这是一个简单的基于客户端/服务器的 ping/pong 程序。不幸的是,IT 无法正常工作并显示以下错误消息:
java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(Unknown Source)
at java.net.SocketInputStream.read(Unknown Source)
at sun.nio.cs.StreamDecoder.readBytes(Unknown Source)
at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
at sun.nio.cs.StreamDecoder.read(Unknown Source)
at java.io.InputStreamReader.read(Unknown Source)
它停在 CLIENT TASK 30 行,实际上客户端不会读取服务器发送的内容。这里的代码:
服务器
package serverClient;
import java.net.*;
import java.io.*;
import java.util.concurrent.*;
public class Server {
public static void main(String[]args){
ExecutorService esp= Executors.newFixedThreadPool(50);
try(ServerSocket ss= new ServerSocket(1027)){
while(true){
try{
Socket s=ss.accept();
Callable<Void> task=new ServerTask(s);
esp.submit(task);
}
catch(BindException be){}
catch(ConnectException ce){}
catch(NoRouteToHostException nrthe){}
catch(IOException ioe){ioe.printStackTrace();}
}
}
catch(Exception e){e.printStackTrace();}
}
}
服务器任务
package serverClient;
import java.util.concurrent.*;
import java.net.*;
import java.io.*;
public class ServerTask implements Callable <Void> {
Socket s;
ServerTask(Socket s){
this.s=s;
}
public Void call(){
BufferedWriter writer=null;
BufferedReader reader=null;
try{
reader=new BufferedReader(new InputStreamReader(s.getInputStream()));
writer=new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));
int i=0;
StringBuilder sb=new StringBuilder();
while((i=reader.read())!=-1){
sb.append((char)i);
}
System.out.println("The client sends: "+sb);
writer.write("pong");
writer.flush();
}
catch(IOException ioe){ioe.printStackTrace();}
finally{
try {
writer.close();
}
catch (IOException ioe) {ioe.printStackTrace();}
if(reader!=null){
try{
reader.close();
}
catch(IOException ioe){ioe.printStackTrace();}
}
try{
s.close();
}
catch(IOException ioe){ioe.printStackTrace();}
}
return null;
}
}
客户
package serverClient;
import java.io.IOException;
import java.net.*;
import java.util.concurrent.*;
public class Client {
public static void main(String[] args) {
ExecutorService es= Executors.newSingleThreadExecutor();
try {
Socket s= new Socket(InetAddress.getLocalHost(),1027);
try {
s.setSoTimeout(50000);
}
catch(SocketException se){se.printStackTrace();}
Callable<Void> task=new ClientTask(s);
es.submit(task);
}
catch (UnknownHostException uhe) {uhe.printStackTrace();}
catch (IOException ioe) {ioe.printStackTrace();}
}
}
客户任务
package serverClient;
import java.util.concurrent.*;
import java.net.*;
import java.io.*;
public class ClientTask implements Callable <Void>{
Socket s;
ClientTask(Socket s){
this.s=s;
}
public Void call(){
BufferedWriter writer=null;
BufferedReader reader=null;
try{
writer=new BufferedWriter(new OutputStreamWriter(s.getOutputStream()));
reader=new BufferedReader(new InputStreamReader(s.getInputStream()));
writer.write("ping");
writer.flush();
int i=0;
StringBuilder sb=new StringBuilder();
while((i=reader.read())!=-1){
System.out.println("I'm reading.");
sb.append((char)i);
}
System.out.println("The server sends: "+sb);
}
catch(IOException ioe){ ioe.printStackTrace();}
finally{
try {
writer.close();
}
catch (IOException ioe) {ioe.printStackTrace();}
if(reader!=null){
try{
reader.close();
}
catch(IOException ioe){ioe.printStackTrace();}
}
try{
s.close();
}
catch(IOException ioe){ioe.printStackTrace();}
}
return null;
}
}