Udp server/client, java GUI，选择题
Udp server/client, java GUI, multiple choice questions
下面你会看到我的客户端和服务器代码。
我快完成了，我的问题是当用户提交 A 问题的答案时，当服务器接收到它时，我无法通过问题协议（在服务器代码中）处理它).
显示结果，即1/3、0/3等
如果你能帮我解决这个问题，因为我已经坚持了一个星期了，试图找出为什么我不能让结果部分正常工作，我想我有某种我的问题协议中的一个主要缺陷，但我没有识别它的专业知识。
这是我的服务器代码：
import java.net.*;
import java.io.*;
public class UdpServer extends Thread
{
//final static int port = 5600;
public static void main(String[] args)
{
try
{
new UdpServer().startServer();//creating an object of my class to start up the server.
}
//catch any exceptions that might occure and print the stack.
catch (Exception e)
{
System.out.println("failure: " + e.getMessage());
e.printStackTrace();
}
}
public void startServer() throws Exception
{
DatagramSocket serverSocket = null;//intiailise the socket to null.
boolean listening = true;//check for connections/
try
{
serverSocket = new DatagramSocket(5600);//attach a port to the server socket we are sign in this case its the port we wanted at the start.
byte[] receiveStuff = new byte[1024];
byte[] sendStuff = new byte[1024];
while (listening)
{
DatagramPacket Packet = new DatagramPacket(receiveStuff,receiveStuff.length);
serverSocket.receive(Packet);
InetAddress IPAddress = Packet.getAddress();
int port = Packet.getPort();
String lineInput=null, lineOutput = null;
QuestionLogic questionLogic = new QuestionLogic();//creating a logic section where the questions protocol takes places, this case its called question logic.
lineOutput = questionLogic.processInput(null);//make the output coming from the logic side, i,e fetch whatever is happening within the logic.
lineInput = new String (receiveStuff, 0, Packet.getLength());
System.out.println("Server Received----"+lineInput);
/*if(lineInput.equals("hello"))
{
lineOutput = "Thank you for using this system";
System.out.println(lineOutput);
}*/
Packet.setLength(receiveStuff.length);
lineOutput = questionLogic.processInput(lineInput);
System.out.println("Server Sending----"+lineOutput);
sendStuff = lineOutput.getBytes();
Packet = new DatagramPacket(sendStuff, sendStuff.length, IPAddress, port);
//DatagramPacket sendPacket = new DatagramPacket(sendStuff,sendStuff.length, IPAddress, port);
serverSocket.send(Packet);
Packet.setLength(sendStuff.length);
}
}
catch (IOException e)
{
System.err.println("could not connect: " );
System.exit(-1);
}
serverSocket.close();
}
//this is where the question logic get carried out, in other word a questions protocol,.
public static class QuestionLogic
{
private static final int Hello = 0;
private static final int Answer = 1;
private static final int Result = 2;
private static final int question2 = 3;
private static final int Result2 = 4;
private static final int question3 = 5;
private static final int Result3 = 6;
private int state = Hello;
private int res = 0;
private String CorrectAnswer = null;
//according to the client request sort out what will be happening, in different states, goin through 3 questions returning a reply each time.
public String processInput(String clientRequest)
{
String reply = null;
try
{
if(clientRequest != null && clientRequest.equalsIgnoreCase("C"))
{
res++;
reply = "One"+res;
}
//these were originally for testing purposes using cmd, left in here in case in the future any further testing is required
if(clientRequest != null && clientRequest.equalsIgnoreCase("Hello"))
{
state = Hello;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("B"))
{
res++;
reply = "two"+res;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("A"))
{
res++;
reply = "three"+res;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("question1"))
{
state = Answer;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("question2"))
{
state = question2;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("question3"))
{
state = question3;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("Result"))
{
state = Result3;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("exit")) {
return "exit";
}
//starting with a connection check to confirm server is connected to client.
if(state == Hello)
{
reply = "Connected, Press Next To continue";
state = Answer;
}
//we begin with the first question sent to the client.
else if(state == Answer)
{
reply = "Q1: (A + B)*(A+B) \n\n A)A*A + B*B \n\n B)A*A +A*B + B*B \n\n C)A*A +2*A*B + B*B \n\n ";
}
//check if the answer from the user is the correct one, and increment or do nothing to the result
else if(state == question2)
{
reply = "Q2: (A + B)*(A - B) \n\n A) A*A + 2*B*B \n\n B) A*A - B*B\n\n C)A*A -2*A*B + B*B\n\n ";
}
else if(state == question3)
{
reply = "Q3: sin(x)*sin(x) + cos(x)*cos(x)\n\n A)1\n\n B)2\n\n C)3\n\n";
}
//finally we printout the result at the end for the client to see.
else if(state == Result3)
{
if(res == 0)
{
reply ="Sorry you failed 0/3";
}
if(res == 1)
{
reply ="You got 1/3";
}
if(res == 2)
{
reply ="You got 2/3";
}
if(res == 3)
{
reply ="You got 3/3";
}
}
}
catch(Exception e)
{
System.out.println("input process failed: " + e.getMessage());
return "exit";
}
return reply;//we return the reply from this method to be used.
}
}
}
这是我的客户端代码：
import javax.swing.*;//for the main components design (JFrame etc).
import java.awt.*; //main GUI manipulation.
import java.net.*;//for socket and network programming such as ServerSockets etc.
import java.io.*; //for main editing utilities (inputs/outputs).
import java.awt.event.*; //Event manipulation
//creating my main client class.
class UdpClient
{
//constructor
public static void main (String[] args)
{
try
{ //create an object of the class where i can carry out my code.
UdpClient c = new UdpClient();
}
catch(Exception ex)
{
System.out.println("Major Error" + ex.getMessage());
ex.printStackTrace();
}
}
//all public variables i would like to access through out my code.
JFrame build;//the main frame of the client
JLabel ans,Label; // labels for names and instructions.
JComboBox options,request;
JButton b1,b2;//2 buttons for next and exit.
JTextArea txt1,txt3;//txt area for the actual questions.
JTextField txt2;// txtfield to take in user answer.
DatagramSocket clientSocket;//client socket.
DatagramPacket sendPacket, receivePacket;
byte[] sendData;
byte[] receiveData;
String clientMsg = null,serverMsg,lineInput;
InetAddress IPAddress = null;//for hostname solutions.
//the next few lines, their names explain what they are for.
//the object we created earlier where the code will mainly be discussed.
UdpClient()
{
//creating the actual gui, addinng everything into the build, naming them, and setting their positions.
build = new JFrame ("Client");
Label = new JLabel();
Label.setText("Client Interface");
Label.setForeground(Color.blue);
Label.setBounds(300,0,400,50);
build.add(Label);
//creatin text area for the questions and setting colours and position
txt1 = new JTextArea();
txt1.setBackground(Color.cyan);
txt1.setForeground(Color.blue);
txt1.setEditable(false);
txt1.setBounds(50,50,300,500);
build.add(txt1);
//creating text field for the answer display/
txt2 = new JTextField();
txt2.setEditable(false);
txt2.setBounds(500,450,50,50);
build.add(txt2);
/*/text area for the instructions of how to use the programme.
txt3 = new JTextArea("Instructions:\n\n Press Next to Begin\n\n Question Appears\n\n Select Answer From List\n\n Press Next\n\n Wait For Confirmation\n\n Press Next\n\n If Result Appears\n\n Press Exit\n");
txt3.setForeground(Color.red);
txt3.setBackground(Color.lightGray);
txt3.setEditable(false);
txt3.setBounds(400,150,200,270);
build.add(txt3);*/
ans = new JLabel("Answer");
ans.setBounds(400,450,100,50);
build.add(ans);
b1 = new JButton("Next");
b1.setBounds(500,500,100,50);
build.add(b1);
b2= new JButton("start");
b2.setBounds(400,500,100,50);
build.add(b2);
//creating a combo box for the user to choose answers from.
options = new JComboBox();
options.addItem("A");
options.addItem("B");
options.addItem("C");
options.addActionListener(new ActionListener()//adding actions listeners to the choices to add the answer of the user into the txt field answer area.
{
public void actionPerformed(ActionEvent e)
{
if(options.getSelectedItem().equals("A"))
{
txt2.setText("A");
}
if(options.getSelectedItem().equals("B"))
{
txt2.setText("B");
}
if(options.getSelectedItem().equals("C"))
{
txt2.setText("C");
}
}
});
b1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ev)
{
if(ev.getSource() == b1)
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = txt2.getText();
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
clientSocket.close();
}
catch(UnknownHostException ex1)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex1)
{
System.exit(1);
}
}
}
});
request= new JComboBox();
request.addItem("QuestionOne");
request.addItem("QuestionTwo");
request.addItem("QuestionThree");
request.addItem("Result");
request.addActionListener(new ActionListener()//adding actions listeners to the choices to add the answer of the user into the txt field answer area.
{
public void actionPerformed(ActionEvent e)
{
if(request.getSelectedItem().equals("QuestionOne"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "question1";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
if(request.getSelectedItem().equals("QuestionTwo"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "question2";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
if(request.getSelectedItem().equals("QuestionThree"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "question3";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
if(request.getSelectedItem().equals("Result"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "Result";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
}
});
//start button
b2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ev1)
{
if(ev1.getSource() == b2)
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "Hello";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException e)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException e)
{
System.exit(1);
}
}
}
});
options.setBounds(450,450,50,50);
request.setBounds(400,150,200,270);
build.add(options);
build.add(request);
build.setLayout(null);//setting build layout.
build.setSize(700,600);//the size of the main window.
build.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//close when X is pressed.
build.setVisible(true);//enable it so it appears.
build.setResizable(false);//make it a fixed sized so user cant change it, e.g maximize it.
//a try catch, to do all the networking aspect of the client side inside of.
}
}
我解决了这个问题，最后使用数据库来解决问题。
下面你会看到我的客户端和服务器代码。
我快完成了，我的问题是当用户提交 A 问题的答案时，当服务器接收到它时，我无法通过问题协议（在服务器代码中）处理它). 显示结果，即1/3、0/3等
如果你能帮我解决这个问题，因为我已经坚持了一个星期了，试图找出为什么我不能让结果部分正常工作，我想我有某种我的问题协议中的一个主要缺陷，但我没有识别它的专业知识。
这是我的服务器代码：
import java.net.*;
import java.io.*;
public class UdpServer extends Thread
{
//final static int port = 5600;
public static void main(String[] args)
{
try
{
new UdpServer().startServer();//creating an object of my class to start up the server.
}
//catch any exceptions that might occure and print the stack.
catch (Exception e)
{
System.out.println("failure: " + e.getMessage());
e.printStackTrace();
}
}
public void startServer() throws Exception
{
DatagramSocket serverSocket = null;//intiailise the socket to null.
boolean listening = true;//check for connections/
try
{
serverSocket = new DatagramSocket(5600);//attach a port to the server socket we are sign in this case its the port we wanted at the start.
byte[] receiveStuff = new byte[1024];
byte[] sendStuff = new byte[1024];
while (listening)
{
DatagramPacket Packet = new DatagramPacket(receiveStuff,receiveStuff.length);
serverSocket.receive(Packet);
InetAddress IPAddress = Packet.getAddress();
int port = Packet.getPort();
String lineInput=null, lineOutput = null;
QuestionLogic questionLogic = new QuestionLogic();//creating a logic section where the questions protocol takes places, this case its called question logic.
lineOutput = questionLogic.processInput(null);//make the output coming from the logic side, i,e fetch whatever is happening within the logic.
lineInput = new String (receiveStuff, 0, Packet.getLength());
System.out.println("Server Received----"+lineInput);
/*if(lineInput.equals("hello"))
{
lineOutput = "Thank you for using this system";
System.out.println(lineOutput);
}*/
Packet.setLength(receiveStuff.length);
lineOutput = questionLogic.processInput(lineInput);
System.out.println("Server Sending----"+lineOutput);
sendStuff = lineOutput.getBytes();
Packet = new DatagramPacket(sendStuff, sendStuff.length, IPAddress, port);
//DatagramPacket sendPacket = new DatagramPacket(sendStuff,sendStuff.length, IPAddress, port);
serverSocket.send(Packet);
Packet.setLength(sendStuff.length);
}
}
catch (IOException e)
{
System.err.println("could not connect: " );
System.exit(-1);
}
serverSocket.close();
}
//this is where the question logic get carried out, in other word a questions protocol,.
public static class QuestionLogic
{
private static final int Hello = 0;
private static final int Answer = 1;
private static final int Result = 2;
private static final int question2 = 3;
private static final int Result2 = 4;
private static final int question3 = 5;
private static final int Result3 = 6;
private int state = Hello;
private int res = 0;
private String CorrectAnswer = null;
//according to the client request sort out what will be happening, in different states, goin through 3 questions returning a reply each time.
public String processInput(String clientRequest)
{
String reply = null;
try
{
if(clientRequest != null && clientRequest.equalsIgnoreCase("C"))
{
res++;
reply = "One"+res;
}
//these were originally for testing purposes using cmd, left in here in case in the future any further testing is required
if(clientRequest != null && clientRequest.equalsIgnoreCase("Hello"))
{
state = Hello;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("B"))
{
res++;
reply = "two"+res;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("A"))
{
res++;
reply = "three"+res;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("question1"))
{
state = Answer;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("question2"))
{
state = question2;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("question3"))
{
state = question3;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("Result"))
{
state = Result3;
}
if(clientRequest != null && clientRequest.equalsIgnoreCase("exit")) {
return "exit";
}
//starting with a connection check to confirm server is connected to client.
if(state == Hello)
{
reply = "Connected, Press Next To continue";
state = Answer;
}
//we begin with the first question sent to the client.
else if(state == Answer)
{
reply = "Q1: (A + B)*(A+B) \n\n A)A*A + B*B \n\n B)A*A +A*B + B*B \n\n C)A*A +2*A*B + B*B \n\n ";
}
//check if the answer from the user is the correct one, and increment or do nothing to the result
else if(state == question2)
{
reply = "Q2: (A + B)*(A - B) \n\n A) A*A + 2*B*B \n\n B) A*A - B*B\n\n C)A*A -2*A*B + B*B\n\n ";
}
else if(state == question3)
{
reply = "Q3: sin(x)*sin(x) + cos(x)*cos(x)\n\n A)1\n\n B)2\n\n C)3\n\n";
}
//finally we printout the result at the end for the client to see.
else if(state == Result3)
{
if(res == 0)
{
reply ="Sorry you failed 0/3";
}
if(res == 1)
{
reply ="You got 1/3";
}
if(res == 2)
{
reply ="You got 2/3";
}
if(res == 3)
{
reply ="You got 3/3";
}
}
}
catch(Exception e)
{
System.out.println("input process failed: " + e.getMessage());
return "exit";
}
return reply;//we return the reply from this method to be used.
}
}
}
这是我的客户端代码：
import javax.swing.*;//for the main components design (JFrame etc).
import java.awt.*; //main GUI manipulation.
import java.net.*;//for socket and network programming such as ServerSockets etc.
import java.io.*; //for main editing utilities (inputs/outputs).
import java.awt.event.*; //Event manipulation
//creating my main client class.
class UdpClient
{
//constructor
public static void main (String[] args)
{
try
{ //create an object of the class where i can carry out my code.
UdpClient c = new UdpClient();
}
catch(Exception ex)
{
System.out.println("Major Error" + ex.getMessage());
ex.printStackTrace();
}
}
//all public variables i would like to access through out my code.
JFrame build;//the main frame of the client
JLabel ans,Label; // labels for names and instructions.
JComboBox options,request;
JButton b1,b2;//2 buttons for next and exit.
JTextArea txt1,txt3;//txt area for the actual questions.
JTextField txt2;// txtfield to take in user answer.
DatagramSocket clientSocket;//client socket.
DatagramPacket sendPacket, receivePacket;
byte[] sendData;
byte[] receiveData;
String clientMsg = null,serverMsg,lineInput;
InetAddress IPAddress = null;//for hostname solutions.
//the next few lines, their names explain what they are for.
//the object we created earlier where the code will mainly be discussed.
UdpClient()
{
//creating the actual gui, addinng everything into the build, naming them, and setting their positions.
build = new JFrame ("Client");
Label = new JLabel();
Label.setText("Client Interface");
Label.setForeground(Color.blue);
Label.setBounds(300,0,400,50);
build.add(Label);
//creatin text area for the questions and setting colours and position
txt1 = new JTextArea();
txt1.setBackground(Color.cyan);
txt1.setForeground(Color.blue);
txt1.setEditable(false);
txt1.setBounds(50,50,300,500);
build.add(txt1);
//creating text field for the answer display/
txt2 = new JTextField();
txt2.setEditable(false);
txt2.setBounds(500,450,50,50);
build.add(txt2);
/*/text area for the instructions of how to use the programme.
txt3 = new JTextArea("Instructions:\n\n Press Next to Begin\n\n Question Appears\n\n Select Answer From List\n\n Press Next\n\n Wait For Confirmation\n\n Press Next\n\n If Result Appears\n\n Press Exit\n");
txt3.setForeground(Color.red);
txt3.setBackground(Color.lightGray);
txt3.setEditable(false);
txt3.setBounds(400,150,200,270);
build.add(txt3);*/
ans = new JLabel("Answer");
ans.setBounds(400,450,100,50);
build.add(ans);
b1 = new JButton("Next");
b1.setBounds(500,500,100,50);
build.add(b1);
b2= new JButton("start");
b2.setBounds(400,500,100,50);
build.add(b2);
//creating a combo box for the user to choose answers from.
options = new JComboBox();
options.addItem("A");
options.addItem("B");
options.addItem("C");
options.addActionListener(new ActionListener()//adding actions listeners to the choices to add the answer of the user into the txt field answer area.
{
public void actionPerformed(ActionEvent e)
{
if(options.getSelectedItem().equals("A"))
{
txt2.setText("A");
}
if(options.getSelectedItem().equals("B"))
{
txt2.setText("B");
}
if(options.getSelectedItem().equals("C"))
{
txt2.setText("C");
}
}
});
b1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ev)
{
if(ev.getSource() == b1)
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = txt2.getText();
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
clientSocket.close();
}
catch(UnknownHostException ex1)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex1)
{
System.exit(1);
}
}
}
});
request= new JComboBox();
request.addItem("QuestionOne");
request.addItem("QuestionTwo");
request.addItem("QuestionThree");
request.addItem("Result");
request.addActionListener(new ActionListener()//adding actions listeners to the choices to add the answer of the user into the txt field answer area.
{
public void actionPerformed(ActionEvent e)
{
if(request.getSelectedItem().equals("QuestionOne"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "question1";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
if(request.getSelectedItem().equals("QuestionTwo"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "question2";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
if(request.getSelectedItem().equals("QuestionThree"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "question3";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
if(request.getSelectedItem().equals("Result"))
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "Result";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException ex)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException ex)
{
System.exit(1);
}
}
}
});
//start button
b2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ev1)
{
if(ev1.getSource() == b2)
{
try
{
clientSocket = new DatagramSocket();
sendData = new byte[1024];
receiveData = new byte[1024];
IPAddress = InetAddress.getByName("localhost");
clientMsg = "Hello";
sendData = clientMsg.getBytes();
sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, 5600);
clientSocket.send(sendPacket);
receivePacket = new DatagramPacket(receiveData, receiveData.length);
clientSocket.receive(receivePacket);
serverMsg = new String (receiveData, 0, receivePacket.getLength());
txt1.setText(serverMsg);
clientSocket.close();
}
catch(UnknownHostException e)
{
System.err.println("no host: ");
System.exit(1);
}
catch(IOException e)
{
System.exit(1);
}
}
}
});
options.setBounds(450,450,50,50);
request.setBounds(400,150,200,270);
build.add(options);
build.add(request);
build.setLayout(null);//setting build layout.
build.setSize(700,600);//the size of the main window.
build.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//close when X is pressed.
build.setVisible(true);//enable it so it appears.
build.setResizable(false);//make it a fixed sized so user cant change it, e.g maximize it.
//a try catch, to do all the networking aspect of the client side inside of.
}
}
我解决了这个问题，最后使用数据库来解决问题。