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  由于网络传输存在着传输速度,传输路径等问题,将一个文件分为若干块来传送,可以提高传输效率,JAVA多线程技术正是将一个任务分为若干个任务来同时完成.        该实例应用JAVA多线程技术,将一个网络文件分为若干块,每一个线程负责一块数据的下载,下载完毕后将其保存在指定的磁盘路径中.         首先创建继承Thread类的传输文件线程类,其JAVA文件名为SiteFileFetch.java,代码如下: view plaincopy to clipboardprint?
import java.io.*;  
 
import java.net.*;  
 
 
 
public class SiteFileFetch extends Thread {     //传输文件线程类  
 
    SiteInfoBean siteInfoBean=null;                 //创建文件信息实例  
 
    long [] nPos;                                   //文件位置指针  
 
    long [] nStartPos;                              //开始位置  
 
    long [] nEndPos;                                //结束位置  
 
    FileSplitterFetch [] fileSplitterFetch;         //子线程对象  
 
    long nFileLength;                               //文件长度  
 
    boolean bFirst=true;                            //是否第一次读取  
 
    boolean bStop=false;                            //停止标志  
 
    File tmpFile;                                   //文件传输临时信息  
 
    DataOutputStream output;                        //输出到文件的输出流  
 
    public SiteFileFetch(SiteInfoBean bean) throws IOException{  
 
        siteInfoBean=bean;  
 
        tmpFile= new File(bean.getSFilePath()+File.separator+bean.getSFileName()+".info");  
 
        if(tmpFile.exists()){  
 
            bFirst=false;  
 
            read_nPos();  
 
        }  
 
        else{  
 
            nStartPos=new long[bean.getNSplitter()];  
 
            nEndPos=new long[bean.getNSplitter()];  
 
        }  
 
    }  
 
    public void run(){  
 
        try{  
 
            if(bFirst){  
 
                nFileLength=getFileSize();              //获得文件长度  
 
                if(nFileLength==-1){  
 
                    System.err.println("File Length is not known");  
 
                }  
 
                else   
 
                    if(nFileLength==-2){  
 
                        System.err.println("File is not access!");  
 
                    }  
 
                    else{  
 
                        for(int i=0;i<nStartPos.length;i++){         //分割下载文件  
 
                            nStartPos[i]=(long)(i*(nFileLength/nStartPos.length));  
 
                        }  
 
                        for(int i=0;i<nEndPos.length-1;i++){  
 
                            nEndPos[i]=nStartPos[i+1];  
 
                        }  
 
                        nEndPos[nEndPos.length-1]=nFileLength;  
 
                    }  
 
            }  
 
            fileSplitterFetch=new FileSplitterFetch[nStartPos.length];              //创建FileSplitterFetch类实例  
 
            for(int i=0;i<nStartPos.length;i++){                 //启动FileSplitterFetch线程  
 
                fileSplitterFetch[i]=new FileSplitterFetch(siteInfoBean.getSSiteURL(),siteInfoBean.getSFilePath()+File.separator+siteInfoBean.getSFileName(),nStartPos[i],nEndPos[i],i);  
 
                Utility.log("Thread "+i+",nStartPos="+nStartPos[i]+" ,nEndPos= "+nEndPos[i]);  
 
                fileSplitterFetch[i].start();  
 
            }  
 
            boolean breakWhile=false;  
 
            while(!bStop){                  //等待子线程结束  
 
                write_nPos();  
 
                Utility.sleep(500);  
 
                breakWhile=true;  
 
                for(int i=0;i<nStartPos.length;i++){  
 
                    if(!fileSplitterFetch[i].bDownOver){            //等待子线程返回  
 
                        breakWhile=false;  
 
                        break;  
 
                    }  
 
                }  
 
                if(breakWhile)              //是否结束while循环  
 
                    break;  
 
            }  
 
            System.out.println("文件传输结束!");  
 
        }  
 
        catch(Exception e){  
 
            e.printStackTrace();  
 
        }  
 
    }  
 
      
 
    public long getFileSize(){              //获得文件长度  
 
        int nFileLength=-1;  
 
        try{                //创建与WEB服务器的连接  
 
            URL url=new URL(siteInfoBean.getSSiteURL());  
 
            HttpURLConnection httpConnection=(HttpURLConnection)url.openConnection();  
 
            httpConnection.setRequestProperty("User-Agent", "NetFox");  
 
            int responseCode=httpConnection.getResponseCode();  
 
            if(responseCode>=400){  
 
                processErrorCode(responseCode);  
 
                return -2;              //-2为WEB服务器响应错误  
 
            }  
 
            String sHeader;  
 
            for(int i=1;;i++){  
 
                sHeader=httpConnection.getHeaderFieldKey(i);  
 
                if(sHeader!=null){  
 
                    if(sHeader.equals("Content-Length")){  
 
                        nFileLength=Integer.parseInt(httpConnection.getHeaderField(sHeader));  
 
                        break;  
 
                    }  
 
                }  
 
                else 
 
                    break;  
 
            }  
 
        }  
 
        catch(IOException e){  
 
            e.printStackTrace();  
 
        }  
 
        catch(Exception e){  
 
            e.printStackTrace();  
 
        }  
 
        Utility.log(nFileLength);  
 
        return nFileLength;  
 
    }  
 
      
 
    private void write_nPos(){                  //保存传输文件指针位置  
 
        try{  
 
            output=new DataOutputStream(new FileOutputStream(tmpFile));  
 
            output.writeInt(nStartPos.length);  
 
            for(int i=0;i<nStartPos.length;i++){  
 
                output.writeLong(fileSplitterFetch[i].nStartPos);  
 
                output.writeLong(fileSplitterFetch[i].nEndPos);  
 
            }  
 
            output.close();  
 
        }  
 
        catch(IOException e){e.printStackTrace();}  
 
        catch(Exception e) {e.printStackTrace();}  
 
    }  
 
      
 
    private void read_nPos(){               //读取保存的下载文件指针位置  
 
        try{  
 
            DataInputStream input=new DataInputStream(new FileInputStream(tmpFile));  
 
            int nCount=input.readInt();  
 
            nStartPos=new long[nCount];  
 
            nEndPos=new long[nCount];  
 
            for(int i=0;i<nStartPos.length;i++){  
 
                nStartPos[i]=input.readLong();  
 
                nEndPos[i]=input.readLong();  
 
            }  
 
            input.close();  
 
        }  
 
        catch(IOException e){e.printStackTrace();}  
 
        catch(Exception e) {e.printStackTrace();}  
 
    }  
 
      
 
    private void processErrorCode(int nErrorCode){  
 
        System.err.println("Error Code: "+nErrorCode);  
 
    }  
 
      
 
    public  void siteStop(){  
 
        bStop=true;  
 
        for(int i=0;i<nStartPos.length;i++)  
 
            fileSplitterFetch[i].splitterStop();  
 
    }  
 

import java.io.*;

import java.net.*;

 

public class SiteFileFetch extends Thread {  //传输文件线程类

 SiteInfoBean siteInfoBean=null;     //创建文件信息实例

 long [] nPos;         //文件位置指针

 long [] nStartPos;        //开始位置

 long [] nEndPos;        //结束位置

 FileSplitterFetch [] fileSplitterFetch;   //子线程对象

 long nFileLength;        //文件长度

 boolean bFirst=true;       //是否第一次读取

 boolean bStop=false;       //停止标志

 File tmpFile;         //文件传输临时信息

 DataOutputStream output;      //输出到文件的输出流

 public SiteFileFetch(SiteInfoBean bean) throws IOException{

  siteInfoBean=bean;

  tmpFile= new File(bean.getSFilePath()+File.separator+bean.getSFileName()+".info");

  if(tmpFile.exists()){

   bFirst=false;

   read_nPos();

  }

  else{

   nStartPos=new long[bean.getNSplitter()];

   nEndPos=new long[bean.getNSplitter()];

  }

 }

 public void run(){

  try{

   if(bFirst){

    nFileLength=getFileSize();    //获得文件长度

    if(nFileLength==-1){

     System.err.println("File Length is not known");

    }

    else

     if(nFileLength==-2){

      System.err.println("File is not access!");

     }

     else{

      for(int i=0;i<nStartPos.length;i++){   //分割下载文件

       nStartPos[i]=(long)(i*(nFileLength/nStartPos.length));

      }

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

       nEndPos[i]=nStartPos[i+1];

      }

      nEndPos[nEndPos.length-1]=nFileLength;

     }

   }

   fileSplitterFetch=new FileSplitterFetch[nStartPos.length];    //创建FileSplitterFetch类实例

   for(int i=0;i<nStartPos.length;i++){     //启动FileSplitterFetch线程

    fileSplitterFetch[i]=new FileSplitterFetch(siteInfoBean.getSSiteURL(),siteInfoBean.getSFilePath()+File.separator+siteInfoBean.getSFileName(),nStartPos[i],nEndPos[i],i);

    Utility.log("Thread "+i+",nStartPos="+nStartPos[i]+" ,nEndPos= "+nEndPos[i]);

    fileSplitterFetch[i].start();

   }

   boolean breakWhile=false;

   while(!bStop){     //等待子线程结束

    write_nPos();

    Utility.sleep(500);

    breakWhile=true;

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

     if(!fileSplitterFetch[i].bDownOver){   //等待子线程返回

      breakWhile=false;

      break;

     }

    }

    if(breakWhile)    //是否结束while循环

     break;

   }

   System.out.println("文件传输结束!");

  }

  catch(Exception e){

   e.printStackTrace();

  }

 }

 

 public long getFileSize(){    //获得文件长度

  int nFileLength=-1;

  try{    //创建与WEB服务器的连接

   URL url=new URL(siteInfoBean.getSSiteURL());

   HttpURLConnection httpConnection=(HttpURLConnection)url.openConnection();

   httpConnection.setRequestProperty("User-Agent", "NetFox");

   int responseCode=httpConnection.getResponseCode();

   if(responseCode>=400){

    processErrorCode(responseCode);

    return -2;    //-2为WEB服务器响应错误

   }

   String sHeader;

   for(int i=1;;i++){

    sHeader=httpConnection.getHeaderFieldKey(i);

    if(sHeader!=null){

     if(sHeader.equals("Content-Length")){

      nFileLength=Integer.parseInt(httpConnection.getHeaderField(sHeader));

      break;

     }

    }

    else

     break;

   }

  }

  catch(IOException e){

   e.printStackTrace();

  }

  catch(Exception e){

   e.printStackTrace();

  }

  Utility.log(nFileLength);

  return nFileLength;

 }

 

 private void write_nPos(){     //保存传输文件指针位置

  try{

   output=new DataOutputStream(new FileOutputStream(tmpFile));

   output.writeInt(nStartPos.length);

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

    output.writeLong(fileSplitterFetch[i].nStartPos);

    output.writeLong(fileSplitterFetch[i].nEndPos);

   }

   output.close();

  }

  catch(IOException e){e.printStackTrace();}

  catch(Exception e) {e.printStackTrace();}

 }

 

 private void read_nPos(){    //读取保存的下载文件指针位置

  try{

   DataInputStream input=new DataInputStream(new FileInputStream(tmpFile));

   int nCount=input.readInt();

   nStartPos=new long[nCount];

   nEndPos=new long[nCount];

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

    nStartPos[i]=input.readLong();

    nEndPos[i]=input.readLong();

   }

   input.close();

  }

  catch(IOException e){e.printStackTrace();}

  catch(Exception e) {e.printStackTrace();}

 }

 

 private void processErrorCode(int nErrorCode){

  System.err.println("Error Code: "+nErrorCode);

 }

 

 public  void siteStop(){

  bStop=true;

  for(int i=0;i<nStartPos.length;i++)

   fileSplitterFetch[i].splitterStop();

 }

}创建继承Thread类的将要传输的网络文件分割线程类,文件名为FileSplitterFetch.java view plaincopy to clipboardprint?
import java.io.*;  
 
import java.net.*;  
 
 
 
public class FileSplitterFetch extends Thread {  
 
    String sURL;                                //定义文件传输时使用的变量  
 
    long nStartPos;                             //分段文件传输开始位置  
 
    long nEndPos;                               //分段文件传输结束位置  
 
    int nThreadID;                              //子线程ID  
 
    boolean bDownOver=false;                    //完成文件传输  
 
    boolean bStop=false;                        //停止文件传输  
 
    FileAccess fileAccess=null;                   
 
      
 
    public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException{  
 
        this.sURL=sURL;  
 
        this.nStartPos=nStart;  
 
        this.nEndPos=nEnd;  
 
        nThreadID=id;  
 
        fileAccess=new FileAccess(sName,nStartPos);         //创建文件并打开  
 
    }  
 
      
 
    public void run(){  
 
        while(nStartPos<nEndPos && !bStop){  
 
            try{                                    //创建连接  
 
                URL url=new URL(sURL);  
 
                HttpURLConnection httpConnection=(HttpURLConnection)url.openConnection();  
 
                httpConnection.setRequestProperty("User-Agent", "NextFox");  
 
                String sProperty="bytes= "+nStartPos+"-";  
 
                httpConnection.setRequestProperty("RANGE", sProperty);  
 
                Utility.log(sProperty);  
 
                InputStream input=httpConnection.getInputStream();          //创建输入流对象  
 
                byte[] b=new byte[1024];  
 
                int nRead;  
 
                while((nRead=input.read(b,0,1024))>0 && nStartPos<nEndPos && !bStop){  
 
                    nStartPos+=fileAccess.write(b,0,nRead);  
 
                }  
 
                Utility.log("Thread "+nThreadID + "is over!");  
 
                bDownOver=true;  
 
            }  
 
            catch(Exception e){  
 
                e.printStackTrace();  
 
            }  
 
        }  
 
          
 
          
 
    }  
 
      
 
    public void logResponseHead(HttpURLConnection con){         //处理和响应服务器头数据  
 
        for(int i=1;;i++){  
 
            String header=con.getHeaderFieldKey(i);  
 
            if(header!=null)  
 
                Utility.log(header+" : "+con.getHeaderField(header));  
 
            else   
 
                break;  
 
        }  
 
    }  
 
      
 
    public void splitterStop(){  
 
        bStop=true;  
 
    }  
 

import java.io.*;

import java.net.*;

 

public class FileSplitterFetch extends Thread {

 String sURL;        //定义文件传输时使用的变量

 long nStartPos;        //分段文件传输开始位置

 long nEndPos;        //分段文件传输结束位置

 int nThreadID;        //子线程ID

 boolean bDownOver=false;     //完成文件传输

 boolean bStop=false;      //停止文件传输

 FileAccess fileAccess=null;     

 

 public FileSplitterFetch(String sURL,String sName,long nStart,long nEnd,int id) throws IOException{

  this.sURL=sURL;

  this.nStartPos=nStart;

  this.nEndPos=nEnd;

  nThreadID=id;

  fileAccess=new FileAccess(sName,nStartPos);   //创建文件并打开

 }

 

 public void run(){

  while(nStartPos<nEndPos && !bStop){

   try{         //创建连接

    URL url=new URL(sURL);

    HttpURLConnection httpConnection=(HttpURLConnection)url.openConnection();

    httpConnection.setRequestProperty("User-Agent", "NextFox");

    String sProperty="bytes= "+nStartPos+"-";

    httpConnection.setRequestProperty("RANGE", sProperty);

    Utility.log(sProperty);

    InputStream input=httpConnection.getInputStream();   //创建输入流对象

    byte[] b=new byte[1024];

    int nRead;

    while((nRead=input.read(b,0,1024))>0 && nStartPos<nEndPos && !bStop){

     nStartPos+=fileAccess.write(b,0,nRead);

    }

    Utility.log("Thread "+nThreadID + "is over!");

    bDownOver=true;

   }

   catch(Exception e){

    e.printStackTrace();

   }

  }

  

  

 }

 

 public void logResponseHead(HttpURLConnection con){   //处理和响应服务器头数据

  for(int i=1;;i++){

   String header=con.getHeaderFieldKey(i);

   if(header!=null)

    Utility.log(header+" : "+con.getHeaderField(header));

   else

    break;

  }

 }

 

 public void splitterStop(){

  bStop=true;

 }

}创建设置和获取网络信息类,类名为SiteInfoBean.java view plaincopy to clipboardprint?
public class SiteInfoBean {         //定义获取和设置相关文件类信息  
 
    private String sSiteURL;            //定义URL变量  
 
    private String sFilePath;           //定义存文件路径变量  
 
    private String sFileName;           //定义文件名变量  
 
    private int nSplitter;              //定义传输文件计数器  
 
      
 
    public SiteInfoBean(){  
 
        this("","","",5);  
 
    }  
 
      
 
    public SiteInfoBean(String sURL,String sPath,String sName,int nSplitter){  
 
        sSiteURL=sURL;  
 
        sFilePath=sPath;  
 
        sFileName=sName;  
 
        this.nSplitter=nSplitter;  
 
    }  
 
      
 
    public String getSSiteURL(){  
 
        return sSiteURL;  
 
    }  
 
      
 
    public void setSSiteURL(String value){  
 
        sSiteURL=value;  
 
    }  
 
      
 
    public String getSFilePath(){  
 
        return sFilePath;  
 
    }  
 
      
 
    public void setSFilePath(String value){  
 
        sFilePath=value;  
 
    }  
 
      
 
    public String getSFileName(){  
 
        return sFileName;  
 
    }  
 
      
 
    public void setSFileName(String value){  
 
        sFileName=value;  
 
    }  
 
      
 
    public int getNSplitter(){  
 
        return nSplitter;  
 
    }  
 
      
 
    public void setNSplitter(int nCount){  
 
        nSplitter=nCount;  
 
    }  
 

public class SiteInfoBean {   //定义获取和设置相关文件类信息

 private String sSiteURL;   //定义URL变量

 private String sFilePath;   //定义存文件路径变量

 private String sFileName;   //定义文件名变量

 private int nSplitter;    //定义传输文件计数器

 

 public SiteInfoBean(){

  this("","","",5);

 }

 

 public SiteInfoBean(String sURL,String sPath,String sName,int nSplitter){

  sSiteURL=sURL;

  sFilePath=sPath;

  sFileName=sName;

  this.nSplitter=nSplitter;

 }

 

 public String getSSiteURL(){

  return sSiteURL;

 }

 

 public void setSSiteURL(String value){

  sSiteURL=value;

 }

 

 public String getSFilePath(){

  return sFilePath;

 }

 

 public void setSFilePath(String value){

  sFilePath=value;

 }

 

 public String getSFileName(){

  return sFileName;

 }

 

 public void setSFileName(String value){

  sFileName=value;

 }

 

 public int getNSplitter(){

  return nSplitter;

 }

 

 public void setNSplitter(int nCount){

  nSplitter=nCount;

 }

}创建保存获取的网络文件类,类名为FileAccess.java view plaincopy to clipboardprint?
import java.io.*;  
 
 
 
 
 
public class FileAccess implements Serializable {       //定义文件访问类  
 
    RandomAccessFile oSavedFile;  
 
    long nPos;  
 
      
 
    public FileAccess() throws IOException{  
 
        this("",0);  
 
    }  
 
      
 
    public FileAccess(String sName,long nPos) throws IOException{  
 
        oSavedFile=new RandomAccessFile(sName,"rw");  
 
        this.nPos=nPos;  
 
        oSavedFile.seek(nPos);  
 
    }  
 
      
 
    public synchronized int write(byte[] b,int nStart,int nLen){  
 
        int n=-1;  
 
        try{  
 
            oSavedFile.write(b,nStart,nLen);  
 
            n=nLen;  
 
        }  
 
        catch(IOException e){  
 
            e.printStackTrace();  
 
        }  
 
        return n;  
 
    }  
 

import java.io.*;

 

 

public class FileAccess implements Serializable {  //定义文件访问类

 RandomAccessFile oSavedFile;

 long nPos;

 

 public FileAccess() throws IOException{

  this("",0);

 }

 

 public FileAccess(String sName,long nPos) throws IOException{

  oSavedFile=new RandomAccessFile(sName,"rw");

  this.nPos=nPos;

  oSavedFile.seek(nPos);

 }

 

 public synchronized int write(byte[] b,int nStart,int nLen){

  int n=-1;

  try{

   oSavedFile.write(b,nStart,nLen);

   n=nLen;

  }

  catch(IOException e){

   e.printStackTrace();

  }

  return n;

 }

}创建在下载过程中应用的工具类,名为Utility.java view plaincopy to clipboardprint?
public class Utility {              //定义输出提示信息及线程sleep类  
 
    public Utility(){  
 
          
 
    }  
 
      
 
    public static void sleep(int nSecond){  
 
        try{  
 
            Thread.sleep(nSecond);  
 
        }  
 
        catch(Exception e){  
 
            e.printStackTrace();  
 
        }  
 
    }  
 
      
 
    public static void log(String sMsg){  
 
        System.out.println(sMsg);  
 
    }  
 
      
 
    public static void log(int sMsg){  
 
        System.out.println(sMsg);  
 
    }  
 

public class Utility {    //定义输出提示信息及线程sleep类

 public Utility(){

  

 }

 

 public static void sleep(int nSecond){

  try{

   Thread.sleep(nSecond);

  }

  catch(Exception e){

   e.printStackTrace();

  }

 }

 

 public static void log(String sMsg){

  System.out.println(sMsg);

 }

 

 public static void log(int sMsg){

  System.out.println(sMsg);

 }

}

创建包含main()方法的测试类,文件名为TestMethod.java view plaincopy to clipboardprint?
public class TestMethod {  
 
    private String sWebAddr="http://localhost:8080/java.zip";           //定义WEB地址和文件名  
 
    private String sSavePath="d:\\temp";                                //定义存文件路径  
 
    private String sSaveName="java.zip";                                //定义文件名  
 
    public TestMethod(){  
 
        try{  
 
            SiteInfoBean bean=new SiteInfoBean(sWebAddr,sSavePath,sSaveName,5);  
 
            SiteFileFetch fileFetch=new SiteFileFetch(bean);  
 
            fileFetch.start();  
 
        }  
 
        catch(Exception e){  
 
            e.printStackTrace();  
 
        }  
 
    }  
 
      
 
    public static void main(String[] args){  
 
        new TestMethod();  
 
    }  
 

public class TestMethod {

 private String sWebAddr="http://localhost:8080/java.zip";   //定义WEB地址和文件名

 private String sSavePath="d:\\temp";        //定义存文件路径

 private String sSaveName="java.zip";        //定义文件名

 public TestMethod(){

  try{

   SiteInfoBean bean=new SiteInfoBean(sWebAddr,sSavePath,sSaveName,5);

   SiteFileFetch fileFetch=new SiteFileFetch(bean);

   fileFetch.start();

  }

  catch(Exception e){

   e.printStackTrace();

  }

 }

 

 public static void main(String[] args){

  new TestMethod();

 }

}以上六个类的功能为: SiteFileFetch类负责下载整个文件以及控制FileSplitterFetch类的线程 FileSplitterFetch类负责下载部分(一块)文件 SiteInfoBean类提供下载整个文件所需要的信息,例如文件保存目录,文件名和下载文件的URL等信息 FileAccess类负责文件的存储 Utility为工具类,提供下载文件时所使用的方法 TestMethod类为测试类,执行该实例程序入口 在下载文件过程中,主要应用方法有: (1)完成与服务器连接 view plaincopy to clipboardprint?
URL    url=new   URL("下载文件url地址和文件名");  
 
HttpURLConnection   httpConnection=(HttpURLConnection)url.openConnection(); 

URL    url=new   URL("下载文件url地址和文件名");

HttpURLConnection   httpConnection=(HttpURLConnection)url.openConnection();(2)设置与服务器连接属性,即请求连接服务器信息 view plaincopy to clipboardprint?
httpConnection.setRequestProperty("User-Agent","NetFox"); 

httpConnection.setRequestProperty("User-Agent","NetFox");(3)设置下载文件的开始位置 view plaincopy to clipboardprint?
httpConnection.setRequestProperty("RANGE","bytes=0"); 

httpConnection.setRequestProperty("RANGE","bytes=0");(4)创建输入流,以输入流形式下载文件 view plaincopy to clipboardprint?
InputStream input=httpConnection.getInputStream(); 

InputStream input=httpConnection.getInputStream();(5)创建随机访问文件对象 view plaincopy to clipboardprint?
RandomAccess  oSavedFile=new RandomAccessFile("java.zip","rw"); 

RandomAccess  oSavedFile=new RandomAccessFile("java.zip","rw");(6)设置保存文件指针 view plaincopy to clipboardprint?
oSavedFile.seek(nPos); 

oSavedFile.seek(nPos);(7)保存文件 view plaincopy to clipboardprint?
byte[] b=new byte[1024];  
 
int nRead;  
 
while((nRead=input.read(b,0,1024))>0){  
 
        oSavedFile.write(b,0,nRead);  
 


本文来自CSDN博客,转载请标明出处:http://blog.csdn.net/kuyesuifeng/archive/2008/06/27/2591972.aspx

posted on 2010-05-09 22:12 fly 阅读(417) 评论(0)  编辑  收藏 所属分类: java学习

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