问题描述
当我直接运行客户端文件时，我正在开发一个多客户端聊天应用程序的项目，但是它工作正常，但是当我尝试从其他文件（例如新的jframe）中调用它时，它却无法正常工作。
ChatClientGuiTEST.java
enter code here
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package chating;
import java.awt.Frame;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;
import java.sql.*;
import javax.swing.*;
import javax.swing.JOptionPane;
import javax.swing.JScrollBar;
import javax.swing.JScrollPane;
import javax.swing.table.DefaultTableModel;
import javax.swing.text.DefaultCaret;
/**
*
* @author Hello
*/
public class ChatClientGuiTEST extends javax.swing.JFrame {
BufferedReader in;
PrintWriter out;
ResultSet rs;
//SignUp obj;
public ChatClientGuiTEST() throws IOException {
initComponents();
pack();
setSize(406, 600);
setResizable(false);
//jLabel2.setText(usern);
jLabel2.setVisible(true);
//jTextArea1.setVisible(false);
jTextField1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (jTextField1.getText().trim().length() != 0) {
try {
out.println(jTextField1.getText());
} catch (Exception ev) {
System.out.println(ev);
}
jTextField1.setText("");
}
}
});
jTextField1.requestFocusInWindow();
try {
connection obj = new connection();
String query = "SELECT * FROM tb_online";
connection.pst = connection.con.prepareStatement(query);
rs = connection.pst.executeQuery();
while (rs.next()) {
String online_user = rs.getString("online_user");
Object[] row = {online_user};
DefaultTableModel model = (DefaultTableModel) jTable1.getModel();
model.addRow(row);
}
} catch (Exception e) {
JOptionPane.showMessageDialog(this, "UNABLE TO FETCH DATA" + e, "ERROR", 0);
}
this.setVisible(true);
//run();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">//GEN-BEGIN:initComponents
private void initComponents() {
jTextField1 = new javax.swing.JTextField();
jScrollPane1 = new javax.swing.JScrollPane();
jTextArea1 = new javax.swing.JTextArea();
jLabel2 = new javax.swing.JLabel();
jLabel1 = new javax.swing.JLabel();
jButton1 = new javax.swing.JButton();
jButton2 = new javax.swing.JButton();
jScrollPane2 = new javax.swing.JScrollPane();
jTable1 = new javax.swing.JTable();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
getContentPane().setLayout(null);
jTextField1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jTextField1ActionPerformed(evt);
}
});
getContentPane().add(jTextField1);
jTextField1.setBounds(0, 530, 400, 40);
jTextArea1.setColumns(20);
jTextArea1.setRows(5);
jTextArea1.setMinimumSize(new java.awt.Dimension(4, 400));
jTextArea1.setSelectionColor(new java.awt.Color(51, 0, 51));
jScrollPane1.setViewportView(jTextArea1);
jTextArea1.setEditable(false);
jTextArea1.setLineWrap(true);
DefaultCaret caret = (DefaultCaret)jTextArea1.getCaret();
caret.setUpdatePolicy(DefaultCaret.ALWAYS_UPDATE);
getContentPane().add(jScrollPane1);
jScrollPane1.setBounds(0, 70, 400, 460);
jLabel2.setText("jLabel1");
getContentPane().add(jLabel2);
jLabel2.setBounds(340, 390, 50, 14);
jLabel1.setFont(new java.awt.Font("Urdu Typesetting", 3, 18)); // NOI18N
jLabel1.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
jLabel1.setText("WELCOME USER TO CHATZONE");
getContentPane().add(jLabel1);
jLabel1.setBounds(0, 0, 400, 30);
jButton1.setText("LOAD PREVIOUS MESSAGES");
getContentPane().add(jButton1);
jButton1.setBounds(3, 40, 170, 23);
jButton2.setText("VIEW ONLINE USER");
jButton2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton2ActionPerformed(evt);
}
});
getContentPane().add(jButton2);
jButton2.setBounds(190, 40, 160, 23);
jTable1.setModel(new javax.swing.table.DefaultTableModel(
new Object [][] {
},
new String [] {
"ONLINE"
}
) {
Class[] types = new Class [] {
java.lang.String.class
};
boolean[] canEdit = new boolean [] {
false
};
public Class getColumnClass(int columnIndex) {
return types [columnIndex];
}
public boolean isCellEditable(int rowIndex, int columnIndex) {
return canEdit [columnIndex];
}
});
jScrollPane2.setViewportView(jTable1);
if (jTable1.getColumnModel().getColumnCount() > 0) {
jTable1.getColumnModel().getColumn(0).setResizable(false);
}
getContentPane().add(jScrollPane2);
jScrollPane2.setBounds(400, 70, 100, 500);
pack();
}// </editor-fold>//GEN-END:initComponents
private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jTextField1ActionPerformed
// TODO add your handling code here:
}//GEN-LAST:event_jTextField1ActionPerformed
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton2ActionPerformed
if (jButton2.getText().equals("VIEW ONLINE USER")) {
// jTable1.setVisible(true);
setSize(500, 600);
jButton2.setText("HIDE ONLINE USER");
} else {
// jTable1.setVisible(false);
jButton2.setText("VIEW ONLINE USER");
setSize(406, 600);
}
// TODO add your handling code here:
}//GEN-LAST:event_jButton2ActionPerformed
public void run() throws IOException {
Socket socket = new Socket("127.0.0.1", 9001);
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
out = new PrintWriter(socket.getOutputStream(), true);
while (true) {
String username = "abc";
//jLabel2.getText().toString();
String line = in.readLine();
if (line.startsWith("GETNAME")) {
out.println(username);
}
if (line.startsWith("MESSAGE ")) {
String msg = line.substring(8);
jTextArea1.append(msg + "\n");
}
}
}
/**
* @param args the command line arguments
* @throws java.io.IOException
*/
// public static void main (String[] args) throws IOException{
public static void main(String[] args) throws IOException {
ChatClientGuiTEST client = new ChatClientGuiTEST();
// client.setVisible(true);
client.run();
}
// Variables declaration - do not modify//GEN-BEGIN:variables
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JScrollPane jScrollPane2;
private javax.swing.JTable jTable1;
private javax.swing.JTextArea jTextArea1;
private javax.swing.JTextField jTextField1;
// End of variables declaration//GEN-END:variables
}
ChatServerGui.java
package chating;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.sql.*;
import java.util.HashSet;
import javax.swing.JOptionPane;
public class ChatServerGui {
ResultSet rs;
private static final int PORT = 9001;
private static HashSet<PrintWriter> writers = new HashSet<PrintWriter>();
public static void main(String[] args) throws Exception {
System.out.println("The chat server is running.");
ServerSocket listener = new ServerSocket(PORT);
try {
while (true) {
new Handler(listener.accept()).start();
}
} finally {
listener.close();
}
}
// public static void startServer()throws IOException{
// System.out.println("The chat server is running.");
// ServerSocket listener = new ServerSocket(PORT);
// try {
// while (true) {
// new Handler(listener.accept()).start();
//
// }
// } finally {
// listener.close();
// }
// }
void setVisible(boolean b) {
throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
}
private static class Handler extends Thread {
private Socket socket;
private BufferedReader in;
private PrintWriter out;
public Handler(Socket socket) {
this.socket = socket;
}
public void run() {
try {
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
out = new PrintWriter(socket.getOutputStream(), true);
writers.add(out);
while (true) {
out.println("GETNAME");
String name = in.readLine();
String input = in.readLine();
if (input == null) {
return;
}
try{
connection obj = new connection();
String query="INSERT INTO tb_msg (msg) VALUES('"+input+"')";
connection.pst = connection.con.prepareStatement(query);
int rst = connection.pst.executeUpdate();
}
catch(Exception e){
JOptionPane.showMessageDialog(null,"ERROR THERE MIGHT BE PROBLEM IN DATABASE","ERROR",0);
}
for (PrintWriter writer : writers) {
writer.println("MESSAGE "+name +":"+ input);
}
}
} catch (IOException e) {
System.out.println(e);
}
// finally {
//
// if (out != null) {
// writers.remove(out);
// }
try {
socket.close();
} catch (IOException e) {
}
}
}
}
//}
1楼
我在这里大胆猜测。 在服务器文件中，您在while true循环中创建了大量线程。 由于它们是分离的线程，因此主线程的执行不会停止，因此您基本上是在填充JVM内存。
while (true) {
new Handler(listener.accept()).start();
}
您没有收到OOM错误的原因是因为线程在启动时就结束了，原因是：
while (true) {
out.println("GETNAME");
String name = in.readLine();
String input = in.readLine();
if (input == null) {
return; // <-- Ends the while loop and the run function, thread dies
}
// ...
您应该使用continue而不是return来跳过其余的循环代码。
但是，如果这样做，您的JVM将立即爆炸！
您真的需要大量的Handler吗？
还有一些connection和PreparedStatement实例未正确关闭，我不确定每次收到消息时都创建新的连接是可行的方法。