Java simultaneous execution - java

I am trying execute two jobs simultaneously. One of the things that I am trying to do is displaying a count up timer and the other one is moving the ball.
This is where I create the timer and also call the moveBall method
button.addChangeListener(new ChangeListener() {
int start = 0;
public void stateChanged(ChangeEvent e) {
ActionListener taskPerformer = new ActionListener() {
public void actionPerformed(ActionEvent evt) {
timeValue.setText(++start + " sec");
}
};
timer = new Timer(1000, taskPerformer);
timer.start();
ball.moveBall();
}
});
This is my moveBall method
public void moveBall() {
Thread ball = new Thread() {
double counter = 0;
int t = (int) (2 * Vy / 9.8);
public void run() {
try {
while (t >= 0) {
// calculate Vx and Vy
Ball.this.setX(Ball.this.getX() + Vx);
Ball.this.setY(Ball.this.getY() - Vy);
counter += 50;
if (counter == 1000) {
t--;
counter = 0;
}
paintingComponent.repaint();
Thread.sleep(20);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
ball.start();
}
When I execute the above code the label for displaying the time passed is not changing at all during the ball is moving and when the movement is over it takes the last number that it supposed to take.

This is a example two executions of two threads, Java simultaneous execution
public class ThreadExecutor extends Thread {
private String name;
private int executionCount;
public ThreadExecutor(final String name, final int executionCount) {
this.name = name;
this.executionCount = executionCount;
}
#Override
public void run() {
int count = 1;
while (count <= executionCount) {
System.out.println("Executing thread ".concat(name).concat(" : ") + count);
count++;
}
}
}
public class Main {
public static void main(String args[]) {
final ThreadExecutor one = new ThreadExecutor("One", 1);
final ThreadExecutor two = new ThreadExecutor("Two", 2);
one.start();
two.start();
}
}

Related

JFrame freezes when button is pressed and operations from the other Class are ran [duplicate]

I'm writing a program that constantly pings a server. I wrote the code to check it once and put the ping in a JLabel and put it in a method called setPing().
Here is my code
private void formWindowOpened(java.awt.event.WindowEvent evt) {
setPing();
}
That worked but only did it once, so I did:
private void formWindowOpened(java.awt.event.WindowEvent evt) {
for(;;){
setPing();
}
}
But this doesn't even work for the first time.
I didnt put the setPing method because it was too long so here it is:
public String setPing(){
Runtime runtime = Runtime.getRuntime();
try{
Process process = runtime.exec("ping lol.garena.com");
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
int i = 0;
i = line.indexOf("Average");
if(i > 0){
String finalPing = "";
line.toCharArray();
try
{
finalPing = "";
for(int x = i; x < i + 17; x++)
{
finalPing = finalPing + (line.charAt(x));
}
}catch(IndexOutOfBoundsException e)
{
try
{
finalPing = "";
for(int x = i; x < i + 16; x++)
{
finalPing = finalPing + (line.charAt(x));
}
}catch(IndexOutOfBoundsException f)
{
try
{
finalPing = "";
for(int x = i; x < i + 15; x++)
{
finalPing = finalPing + (line.charAt(x));
}
}catch(IndexOutOfBoundsException g){}
}
}
String final1Ping = finalPing.replaceAll("[^0-9]", "");
return final1Ping;
}
}
}catch(IOException e){
}
return "";
}
UPDATE
Just in case this is important, Im using netbeans. I created a form and put this code in the formWindowOpened evt instead of calling it in main:
private void formWindowOpened(java.awt.event.WindowEvent evt) {
ActionListener timerListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
new PingWorker().execute();
}
};
Timer timer = new Timer(1000, timerListener);
timer.start();
jLabel1.setText(label.getText());
timer.stop();
// TODO add your handling code here:
}
class PingWorker extends SwingWorker {
int time;
#Override
protected Object doInBackground() throws Exception {
time = pingTime("lol.garena.com");
return new Integer(time);
}
#Override
protected void done() {
label.setText("" + time);
}
};
public JComponent getUI() {
return label;
}
public static int pingTime(String hostnameOrIP) {
Socket socket = null;
long start = System.currentTimeMillis();
try {
socket = new Socket(hostnameOrIP, 80);
} catch (IOException ex) {
ex.printStackTrace();
} finally {
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
}
}
}
long end = System.currentTimeMillis();
return (int) (end - start);
}
Use a Swing Timer for repeating tasks & a SwingWorker for long running tasks. E.G. of both below - it uses a Timer to repeatedly perform a 'long running' task (a ping) in a SwingWorker.
See Concurrency in Swing for more details on the Event Dispatch Thread and doing long running or repeating tasks in a GUI.
This code combines a long running task ('pinging' a server) using SwingWorker invoked from a repeating task (updating the JLabel repeatedly with the times) using a Swing based Timer.
import java.awt.event.*;
import javax.swing.*;
import java.net.Socket;
public class LabelUpdateUsingTimer {
static String hostnameOrIP = "stackoverflow.com";
int delay = 5000;
JLabel label = new JLabel("0000");
LabelUpdateUsingTimer() {
label.setFont(label.getFont().deriveFont(120f));
ActionListener timerListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
new PingWorker().execute();
}
};
Timer timer = new Timer(delay, timerListener);
timer.start();
JOptionPane.showMessageDialog(
null, label, hostnameOrIP, JOptionPane.INFORMATION_MESSAGE);
timer.stop();
}
class PingWorker extends SwingWorker {
int time;
#Override
protected Object doInBackground() throws Exception {
time = pingTime();
return new Integer(time);
}
#Override
protected void done() {
label.setText("" + time);
}
};
public static int pingTime() {
Socket socket = null;
long start = System.currentTimeMillis();
try {
socket = new Socket(hostnameOrIP, 80);
} catch (Exception weTried) {
} finally {
if (socket != null) {
try {
socket.close();
} catch (Exception weTried) {}
}
}
long end = System.currentTimeMillis();
return (int) (end - start);
}
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
new LabelUpdateUsingTimer();
}
};
SwingUtilities.invokeLater(r);
}
}
You could use a Thread. The problem is you are blocking the main thread, thereby blocking your program. To get around this, start a background Thread to update components repeatedly.
(Note: you need to update GUI components on the EDT, so use SwingUtilities.invokeLater)
(new Thread((new Runnable(){
#Override
public void run(){
while(true){
SwingUtilities.invokeLater(new Runnable(){
#Override
public void run(){
refToJLabel.setText(Math.random());
}
});
}
}
}))).start();

Following method call prevents JLabel from getting visible [duplicate]

I'm writing a program that constantly pings a server. I wrote the code to check it once and put the ping in a JLabel and put it in a method called setPing().
Here is my code
private void formWindowOpened(java.awt.event.WindowEvent evt) {
setPing();
}
That worked but only did it once, so I did:
private void formWindowOpened(java.awt.event.WindowEvent evt) {
for(;;){
setPing();
}
}
But this doesn't even work for the first time.
I didnt put the setPing method because it was too long so here it is:
public String setPing(){
Runtime runtime = Runtime.getRuntime();
try{
Process process = runtime.exec("ping lol.garena.com");
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
int i = 0;
i = line.indexOf("Average");
if(i > 0){
String finalPing = "";
line.toCharArray();
try
{
finalPing = "";
for(int x = i; x < i + 17; x++)
{
finalPing = finalPing + (line.charAt(x));
}
}catch(IndexOutOfBoundsException e)
{
try
{
finalPing = "";
for(int x = i; x < i + 16; x++)
{
finalPing = finalPing + (line.charAt(x));
}
}catch(IndexOutOfBoundsException f)
{
try
{
finalPing = "";
for(int x = i; x < i + 15; x++)
{
finalPing = finalPing + (line.charAt(x));
}
}catch(IndexOutOfBoundsException g){}
}
}
String final1Ping = finalPing.replaceAll("[^0-9]", "");
return final1Ping;
}
}
}catch(IOException e){
}
return "";
}
UPDATE
Just in case this is important, Im using netbeans. I created a form and put this code in the formWindowOpened evt instead of calling it in main:
private void formWindowOpened(java.awt.event.WindowEvent evt) {
ActionListener timerListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
new PingWorker().execute();
}
};
Timer timer = new Timer(1000, timerListener);
timer.start();
jLabel1.setText(label.getText());
timer.stop();
// TODO add your handling code here:
}
class PingWorker extends SwingWorker {
int time;
#Override
protected Object doInBackground() throws Exception {
time = pingTime("lol.garena.com");
return new Integer(time);
}
#Override
protected void done() {
label.setText("" + time);
}
};
public JComponent getUI() {
return label;
}
public static int pingTime(String hostnameOrIP) {
Socket socket = null;
long start = System.currentTimeMillis();
try {
socket = new Socket(hostnameOrIP, 80);
} catch (IOException ex) {
ex.printStackTrace();
} finally {
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
}
}
}
long end = System.currentTimeMillis();
return (int) (end - start);
}
Use a Swing Timer for repeating tasks & a SwingWorker for long running tasks. E.G. of both below - it uses a Timer to repeatedly perform a 'long running' task (a ping) in a SwingWorker.
See Concurrency in Swing for more details on the Event Dispatch Thread and doing long running or repeating tasks in a GUI.
This code combines a long running task ('pinging' a server) using SwingWorker invoked from a repeating task (updating the JLabel repeatedly with the times) using a Swing based Timer.
import java.awt.event.*;
import javax.swing.*;
import java.net.Socket;
public class LabelUpdateUsingTimer {
static String hostnameOrIP = "stackoverflow.com";
int delay = 5000;
JLabel label = new JLabel("0000");
LabelUpdateUsingTimer() {
label.setFont(label.getFont().deriveFont(120f));
ActionListener timerListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
new PingWorker().execute();
}
};
Timer timer = new Timer(delay, timerListener);
timer.start();
JOptionPane.showMessageDialog(
null, label, hostnameOrIP, JOptionPane.INFORMATION_MESSAGE);
timer.stop();
}
class PingWorker extends SwingWorker {
int time;
#Override
protected Object doInBackground() throws Exception {
time = pingTime();
return new Integer(time);
}
#Override
protected void done() {
label.setText("" + time);
}
};
public static int pingTime() {
Socket socket = null;
long start = System.currentTimeMillis();
try {
socket = new Socket(hostnameOrIP, 80);
} catch (Exception weTried) {
} finally {
if (socket != null) {
try {
socket.close();
} catch (Exception weTried) {}
}
}
long end = System.currentTimeMillis();
return (int) (end - start);
}
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
new LabelUpdateUsingTimer();
}
};
SwingUtilities.invokeLater(r);
}
}
You could use a Thread. The problem is you are blocking the main thread, thereby blocking your program. To get around this, start a background Thread to update components repeatedly.
(Note: you need to update GUI components on the EDT, so use SwingUtilities.invokeLater)
(new Thread((new Runnable(){
#Override
public void run(){
while(true){
SwingUtilities.invokeLater(new Runnable(){
#Override
public void run(){
refToJLabel.setText(Math.random());
}
});
}
}
}))).start();

Opening a new JFrame using a JButton

I have two classes (Sampling and Stacker). The Sampling class (my Main class) is extends JFrame and has a JButton with an ActionListener to open the Stacker class.
The problem is when the button is clicked, the Stacker class will open but only a frame without any components. When I switch the main method into the Stacker class, the program works fine. What is the problem?
Here is the code:
The Sampling class:
public class Sampling extends JFrame implements ActionListener
{
private JButton openStacker;
Stacker st;
public Sampling()
{
setSize(300,300);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLayout(new FlowLayout());
setLocationRelativeTo(null);
openStacker = new JButton("Start Stacker!");
add(openStacker);
openStacker.addActionListener(this);
setVisible(true);
}
public void actionPerformed(ActionEvent e)
{
dispose();
st = new Stacker();
}
public static void main (String args[])
{
new Sampling();
}
}
The Stacker game class:
public class Stacker extends JFrame implements KeyListener
{
int iteration = 1;
double time = 200;
int last = 0;
int m = 10;
int n = 20;
JButton b[][];
int length[] = {5,5};
int layer = 19;
int deltax[] = {0,0};
boolean press = false;
boolean forward = true;
boolean start = true;
public Stacker()
{
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setSize(400,580);
this.setUndecorated(false);
this.setLocationRelativeTo(null);
b = new JButton [m][n];
setLayout(new GridLayout(n,m));
for (int y = 0;y<n;y++)
{
for (int x = 0;x<m;x++)
{
b[x][y] = new JButton(" ");
b[x][y].setBackground(Color.DARK_GRAY);
add(b[x][y]);
b[x][y].setEnabled(false);
}//end inner for
}
this.setFocusable(true);
this.pack();
this.addKeyListener(this);
this.setVisible(true);
go();
}
public void go()
{
int tmp = 0;
Component temporaryLostComponent = null;
do{
if (forward == true)
{
forward();
} else {
back();
}
if (deltax[1] == 10-length[1])
{
forward = false;
} else if (deltax[1] == 0)
{
forward = true;
}
draw();
try
{
Thread.sleep((long) time);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
}while(press == false);
if (layer>12)
{
time= 150-(iteration*iteration*2-iteration);
} else
{
time = time - 2.2;
}
iteration++;
layer--;
press = false;
tmp = check();
length[0] = length[1];
length[1] = tmp;
if (layer == -1)
{
JOptionPane.showMessageDialog(temporaryLostComponent, "Congratulations! You beat the game!");
repeat();
}
if (length[1] <= 0)
{
JOptionPane.showMessageDialog(temporaryLostComponent, "Game over! You reached line "+(18-layer)+"!");
repeat();
}
last = deltax[1];
start = false;
go();
}
public int check()
{
if (start == true)
{
return length[1];
}
else if (last<deltax[1])
{
if (deltax[1]+length[1]-1 <= last+length[0]-1)
{
return length[1];
}
else
{
return length[1]-Math.abs((deltax[1]+length[1])-(last+length[0]));
}
}
else if (last>deltax[1])
{
return length[1]-Math.abs(deltax[1]-last);
}
else
{
return length[1];
}
}
public void forward()
{
deltax[0] = deltax[1];
deltax[1]++;
}
public void back()
{
deltax[0] = deltax[1];
deltax[1]--;
}
public void draw()
{
for (int x = 0;x<length[1];x++)
{
b[x+deltax[0]][layer].setBackground(Color.DARK_GRAY);
}
for (int x = 0;x<length[1];x++)
{
b[x+deltax[1]][layer].setBackground(Color.CYAN);
}
}
public void repeat()
{
if(JOptionPane.showConfirmDialog(null, "PLAY AGAIN?","WARNING",JOptionPane.YES_NO_OPTION)== JOptionPane.YES_OPTION)
{
dispose();
new Stacker();
}else{
System.exit(0);
}
}
public void keyPressed(KeyEvent e)
{
if (e.getKeyCode() == KeyEvent.VK_SPACE)
{
press = true;
}
}
public void keyReleased(KeyEvent arg0)
{
}
public void keyTyped(KeyEvent arg0)
{
}
}
Just to put all my comments into an answer, and give you somewhere to start with:
Comment 1:
Take out go(); see that happens. I tested it and it will work. If you leave it there, even the frame's close button is jammed. You're blocking the edt with the while->Thread.sleep junk. You'll want to do some refactoring. You're code it hard to follow and I have no idea what you're trying to do, so I didn't even attempt it
Comment 2:
If you're wondering why it works when you just run the main from the Stacker class, it's probably because you are running it outside the EDT,
public static void main(String[] args) { new Stacker(); }. What happens when you click the button, that action is performed within the EDT, and hence your new Stacker() will be run on the EDT. In which case the EDT gets blocked by your while loop. If you try run the program from the Stacker class, but wrap it in a SwingUtilities.invokeLater, you will also notice the program fails to work. Swing programs should be run on the EDT though.
Comment 2: Read the first few sections on Concurrency with Swing
So what you can do is use a Swing Timer (which operates on the EDT) for the game loop. What I did was refactor your code a bit. It doesn't operate the way you want it to yet, only because I didn't really understand the logic of your code. So I couldn't get it to work. What I did though, is put some of the logic into the Timer.
Timer timer = new Timer((int)time, new ActionListener(){
public void actionPerformed(ActionEvent event) {
if (forward == true) {
forward();
} else {
back();
}
if (deltax[1] == 10 - length[1]) {
forward = false;
} else if (deltax[1] == 0) {
forward = true;
}
draw();
}
});
And when the go() method is called, it just starts the timer by calling timer.start(). Basically what you need to know about the timer, is that every tick (the milliseconds you pass it), the actionPerformed will be called. So you can update the game state in that method, just like you did in the while loop each iteration.
Take some time to go over How to Use Swing Timers
To get the game working properly, you still need to make some adjustments, but this should give you a head start.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Sampling extends JFrame implements ActionListener {
private JButton openStacker;
Stacker st;
public Sampling() {
setSize(300, 300);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLayout(new FlowLayout());
setLocationRelativeTo(null);
openStacker = new JButton("Start Stacker!");
add(openStacker);
openStacker.addActionListener(this);
setVisible(true);
}
public void actionPerformed(ActionEvent e) {
dispose();
st = new Stacker();
}
public static void main(String args[]) {
SwingUtilities.invokeLater(new Runnable(){
public void run() {
new Sampling();
}
});
}
}
class Stacker extends JFrame implements KeyListener {
int iteration = 1;
double time = 200;
int last = 0;
int m = 10;
int n = 20;
JButton b[][];
int length[] = {5, 5};
int layer = 19;
int deltax[] = {0, 0};
boolean press = false;
boolean forward = true;
boolean start = true;
Timer timer = new Timer((int)time, new ActionListener(){
public void actionPerformed(ActionEvent event) {
if (forward == true) {
forward();
} else {
back();
}
if (deltax[1] == 10 - length[1]) {
forward = false;
} else if (deltax[1] == 0) {
forward = true;
}
draw();
}
});
public Stacker() {
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setSize(400, 580);
this.setUndecorated(false);
this.setLocationRelativeTo(null);
b = new JButton[m][n];
setLayout(new GridLayout(n, m));
for (int y = 0; y < n; y++) {
for (int x = 0; x < m; x++) {
b[x][y] = new JButton(" ");
b[x][y].setBackground(Color.DARK_GRAY);
add(b[x][y]);
b[x][y].setEnabled(false);
}//end inner for
}
this.setFocusable(true);
this.pack();
JPanel panel = (JPanel)getContentPane();
panel.addKeyListener(this);
this.setVisible(true);
panel.requestFocusInWindow();
go();
}
public void go() {
int tmp = 0;
Component temporaryLostComponent = null;
timer.start();
if (layer > 12) {
time = 150 - (iteration * iteration * 2 - iteration);
} else {
time = time - 2.2;
}
iteration++;
layer--;
press = false;
tmp = check();
length[0] = length[1];
length[1] = tmp;
if (layer == -1) {
JOptionPane.showMessageDialog(temporaryLostComponent, "Congratulations! You beat the game!");
repeat();
}
if (length[1] <= 0) {
JOptionPane.showMessageDialog(temporaryLostComponent, "Game over! You reached line " + (18 - layer) + "!");
repeat();
}
last = deltax[1];
start = false;
//go();
}
public int check() {
if (start == true) {
return length[1];
} else if (last < deltax[1]) {
if (deltax[1] + length[1] - 1 <= last + length[0] - 1) {
return length[1];
} else {
return length[1] - Math.abs((deltax[1] + length[1]) - (last + length[0]));
}
} else if (last > deltax[1]) {
return length[1] - Math.abs(deltax[1] - last);
} else {
return length[1];
}
}
public void forward() {
deltax[0] = deltax[1];
deltax[1]++;
}
public void back() {
deltax[0] = deltax[1];
deltax[1]--;
}
public void draw() {
for (int x = 0; x < length[1]; x++) {
b[x + deltax[0]][layer].setBackground(Color.DARK_GRAY);
}
for (int x = 0; x < length[1]; x++) {
b[x + deltax[1]][layer].setBackground(Color.CYAN);
}
}
public void repeat() {
if (JOptionPane.showConfirmDialog(null, "PLAY AGAIN?", "WARNING", JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION) {
dispose();
new Stacker();
} else {
System.exit(0);
}
}
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_SPACE) {
System.out.println("Pressed");
press = true;
}
}
public void keyReleased(KeyEvent arg0) {
}
public void keyTyped(KeyEvent arg0) {
}
}
Notice the SwingUtilities.invokeLater in the main. That's how you can start up the program on the EDT. The link on Concurrency In Swing will give you more information.

Progressbar: how to create deep copy of original object

I'm trying to use a progress bar similar to this one below in Java:
public class MyProgressSplashScreen extends JWindow
{
private final JProgressBar progressbar;
private final ExecutorService autoProgressExecutor = Executors.newFixedThreadPool(1);
public MyProgressSplashScreen(final int theMin, final int theMax)
{
super();
final JPanel contentPanel = new JPanel(new BorderLayout());
contentPanel.setBorder(BorderFactory.createBevelBorder(BevelBorder.RAISED));
if (theMin != -1 && theMax != -1)
{
progressbar = new JProgressBar(SwingConstants.HORIZONTAL, theMin, theMax);
}
else
{
progressbar = new JProgressBar(SwingConstants.HORIZONTAL);
progressbar.setIndeterminate(true);
}
progressbar.setStringPainted(true);
contentPanel.add(progressbar, BorderLayout.SOUTH);
add(contentPanel);
pack();
setAlwaysOnTop(true);
}
public void showProgress(final int theValueTo, final int theEstimatedTimeInSeconds)
{
showProgress(progressbar.getValue(), theValueTo, theEstimatedTimeInSeconds);
}
public void showProgress(final int theValueFrom, final int theValueTo,
final int theEstimatedTimeInSeconds)
{
setVisible(true);
autoProgressExecutor.execute(new Runnable()
{
#Override
public void run()
{
int numberOfSteps = theValueTo - theValueFrom;
long timeToWait = TimeUnit.SECONDS.toMillis(theEstimatedTimeInSeconds)
/ numberOfSteps;
for (int i = theValueFrom; i <= theValueTo; i++)
{
progressbar.setValue(i);
try
{
TimeUnit.MILLISECONDS.sleep(timeToWait);
}
catch (final InterruptedException e) { }
}
if (progressbar.getValue() == 100) { setVisible(false); }
}
});
}
}
I am however not able to pass a copy of the MyProgressSplashScreen in order to let a separate thread update the progress.
For instance the program below starts counting from 0 to 10 and then restarts from 0 to 30 while it shouldn't reset to zero!
public class TestSplashScreen
{
private final MyProgressSplashScreen myProgressSplashScreen = new MyProgressSplashScreen(-1,-1);
public static void main(String args[])
{
TestSplashScreen testInvoke = new TestSplashScreen();
testInvoke.synchronize();
}
public void synchronize()
{
Runnable runnable = new Runnable()
{
#Override
public void run()
{
myProgressSplashScreen.showProgress(10, 2);
myProgressSplashScreen.toFront();
MyRunnable myRunnable = new MyRunnable();
myRunnable.setSyncProgressSplashScreen(myProgressSplashScreen);
Thread t1 = new Thread(myRunnable);
t1.start();
}
};
runnable.run();
}
}
class MyRunnable implements Runnable
{
MyProgressSplashScreen syncProgressSplashScreen;
public void setSyncProgressSplashScreen(MyProgressSplashScreen syncProgressSplashScreen)
{
this.syncProgressSplashScreen = syncProgressSplashScreen;
}
#Override
public void run()
{
syncProgressSplashScreen.showProgress(30, 3);
}
}
The problem is you call syncProgressSplashScreen.showProgress 2 times. The first time it blocks the thread causing it to increment from 0 to 10 then you call it again going from 0 to 30. Remove the line that reads myProgressSplashScreen.showProgress(10, 2); and it wont do it 2 times. Also I noticed you dont set your maximum value for the progress bar so unless you call myProgressSplashScreen.showProgress(100, 2) it wont go to 100%.

Stopping a thread by a swing button

I made a simple program which just tracks the co ordinates of the mouse cursor - it works fine, all I want do is start / stop it with a button.
So far the button starts the thread well, what is the best way which I can safely stop the thread? This is because I may add a facility to write the coordinates to a text file in the future.
Do I make a boolean which makes the thread run only when it is true or something like that? Because I tried to edit the trigger boolean but it had no affect what so ever.
The code as it is :
The class running the thread
public class tester {
static int startTime = (int) System.currentTimeMillis();
static boolean trigger = false;
static JLabel label = new JLabel();
static JLabel status = new JLabel();
static mouseLocate msl = new mouseLocate();
static JButton startButton = new JButton("Begin tracking");
static JButton stopButton = new JButton("Stop Tracker");
static Thread myThread = new Thread(new mouseLocate());
public static void main(String[] args) {
JFrame frame = new JFrame("Mouse Grabber");
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(500, 100);
JPanel panel = new JPanel();
frame.add(panel);
panel.add(startButton);
startButton.addActionListener(new startAction());
panel.add(label);
panel.add(status);
}
static class startAction implements ActionListener {
public void actionPerformed(ActionEvent e) {
try {
if (trigger == false) {
trigger = true;
msl.setTrigger(trigger);
//label.setText("Trigger Active" + msl.isTrigger());
startButton.setText("Continue Tracking");
} else if (trigger == true) {
trigger = false;
//msl.setTrigger(trigger);
label.setText("Trigger Inactive");
startButton.setText("Stop Tracking");
}
} catch (Exception exp) {
System.out.println("EXCEPTION CAUGHT " + e);
}
//RUN
myThread.start();
}
}
The mouse locate class:
public class mouseLocate implements Runnable {
private boolean trigger = false;
private int startTime = (int) System.currentTimeMillis();
static String status = "";
public void run() {
int x, y;
while (mouseGrabber.trigger = true) {
try {
PointerInfo mouseLocation = MouseInfo.getPointerInfo();
x = mouseLocation.getLocation().x;
y = mouseLocation.getLocation().y;
System.out.println("X:" + x + " Y:" + y + " Elapsed time: "
+ (((int) System.currentTimeMillis() - startTime) / 100));
} catch (Exception e) {
System.out.println("Exception caught : " + e);
}
}
}
public int getStartTime() {
return startTime;
}
public void setStartTime(int startTime) {
this.startTime = startTime;
}
public boolean isTrigger() {
return trigger;
}
public void setTrigger(boolean trigger) {
this.trigger = trigger;
}
public static String getStatus() {
return status;
}
public static void setStatus(String status) {
mouseLocate.status = status;
}
}
Thank you for any help I really appreciate it.
There is no stopThread() api on java anymore. You should set a flag as volatile, and your stop thread button just set flag variable value.
public volatile boolean flag;
public void run() {
while(flag) {
// Get coordinate or whatever you want
}
}
public volatile boolean isShutingDown;
public void run() {
while(!isShutingDown) {
}
}
call shutDown() method, when you need to stop
public void shutDown(){
isShutingDown = true
}

Categories