java实现多个文件压缩成压缩包

package util;

import java.io.bufferedinputstream;

import java.io.bufferedoutputstream;

import java.io.file;

import java.io.fileinputstream;

import java.io.fileoutputstream;

import java.io.inputstream;

import java.io.outputstream;

import java.util.arraylist;

import java.util.enumeration;

import java.util.list;

import java.util.zip.zipentry;

import java.util.zip.zipfile;

import java.util.zip.zipoutputstream;

public class ziptools {

   public static final string zip_filename = "" ; //需要解压缩的文件名

   public static final string zip_dir = "" ;  //需要压缩的文件夹

   public static final string un_zip_dir = "" ;  //要解压的文件目录

   public static final int buffer = 1024 ;  //缓存大小

public static void zipfile(string basedir,string filename) throws exception{

     list filelist=getsubfiles( new file(basedir));

     zipoutputstream zos= new zipoutputstream( new fileoutputstream(filename));

     zipentry ze= null ;

     byte [] buf= new byte [buffer];

     int readlen= 0 ;

     for ( int i = 0 ; i <filelist.size(); i++) {

       file f=(file)filelist.get(i);

       ze= new zipentry(getabsfilename(basedir, f));

       ze.setsize(f.length());

       ze.settime(f.lastmodified());  

       zos.putnextentry(ze);

       inputstream is= new bufferedinputstream( new fileinputstream(f));

       while ((readlen=is.read(buf, 0 , buffer))!=- 1 ) {

         zos.write(buf, 0 , readlen);

       }

       is.close();

     }

     zos.close();

   }

private static string getabsfilename(string basedir, file realfilename){

     file real=realfilename;

     file base= new file(basedir);

     string ret=real.getname();

     while ( true ) {

       real=real.getparentfile();

       if (real== null ) 

         break ;

       if (real.equals(base)) 

         break ;

       else

         ret=real.getname()+ "/" +ret;

     }

     return ret;

   }

private static list getsubfiles(file basedir){

     list ret= new arraylist();

     file[] tmp=basedir.listfiles();

     for ( int i = 0 ; i <tmp.length; i++) {

       if (tmp[i].isfile())

         ret.add(tmp[i]);

       if (tmp[i].isdirectory())

         ret.addall(getsubfiles(tmp[i]));

     }

     return ret;

   }

public static void upzipfile() throws exception{

     zipfile zfile= new zipfile(zip_filename);

     enumeration zlist=zfile.entries();

     zipentry ze= null ;

     byte [] buf= new byte [ 1024 ];

     while (zlist.hasmoreelements()){

       ze=(zipentry)zlist.nextelement();    

       if (ze.isdirectory()){

         file f= new file(zip_dir+ze.getname());

         f.mkdir();

         continue ;

       }

       outputstream os= new bufferedoutputstream( new fileoutputstream(getrealfilename(zip_dir, ze.getname())));

       inputstream is= new bufferedinputstream(zfile.getinputstream(ze));

       int readlen= 0 ;

       while ((readlen=is.read(buf, 0 , 1024 ))!=- 1 ) {

         os.write(buf, 0 , readlen);

       }

       is.close();

       os.close(); 

     }

     zfile.close();

   }

public static file getrealfilename(string basedir, string absfilename){

     string[] dirs=absfilename.split( "/" );

     file ret= new file(basedir);

     if (dirs.length> 1 ){

       for ( int i = 0 ; i < dirs.length- 1 ;i++) {

         ret= new file(ret, dirs[i]);

       }

       if (!ret.exists())

         ret.mkdirs();

       ret= new file(ret, dirs[dirs.length- 1 ]);

       return ret;

     }

     return ret;

   }

public static void deletedirfile(string path){

    file file= new file(path);

    if (file.isdirectory()){    //如果是目录，先递归删除

      string[] list=file.list();

      for ( int i= 0 ;i<list.length;i++){

      deletedirfile(path+ "\\" +list[i]); //先删除目录下的文件

      }

    }   

    file.delete();

  }

public static string newfolder(string dir){

  java.io.file myfilepath= new java.io.file(dir);

  if (myfilepath.isdirectory()){} else {

   myfilepath.mkdirs();

  }

  return dir;

  }

public static string getfilenames(string path){ 

     file file = new file(path);      // get file list where the path has

     file[] array = file.listfiles();     // 获得文件列表

     string pdfnames= "" ;

     for ( int i= 0 ;i<array.length;i++){ 

       if (array[i].isfile()){ 

         if (array[i].getname().endswith( ".pdf" )){  //获得pdf文件名称

          pdfnames+=array[i].getname().substring( 0 ,array[i].getname().length()- 4 )+ "," ;

         }

       }

     }

     if (pdfnames.length()> 0 ){

      pdfnames.substring( 0 ,pdfnames.length()- 1 );

     }

     return pdfnames;

   }

public static void copyfile(string oldpath, string newpath) {

     try {

       int bytesum = 0 ;

       int byteread = 0 ;

       file oldfile = new file(oldpath);

       if (oldfile.exists()) {     //文件存在时

         inputstream instream = new fileinputstream(oldpath); //读入原文件

         fileoutputstream fs = new fileoutputstream(newpath);

         byte [] buffer = new byte [ 1444 ];

         while ( (byteread = instream.read(buffer)) != - 1 ) {

           bytesum += byteread;    //字节数文件大小

           fs.write(buffer, 0 , byteread);

         }

         instream.close();

       }

     }

     catch (exception e) {

       system.out.println( "copy file error!" );

       e.printstacktrace();

     }

   }

public static boolean fileexist(string filenames,string pdfname){

  boolean flag= false ;

  if (! "" .equals(filenames)){

   string[] namearr=filenames.split( "," );

   for ( int i= 0 ;i<namearr.length;i++){

   if (pdfname.equals(namearr[i])){    //如果文件名相同则执行拷贝操作(拷贝到zip目录准备打包)

    flag= true ;

    break ;

   }

   }

  }

  return flag;

  }

public static void deletefileanddir(string path){

   file file = new file(path); 

      file[] array = file.listfiles();

      for ( int i= 0 ;i<array.length;i++){ 

        if (array[i].isfile()){

          array[i].delete();

        } else if (array[i].isdirectory()){ 

        deletedirfile(array[i].getpath());

        } 

      } 

  }

}