跪求android单线程下载报错解决办法
报错如下
java.net.SocketException: Connection reset by peer: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(Unknown Source)
at java.net.SocketOutputStream.write(Unknown Source)
at com.gaoyunfeng.uplooking.www.server.AndroidServer.main

Java code

package com.download;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.net.Socket;import java.net.UnknownHostException;import android.app.Activity;import android.os.AsyncTask;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.ProgressBar;public class DownloadFileActivity extends Activity {    public ProgressBar pb;    Button btn;    int progress  = 0;    MyAnysTask  myAnysTask;    /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        pb = (ProgressBar) findViewById(R.id.progressBar1);        btn = (Button) findViewById(R.id.button1);        btn.setOnClickListener(new OnClickListener() {            public void onClick(View v) {                // TODO Auto-generated method stub              myAnysTask =   new  MyAnysTask();             myAnysTask.execute("a1.mp3");             btn.setEnabled(false);                            }        });    }    @Override    protected void onDestroy() {        finish();        // TODO Auto-generated method stub        super.onDestroy();            }    class MyAnysTask extends AsyncTask<String, Integer, String> {        @Override        protected void onProgressUpdate(Integer... values) {            // TODO Auto-generated method stub            progress +=  values[0];            pb.setProgress(progress);            super.onProgressUpdate(values);        }        @Override        protected String doInBackground(String... params) {            Socket socket = null;            InputStream inputStream = null ;            OutputStream outputStream = null ;            OutputStream fileout = null;            try {                socket = new Socket("192.168.1.100", 9999);                byte[] buffer = new byte[8 * 1024];                 inputStream = socket.getInputStream();                outputStream = socket.getOutputStream();                outputStream.write(params[0].getBytes());                // 设置pb的max                    inputStream.read(buffer);                 System.out.println("buffer"+new String(buffer).trim());                 if (new String(buffer).trim() != null) {                     int filecinmax = Integer.parseInt(new String(buffer).trim());                     pb.setMax(filecinmax);                }                                outputStream.write("hello".getBytes());                // 开始下载文件                File file = new File("/sdcard/a1.mp3");                if (file.exists()) {                    file.delete();                }                file.createNewFile();                int count = 0;                 fileout = new FileOutputStream(file);                do {                    count = inputStream.read(buffer);                    fileout.write(buffer, 0, count);                    publishProgress(8);                } while (count == buffer.length);                            } catch (UnknownHostException e) {                // TODO Auto-generated catch block                e.printStackTrace();            } catch (IOException e) {                                e.printStackTrace();            }finally{                try {                    fileout.close();                    inputStream.close();                    outputStream.close();                    socket.close();                } catch (IOException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }                            }            return null;        }    }} 
 

下面是server端

Java code

package Server;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.net.ServerSocket;import java.net.Socket;public class Serv {    public static void main(String[] args) {        ServerSocket ss = null;        InputStream in = null ;        Socket client = null;        InputStream filein = null ;        OutputStream outputStream = null;        try {            byte[] buffer = new byte[1024 * 8];            ss = new ServerSocket(9999);            client = ss.accept();            // 首先读取要下载的文件名            in = client.getInputStream();            outputStream = client.getOutputStream();            in.read(buffer);            String filename = "D:\\music\\" + new String(buffer).trim();            File file = new File(filename);            if (file.exists()) {                // 读取文件大小传递给客户端                int count = 0;                count = (int) (file.length() / 1024);                outputStream.write(("" + count).getBytes());                // 开始向客户端发送文件 前确定连接                buffer = new byte[8 * 1024];                in.read(buffer);                if (new String(buffer).trim().equals("hello")) {                    filein = new FileInputStream(file);                    do {                        count = filein.read(buffer);                        System.out.println(count + "");                        outputStream.write(buffer, 0, count);                    } while (count == buffer.length);                    System.out.println("发送完成");                    filein.close();                }            }            in.close();            outputStream.close();            client.close();            ss.close();        } catch (IOException e) {            e.printStackTrace();        } finally {            try {                in.close();                outputStream.close();                client.close();                ss.close();            } catch (IOException e) {                // TODO Auto-generated catch block                e.printStackTrace();            }                    }    }}

[解决办法]
貌似是在服务器端还没有写完的情况下，客户端关闭了链接，导致服务器端write报错
[解决办法]
问题在 while (count == buffer.length); 这个判断语句上

在 java IO 里 inputStream.read(buffer) 这样的代码是不保证一定会填满字节数组的，特别是在网络连接上，更是非常的不可靠。
[解决办法]
流换一下，用DataOutputStream dos = new DataOutputStream(socket.getOutputStream);
输入流也一样，客户端服务端都一样，一般没有直接用SocketOutputStream来读写数据的吧，至少我没用过
[解决办法]
在write之后flush（）一下