar(destDir1,jarPath1);
        extractJar(destDir2,jarPath2);
        //重新压缩
        compressJar(destDir,jarPath.substring(0,jarPath.lastIndexOf("\")));
  		compressJar(destDir1,jarPath1.substring(0,jarPath1.lastIndexOf("\")));
        compressJar(destDir2,jarPath1.substring(0,jarPath2.lastIndexOf("\")));
           }
 
删除jar包 
	jarsPath:需要删除的jar包；如：E:testcom.ide.project.core_1.0.0.jar
  Runtime.getRuntime().exec("cmd /c ping localhost -n 6 > nul && del "+jarsPath);
 
遍历删除压缩文件 
 public static void main(String[] args) throws Exception {
  File file = new File("E:\test\com.ide.core_1.0.0");
 deleteFile(file );
}
  public static void deleteFile(File file){
        if(file == null || !file.exists()){
            return;
        }
        //获得文件对象的子文件对象列表
        File[] files = file.listFiles();
        //遍历这些子文件
        for (File f : files){
            //判断这些子文件是否是目录
            if(f.isDirectory()){
                //是文件夹的话继续递归 如果是发现文件直接删除
                deleteFile(f);
            }else {
                f.delete();
            }
        }
        //删除空文件夹
        file.delete();
    }