java解压缩.gz .zip .tar.gz等格式的压缩包方法总结

1、.gz文件是linux下常见的压缩格式。使用 java.util.zip.GZIPInputStream即可，压缩是 java.util.zip.GZIPOutputStream

     public static void unGzipFile(String sourcedir) {
         String ouputfile = "";
         try {
             //建立gzip压缩文件输入流
             FileInputStream fin = new FileInputStream(sourcedir);
             //建立gzip解压工作流
             GZIPInputStream gzin = new GZIPInputStream(fin);
             //建立解压文件输出流
             ouputfile = sourcedir.substring(0,sourcedir.lastIndexOf('.'));
             ouputfile = ouputfile.substring(0,ouputfile.lastIndexOf('.'));
             FileOutputStream fout = new FileOutputStream(ouputfile);   

             int num;
             byte[] buf=new byte[1024];

             while ((num = gzin.read(buf,0,buf.length)) != -1)
             {
                 fout.write(buf,0,num);
             }

             gzin.close();
             fout.close();
             fin.close();
         } catch (Exception ex){
             System.err.println(ex.toString());
         }
         return;
     }  

2、zip文件，使用java.util.zip.ZipEntry 和 java.util.zip.ZipFile

 /**
      * 解压缩zipFile
      * @param file 要解压的zip文件对象
      * @param outputDir 要解压到某个指定的目录下
      * @throws IOException
      */
     public static void unZip(File file,String outputDir) throws IOException {
         ZipFile zipFile = null;  

         try {
             Charset CP866 = Charset.forName("CP866");  //specifying alternative (non UTF-8) charset
             //ZipFile zipFile = new ZipFile(zipArchive, CP866);
             zipFile =  new ZipFile(file, CP866);
             createDirectory(outputDir,null);//创建输出目录  

             Enumeration<?> enums = zipFile.entries();
             while(enums.hasMoreElements()){  

                 ZipEntry entry = (ZipEntry) enums.nextElement();
                 System.out.println("解压." +  entry.getName());  

                 if(entry.isDirectory()){//是目录
                     createDirectory(outputDir,entry.getName());//创建空目录
                 }else{//是文件
                     File tmpFile = new File(outputDir + "/" + entry.getName());
                     createDirectory(tmpFile.getParent() + "/",null);//创建输出目录  

                     InputStream in = null;
                     OutputStream out = null;
                     try{
                         in = zipFile.getInputStream(entry);;
                         out = new FileOutputStream(tmpFile);
                         int length = 0;  

                         byte[] b = new byte[2048];
                         while((length = in.read(b)) != -1){
                             out.write(b, 0, length);
                         }  

                     }catch(IOException ex){
                         throw ex;
                     }finally{
                         if(in!=null)
                             in.close();
                         if(out!=null)
                             out.close();
                     }
                 }
             }  

         } catch (IOException e) {
             throw new IOException("解压缩文件出现异常",e);
         } finally{
             try{
                 if(zipFile != null){
                     zipFile.close();
                 }
             }catch(IOException ex){
                 throw new IOException("关闭zipFile出现异常",ex);
             }
         }
     }  

     /**
      * 构建目录
      * @param outputDir
      * @param subDir
      */
     public static void createDirectory(String outputDir,String subDir){
         File file = new File(outputDir);
         if(!(subDir == null || subDir.trim().equals(""))){//子目录不为空
             file = new File(outputDir + "/" + subDir);
         }
         if(!file.exists()){
               if(!file.getParentFile().exists())
                   file.getParentFile().mkdirs();
             file.mkdirs();
         }
     }  

3、.tar.gz文件可以看做先用tar打包，再使用gz进行压缩。

使用org.apache.tools.tar.TarEntry;  org.apache.tools.tar.TarInputStream 和 org.apache.tools.tar.TarOutputStream

  //------------------------------------------------------------------------------------------------------
     /**
      * 解压tar.gz 文件
      * @param file 要解压的tar.gz文件对象
      * @param outputDir 要解压到某个指定的目录下
      * @throws IOException
      */
     public static void unTarGz(File file,String outputDir) throws IOException{
         TarInputStream tarIn = null;
         try{
             tarIn = new TarInputStream(new GZIPInputStream(
                     new BufferedInputStream(new FileInputStream(file))),
                     1024 * 2);  

             createDirectory(outputDir,null);//创建输出目录  

             TarEntry entry = null;
             while( (entry = tarIn.getNextEntry()) != null ){  

                 if(entry.isDirectory()){//是目录
                     entry.getName();
                     createDirectory(outputDir,entry.getName());//创建空目录
                 }else{//是文件
                     File tmpFile = new File(outputDir + "/" + entry.getName());
                     createDirectory(tmpFile.getParent() + "/",null);//创建输出目录
                     OutputStream out = null;
                     try{
                         out = new FileOutputStream(tmpFile);
                         int length = 0;  

                         byte[] b = new byte[2048];  

                         while((length = tarIn.read(b)) != -1){
                             out.write(b, 0, length);
                         }  

                     }catch(IOException ex){
                         throw ex;
                     }finally{  

                         if(out!=null)
                             out.close();
                     }
                 }
             }
         }catch(IOException ex){
             throw new IOException("解压归档文件出现异常",ex);
         } finally{
             try{
                 if(tarIn != null){
                     tarIn.close();
                 }
             }catch(IOException ex){
                 throw new IOException("关闭tarFile出现异常",ex);
             }
         }
     }  

使用到的包头有：

 import java.io.BufferedInputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;

 import java.nio.charset.Charset;
 import java.util.Enumeration;
 import java.util.zip.GZIPInputStream;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;

 import org.apache.tools.tar.TarEntry;
 import org.apache.tools.tar.TarInputStream;
 import org.apache.tools.tar.TarOutputStream;