Java基础之IO流，合并流对象SequenceInputStream对文件的切割与合并操作

文件的切割：

 

import java.io.*;

class SplitFilesDemo
{
    public static void main(String[] args) throws Exception
    {
        File file = new File("a.avi");
        
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream(file));
        FileOutputStream fos = null; 
        
        byte[] buffer = new byte[1024*1024*10];
        int length= 0,count = 1;
        
        while((length=bis.read(buffer))!=-1)
        {
            fos = new FileOutputStream("split\\"+count+++".part");
            fos.write(buffer,0,length);
            fos.close();
        }        
        
        bis.close();
    }
}

使用合并流对象SequenceInputStream对文件进行合并

 

import java.io.*;
import java.util.*;

class MergeFilesDemo
{
    public static void main(String[] args) throws Exception
    {
        List<FileInputStream> files = new ArrayList<FileInputStream>();
        getFiles(new File("split"),".part",files);
        
        final Iterator<FileInputStream> it = files.iterator();
        Enumeration<FileInputStream> em = new Enumeration<FileInputStream>(){
            public boolean hasMoreElements()
            {
                return it.hasNext();
            }
            
            public FileInputStream nextElement()
            {
                return it.next();
            }
        };
        
        SequenceInputStream sis = new SequenceInputStream(em);        
        FileOutputStream fos = new FileOutputStream(new File("b.avi"));
        
        int length = 0;
        byte[] buffer = new byte[1024*1024*10];
        while((length=sis.read(buffer))!=-1)
        {
            fos.write(buffer,0,length);
        }
        
        fos.close();
        sis.close();
    }
    
    public static void getFiles(File dir,String suffix,List<FileInputStream> listFiles) throws Exception
    {
        File[] files = dir.listFiles();
        for(File file : files)
        {
            if(file.isDirectory())
            {
                getFiles(file,suffix,listFiles);
            }
            else
            {
                if(file.getName().endsWith(suffix))
                    listFiles.add(new FileInputStream(file));
            }
        }
    }
}