java下io檔案切割合併功能

package cn.stat.p1.file;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.SequenceInputStream;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Enumeration;

public class qiefiledemo {

private static int SIZE=1024*1024;

    /**

     * @param args

     * @throws IOException

     */

    public static void main(String[] args) throws IOException {

        //檔案切割

        File file=new File("D:\\3.avi");

        splitFile(file);

        //檔案組合

        File file2=new File("D:\\cc");

        mergeFile(file2);

    }

    //檔案組合

    public static void mergeFile(File dir) throws IOException

    {

        ArrayList<FileInputStream> al=new ArrayList<FileInputStream>();

        for(int i=0;i<=19;i++)

        {

            al.add(new FileInputStream(new File(dir,i+".pat")));

        }

        Enumeration<FileInputStream> en=Collections.enumeration(al);

        SequenceInputStream sis=new SequenceInputStream(en);

        FileOutputStream fos=new FileOutputStream(new File(dir,"1.avi"));

        byte[] buf=new byte[SIZE];

        int len=0;

        while((len=sis.read(buf))!=-1)

        {

            fos.write(buf,0,len);

        }

        fos.close();

        sis.close();

    }

    //檔案切割

    public static void splitFile(File file) throws IOException

    {

        //用於讀取流的關聯檔案

        FileInputStream fis=new FileInputStream(file);

        //定義一個1M的緩衝區

        byte[] buf=new byte[SIZE];

        //建立目地

        FileOutputStream fos=null;

        int conun=0;

        int len=0;

        File dir=new File("D:\\cc");

        if(!dir.exists())

        {

            dir.mkdir();

        }

        while((len=fis.read(buf))!=-1)

        {

            fos=new FileOutputStream(new File(dir,(conun++)+".pat"));

            fos.write(buf,0,len);

        }

        fos.close();

        fis.close();

    }

}