java 文件压缩和解压（ZipInputStream， ZipOutputStream）

　　最近在看java se 的IO 部分 ， 看到 java 的文件的压缩和解压比较有意思，主要用到了两个IO流-ZipInputStream， ZipOutputStream，不仅可以对文件进行压缩，还可以对文件夹进行压缩和解压。

　　ZipInputStream位于java.util.zip包下。下面是它的API，比较简单。

ZipOutputStream位于java.util.zip包下。下面是它的API，比较简单。

文件的压缩

 public class TestFile
 {
     public static void main ( String [ ] args ) throws IOException
     {
         // new a file input stream
         FileInputStream fis = new FileInputStream (
                 "/home/liangruihua/ziptest/1.txt" ) ;
         BufferedInputStream bis = new BufferedInputStream ( fis ) ;

         // new a zipPutputStream
         // /home/liangruihua/ziptest/1.zip -- the out put file path and
         // name
         ZipOutputStream zos = new ZipOutputStream (
                 new FileOutputStream (
                         "/home/liangruihua/ziptest/1.zip" ) ) ;
         BufferedOutputStream bos = new BufferedOutputStream ( zos ) ;

         // set the file name in the .zip file
         zos.putNextEntry ( new ZipEntry ( "1.txt" ) ) ;

         // set the declear
         zos.setComment ( "by liangruihua test!" ) ;

         byte [ ] b = new byte [ 100 ] ;
         while ( true )
         {
             int len = bis.read ( b ) ;
             if ( len == - 1 )
                 break ;
             bos.write ( b , 0 , len ) ;
         }
         fis.close ( ) ;
         zos.close ( ) ;
     }
 }

文件夹的压缩

 public class TestDir
 {
     public static void main ( String [ ] args ) throws IOException
     {
         // the file path need to compress
         File file = new File ( "/home/liangruihua/ziptest/test" ) ;
         ZipOutputStream zos = new ZipOutputStream (
                 new FileOutputStream (
                         "/home/liangruihua/ziptest/test.zip" ) ) ;

         // judge the file is the directory
         if ( file.isDirectory ( ) )
         {
             // get the every file in the directory
             File [ ] files = file.listFiles ( ) ;

             for ( int i = 0 ; i < files.length ; i ++ )
             {
                 // new the BuuferedInputStream
                 BufferedInputStream bis = new BufferedInputStream (
                         new FileInputStream (
                                 files [ i ] ) ) ;
                 // the file entry ,set the file name in the zip
                 // file
                 zos.putNextEntry ( new ZipEntry ( file
                         .getName ( )
                         + file.separator
                         + files [ i ].getName ( ) ) ) ;
                 while ( true )
                 {
                     byte [ ] b = new byte [ 100 ] ;
                     int len = bis.read ( b ) ;
                     if ( len == - 1 )
                         break ;
                     zos.write ( b , 0 , len ) ;
                 }

                 // close the input stream
                 bis.close ( ) ;
             }

         }
         // close the zip output stream
         zos.close ( ) ;
     }
 }

文件的解压

 public class TestZipInputStream
 {
     public static void main ( String [ ] args ) throws ZipException ,
             IOException
     {
         // get a zip file instance
         File file = new File ( "/home/liangruihua/ziptest/test.zip" ) ;

         // get a ZipFile instance
         ZipFile zipFile = new ZipFile ( file ) ;

         // create a ZipInputStream instance
         ZipInputStream zis = new ZipInputStream ( new FileInputStream (
                 file ) ) ;

         // create a ZipEntry instance , lay the every file from
         // decompress file temporarily
         ZipEntry entry = null ;

         // a circle to get every file
         while ( ( entry = zis.getNextEntry ( ) ) != null )
         {
             System.out.println ( "decompress file :"
                     + entry.getName ( ) ) ;

             // define the path to set the file
             File outFile = new File ( "/home/liangruihua/ziptest/"
                     + entry.getName ( ) ) ;

             // if the file's parent directory wasn't exits ,than
             // create the directory
             if ( ! outFile.getParentFile ( ).exists ( ) )
             {
                 outFile.getParentFile ( ).mkdir ( ) ;
             }

             // if the file not exits ,than create the file
             if ( ! outFile.exists ( ) )
             {
                 outFile.createNewFile ( ) ;
             }

             // create an input stream
             BufferedInputStream bis = new BufferedInputStream (
                     zipFile.getInputStream ( entry ) ) ;

             // create an output stream
             BufferedOutputStream bos = new BufferedOutputStream (
                     new FileOutputStream ( outFile ) ) ;
             byte [ ] b = new byte [ 100 ] ;
             while ( true )
             {
                 int len = bis.read ( b ) ;
                 if ( len == - 1 )
                     break ;
                 bos.write ( b , 0 , len ) ;
             }
             // close stream
             bis.close ( ) ;
             bos.close ( ) ;
         }
         zis.close ( ) ;

     }
 }