enkeyz
Reputation: 43
Java multithreading in JFrame
I want this code work with update JProgressBar and JTextArea while scanner is working, but I don't know how implement Threading. Is it possible?
This is my code:
UPDATED: It's a working version now, with "Stop" function. I added a "breakPoint" variable to break out from the for loop.
package main;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.UnknownHostException;
import javax.swing.JOptionPane;
import javax.swing.SwingWorker;
public class PortScanner extends javax.swing.JFrame {
private doSomeStuff taskPortScanner;
private boolean breakPoint;
public PortScanner() {
initComponents();
}
private void portScan() {
int currentPort = 1;
try {
String hostname = hostNameTextField.getText();
int timeOut = (Integer) timeOutSpinner.getValue();
int minPort = Integer.parseInt(portMinTextField.getText());
int maxPort = Integer.parseInt(portMaxTextField.getText());
//set min and max value of progress bar
jProgressBar1.setMinimum(minPort);
jProgressBar1.setMaximum(maxPort);
//print out the address
InetAddress theAddress = InetAddress.getByName(hostname);
resultTextArea.append("IP adress: " + theAddress + "\n\n");
//check if port is open
for (currentPort = minPort; currentPort <= maxPort; currentPort++) {
//stop for loop
if (breakPoint == true) {
System.out.println("Portscanning stopped.");
break;
}
try {
Socket socket = new Socket();
socket.connect(new InetSocketAddress(hostname, currentPort), timeOut);
//update textarea
resultTextArea.append("Service running on port " + currentPort + "\n");
socket.close();
} catch (Exception ex) {
System.out.println(currentPort);
}
//update progressbar
jProgressBar1.setValue(currentPort);
jProgressBar1.repaint();
}
} catch (UnknownHostException ex) {
JOptionPane.showMessageDialog(PortScanner.this, "Unknown hostname: " + ex.getMessage(), "Error", JOptionPane.ERROR_MESSAGE);
} catch (NumberFormatException ex) {
JOptionPane.showMessageDialog(PortScanner.this, "Invalid format. " + ex.getMessage(), "Error", JOptionPane.ERROR_MESSAGE);
} catch (Exception ex) {
JOptionPane.showMessageDialog(PortScanner.this, "Error: " + ex.getMessage(), "Error", JOptionPane.ERROR_MESSAGE);
}
}
private class doSomeStuff extends SwingWorker<Void, Void> {
@Override
public Void doInBackground() throws Exception {
portScan();
return null;
}
@Override
public void done() {
//if thread is done enable start and clear buttons
clearButton.setEnabled(true);
startButton.setEnabled(true);
}
}
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jLabel1 = new javax.swing.JLabel();
jLabel2 = new javax.swing.JLabel();
jLabel3 = new javax.swing.JLabel();
hostNameTextField = new javax.swing.JTextField();
portMinTextField = new javax.swing.JTextField();
jScrollPane1 = new javax.swing.JScrollPane();
resultTextArea = new javax.swing.JTextArea();
startButton = new javax.swing.JButton();
clearButton = new javax.swing.JButton();
portMaxTextField = new javax.swing.JTextField();
jProgressBar1 = new javax.swing.JProgressBar();
timeOutSpinner = new javax.swing.JSpinner();
jLabel4 = new javax.swing.JLabel();
stopButton = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("Simple port scanner");
setResizable(false);
jLabel1.setText("Hostname");
jLabel2.setText("Timeout");
jLabel3.setText("Port range");
hostNameTextField.setToolTipText("Type a hostname like www.google.com");
portMinTextField.setText("1");
resultTextArea.setColumns(20);
resultTextArea.setRows(5);
jScrollPane1.setViewportView(resultTextArea);
startButton.setText("Scan");
startButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
startButtonActionPerformed(evt);
}
});
clearButton.setText("Clear");
clearButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
clearButtonActionPerformed(evt);
}
});
portMaxTextField.setText("1000");
jProgressBar1.setStringPainted(true);
timeOutSpinner.setModel(new javax.swing.SpinnerNumberModel(15, 0, 999999, 1));
jLabel4.setText("-");
stopButton.setText("Stop");
stopButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
stopButtonActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jLabel2)
.addComponent(jLabel1))
.addGap(21, 21, 21)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(hostNameTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 112, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(layout.createSequentialGroup()
.addComponent(timeOutSpinner)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))))
.addGroup(layout.createSequentialGroup()
.addComponent(jLabel3)
.addGap(18, 18, 18)
.addComponent(portMinTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 62, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(jLabel4)
.addGap(12, 12, 12)
.addComponent(portMaxTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 62, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addGap(0, 0, Short.MAX_VALUE))
.addComponent(jScrollPane1, javax.swing.GroupLayout.Alignment.TRAILING)
.addComponent(jProgressBar1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
.addContainerGap())
.addGroup(layout.createSequentialGroup()
.addGap(30, 30, 30)
.addComponent(startButton)
.addGap(18, 18, 18)
.addComponent(stopButton)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 46, Short.MAX_VALUE)
.addComponent(clearButton)
.addGap(32, 32, 32))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel1)
.addComponent(hostNameTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel2)
.addComponent(timeOutSpinner, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel3)
.addComponent(portMinTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(portMaxTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jLabel4))
.addGap(18, 18, 18)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 157, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(jProgressBar1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 23, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(startButton)
.addComponent(clearButton)
.addComponent(stopButton))
.addContainerGap())
);
pack();
}// </editor-fold>
private void startButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
breakPoint = false;
taskPortScanner = new doSomeStuff();
taskPortScanner.execute();
startButton.setEnabled(false);
clearButton.setEnabled(false);
System.out.println("Starting portscanner...");
}
private void clearButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
resultTextArea.setText(null);
jProgressBar1.setValue(0);
System.out.println("Clearing results...");
}
private void stopButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
breakPoint = true;
startButton.setEnabled(true);
clearButton.setEnabled(true);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(PortScanner.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(PortScanner.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(PortScanner.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(PortScanner.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new PortScanner().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton clearButton;
private javax.swing.JTextField hostNameTextField;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel4;
private javax.swing.JProgressBar jProgressBar1;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTextField portMaxTextField;
private javax.swing.JTextField portMinTextField;
private javax.swing.JTextArea resultTextArea;
private javax.swing.JButton startButton;
private javax.swing.JButton stopButton;
private javax.swing.JSpinner timeOutSpinner;
// End of variables declaration
}
Upvotes: 2
Views: 492
Answers (1)
Alan Hay
Reputation: 23226
You need to look at moving the long running scan task out of the Event dispatching thread to keep the UI responsive. Look at using a Swing Worker to achieve this.
http://en.wikipedia.org/wiki/SwingWorker#The_event_dispatching_thread_problem
http://docs.oracle.com/javase/tutorial/uiswing/concurrency/worker.html
Upvotes: 3