JAVA多线程Socket通信时遇到的问题???
实验过程中，服务器和客户端都能连接上了，但是服务器就是收不到客户端发来的字符串。
再贴一下代码：
//Mult.java
package t14_chapter;
import java.io.*;
import java.net.*;
class Mult extends Thread{
private Socket socket;
private BufferedReader in;
private PrintWriter out;
public Mult(Socket s)throws IOException{
socket =s;
in=new BufferedReader(new InputStreamReader(s.getInputStream()));
out=new PrintWriter(new OutputStreamWriter(s.getOutputStream()),true);
start();
}
public void run() {
try{
while(true){
String str=in.readLine();
//wait(1000);
if(str.equals("END"))
break;
System.out.println("Receiving and echoing:"+str);
out.println(str);
}
System.out.println("closing...");
}catch(IOException e){}
finally{
try{
socket.close();
}catch(IOException e){}
}
}
}
//ServerSocketMult.java
package t14_chapter;
import java.io.*;
import java.net.*;
public class ServerSocketMult {
static final int PORT=8080;
public static void main(String[] args)throws IOException{
ServerSocket s=new ServerSocket(PORT);
System.out.println("Server Startes");
try{
while(true){
Socket socket=s.accept();
System.out.println("Connection success!");
try{
new Mult(socket);
}
catch(IOException e){}
finally{
socket.close();
}
}
}
catch(IOException e){}
finally{
s.close();
}
}
}
//ClientSocketMultThread.java
package t14_chapter;
import java.io.*;
import java.net.*;
class ClientSocketMultThread extends Thread{
private Socket socket;
private BufferedReader in;
private PrintWriter out;
private static int counter=0;
private int id=counter++;
private static int threadcount=0;
public static int threadCount(){
return threadcount;
}
public ClientSocketMultThread(InetAddress addr){
System.out.println("Making client"+id);
threadcount++;
try{
socket =new Socket(addr,ServerSocketMult.PORT);
}catch(IOException e){
}
try{
in=new BufferedReader(new InputStreamReader(socket.getInputStream()));
out=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true);
start();
}catch(IOException e){
try{
socket.close();
}catch(IOException e2){}
}
}
public void run(){
try{
for(int i=0;i<25;i++){
out.println("Client"+id+"i");
String str=in.readLine();
System.out.println(str);
}
out.println("END");
}catch(IOException e){}
finally{
try{
socket.close();
}catch(IOException e){}
threadcount--;
}
}
}
//ClientSocketMult.java
package t14_chapter;
import java.io.*;
import java.net.*;
public class ClientSocketMult {
static final int MAX_THREADS=40;
public static void main(String[] args)throws IOException,InterruptedException{
InetAddress addr=InetAddress.getByName(null);
while(true){
if(ClientSocketMultThread.threadCount()<MAX_THREADS)
new ClientSocketMultThread(addr);
Thread.sleep(100);
}
}
}
跪求大神求救！！！！
测试了你的代码，存在的问题如下：
1 你的ServerSocketMult类的finally{socket.close();}导致你的Mul线程刚开始处理Socket时，这个socket就已经关闭了。所以这个操作多余而且还是问题的根源，因为你已经咋Mul类处理完成后写了socket.close代码了。
2 ClientSocketMult这个类启动指定N个线程，所以对线程数的操作threadcount--;是在多个线程中的，需要对threadcount变量进行同步操作。
3 所有的异常分支，你都是空语句，所以淹没了异常导致你无法排错。其实收不到响应数据就是因为1中你关闭了Socket导致的，只要打印了异常就很容易定位的。
修正ServerSocketMult代码：
public class ServerSocketMult {
static final int PORT = 8080;
public static void main(String[] args) throws IOException {
ServerSocket s = new ServerSocket(PORT);
System.out.println("Server Startes");
try {
while (true) {
Socket socket = s.accept();
System.out.println("Connection success!");
new Mult(socket);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
s.close();
}
}
}
再修正Mult
class Mult extends Thread {
private Socket socket;
private BufferedReader in;
private PrintWriter out;
public Mult(Socket s) throws IOException {
socket = s;
in = new BufferedReader(new InputStreamReader(s.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(s.getOutputStream()), true);
start();
}
public void run() {
System.out.println("print received ...");
try {
String str = in.readLine();
StringBuffer buffer = new StringBuffer();
//读取Socket的请求数据，并回应
while (str!=null&&!str.equals("END")) {
buffer.append(str);
str = in.readLine();
}
String value = buffer.toString();
out.println(value);
System.out.println("Receiving and echoing:" + value);
System.out.println("closing...");
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
修正ClientSocketMultThread
class ClientSocketMultThread extends Thread {
private Socket socket;
private BufferedReader in;
private PrintWriter out;
private static int counter = 0;
private int id = counter++;
private static int threadcount = 0;
public synchronized static int threadCount() {
return threadcount;
}
public synchronized static void addThreadCount(){
threadcount++;
}
public synchronized static void descThreadCount(){
threadcount--;
}
public ClientSocketMultThread(InetAddress addr) {
System.out.println("Making client" + id);
threadcount++;
try {
socket = new Socket(addr, ServerSocketMult.PORT);
} catch (IOException e) {
}
try {
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())), true);
start();
} catch (IOException e) {
try {
socket.close();
} catch (IOException e2) {
}
}
}
public void run() {
try {
for (int i = 0; i < 25; i++) {
out.println("Client" + id + i);
}
out.println("END");
String str = in.readLine();
System.out.println("getResponse:"+str);
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
socket.close();
} catch (IOException e) {
}
descThreadCount();
}
}
}
测试Ok，就能收到正确的请求及回复信息。