我应该编写一个程序，将一些.class文件作为服务，并且应该加载它们并执行服务。我已经使用套接字编程完成了它，但由于我已经使它成为多线程，所以服务可以被任意数量的客户端使用，我得到套接字关闭异常，它发生在每个客户端线程完成后的无限循环中。即使有一个客户端我仍然得到这个例外。我没有得到异常的唯一一次是没有加载的类我使用break。我试图找到问题并搜索了很多，但我找不到任何东西。 //这是服务器端的主要类
package reg.main;
import java.net.*;
import java.io.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.*;
import java.util.concurrent.*;
public class Application{
private final static Logger LOGGER = LoggerFactory.getLogger(Application.class);
public static void main(String[] args){
while(true){
InputStream input = null;
Properties prop = new Properties();
try{
String filename = "config.properties";
input = Application.class.getClassLoader().getResourceAsStream(filename);
if(input == null){
System.out.println("Sorry, unable to find " + filename);
}
prop.load(input);
}
catch(IOException ex){
System.out.println("properties file does not exist.");
}
try{
String port = prop.getProperty("port");
int portNo = Integer.parseInt(port);
ServerSocket serverSocket = new ServerSocket(portNo);
LOGGER.debug("Server is listening... on port " + portNo);
ExecutorService service = Executors.newFixedThreadPool(1);
service.execute(new Server(serverSocket.accept()));
serverSocket.close();
service.shutdown();
}catch (IOException e) {
System.out.println("Could not close socket");
System.exit(1);
}
}
}
}
// this is server side code
package reg.main;
import java.net.*;
import java.io.*;
import reg.entity.*;
import reg.utility.*;
import reg.service.*;
import reg.dao.*;
import java.util.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Server implements Runnable{
private static final Logger LOGGER = LoggerFactory.getLogger(Server.class);
private Socket clientSocket;
public Server(Socket clientSocket){
LOGGER.debug("Connection is Established.");
this.clientSocket = clientSocket;
}
public void run(){
ObjectOutputStream outToClient = null;
ObjectInputStream inFromClient = null;
try{
outToClient = new ObjectOutputStream(clientSocket.getOutputStream());
inFromClient = new ObjectInputStream(clientSocket.getInputStream());
}
catch(IOException ex){
LOGGER.error("There is a problem in reading or writing.");
}
while(true){
try{
String userOption =(String)inFromClient.readObject();//while printing stack trace, it says there is something wrong with this line. i don't know why!
System.out.println(userOption);
userOption = DataEditor.editOptionInputInfo(userOption); //this is a custom method
Map<String,Service> mapper= CustomClassLoader.loadClass(); //in class loader .class files will be loaded and an object of each of them will be sent in a map
if(mapper == null){
LOGGER.debug("no class file found to be loaded.");
clientSocket.close();
break;
}
List<String> classNames = CustomClassLoader.getClassNames();
boolean ckeckedUserOption = Validation.validUserOption(classNames,userOption);
if(ckeckedUserOption == false){
LOGGER.error("client has entered the wrong option.");
}
System.out.println(userOption + "in server class------------- before loading class");
Service service = mapper.get(userOption);
List<String> parameters = service.getRequiredParameters();
if(parameters.size() == 0){
LOGGER.debug("There is a problem with loaded classes.");
}
outToClient.writeObject(parameters);
LOGGER.debug("required parameters was sent to client.");
List<String>info = (List<String>)inFromClient.readObject();
LOGGER.debug("Information from client has been sent.");
if(info.size() == 0){
LOGGER.error("client has not put information. Try again.");
System.exit(2);
}
String result = service.doOperation(info);
outToClient.writeObject(result);
LOGGER.debug("Result of required service was sent to client.");
inFromClient.close();
outToClient.close();
//clientSocket.close();
}catch(IOException ex){
LOGGER.error("Exception caught when trying to listen on port "
+ " or listening for a connection");
ex.printStackTrace();
}
catch(ClassNotFoundException ex){
LOGGER.error("class was not found.");
}
}
}
}
// this is client side
package reg.main;
import java.net.*;
import java.io.*;
import java.util.*;
import java.util.Scanner;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
//Client class
public class Client{
private final static Logger LOGGER = LoggerFactory.getLogger(Client.class);
public static void main(String[] args){
Socket clientSocket = null;
String userOption;
InputStream inputStream = null;
Properties prop = new Properties();
try{
String filename = "config.properties";
inputStream = Client.class.getClassLoader().getResourceAsStream(filename);
if(inputStream == null){
System.out.println("Sorry, unable to find " + filename);
}
prop.load(inputStream);
}
catch(IOException ex){
System.out.println("properties file does not exist.");
}
try{
Scanner input = new Scanner(System.in);
System.out.println("Do you want to sign in or login? put the file name in:");
String path = input.next();
LOGGER.debug("User entered " + path + " as the service option.");
String port = prop.getProperty("port");
int portNo = Integer.parseInt(port);
FileReader fileReader = new FileReader(path);
BufferedReader reader = new BufferedReader(fileReader);
userOption = reader.readLine();
clientSocket = new Socket("192.168.121.114", portNo);
System.out.println("client is connected to the server.");
ObjectOutputStream outToServer = new ObjectOutputStream(clientSocket.getOutputStream());
ObjectInputStream inFromServer = new ObjectInputStream(clientSocket.getInputStream());
outToServer.writeObject(userOption);
LOGGER.debug("sent the user option to server ==> " + userOption);
List<String> listOfparams =(List<String>)inFromServer.readObject();
LOGGER.debug("List of Requierements in Client " + listOfparams);
List<String> info = new ArrayList<String>();
for(String param : listOfparams){
System.out.println("Enter your " + param + ": ");
info.add(input.next());
}
outToServer.writeObject(info);
String result = (String)inFromServer.readObject();
LOGGER.debug("The result of required service: " + result);
System.out.println(clientSocket.isClosed());
inFromServer.close();
outToServer.close();
clientSocket.close();
} catch (UnknownHostException e) {
LOGGER.error("Don't know about host ");
System.exit(1);
} catch (IOException e){
LOGGER.error("Couldn't get I/O for the connection to the host or there is no service for loading");
System.exit(1);
}
catch(ClassNotFoundException ex){
LOGGER.error("class does not found.");
}
}
}
我感谢任何帮助。提前谢谢你
答案 0 :(得分：1)
在catch
中使用break
try{
String filename = "config.properties";
input = Application.class.getClassLoader().getResourceAsStream(filename);
if(input == null){
System.out.println("Sorry, unable to find " + filename);
}
prop.load(input);
}
catch(IOException ex){
System.out.println("properties file does not exist.");
break; // this make program to go out of the loop
}