How to really close a JDialog with Java code?
I know setVisible(false),dispose(),but they can't really close a JDialog. When I have the other thread stop, the thread of the JDialog still runs.
And I can't use System.exit(0),because the other thread needs run for a while.
Following the code, I finally resolve the problem by System.exit(0) at the end of the program.
public class CsUpdateCtrl {
/**
* 升级service
*/
private CsUpdateService service;
private CsUpdateCtrl() {
this.service = (CsUpdateService) RmiUtil.getBean(RmiUtil.Service.csupdate);
}
private static final Logger log = Logger.getLogger(CsUpdateCtrl.class.getName());
public static void main(String[] args) throws IOException {
LogUtil.read();
log.info("进入自动更新系统");
CsUpdateCtrl ctrl = null;
try {
ctrl = new CsUpdateCtrl();
} catch (Exception e) {
SwingUtil.lookAndFeel();
SwingUtil.message("无法连接服务器!");
log.info("无法连接服务器:" + e.getMessage());
return;
}
ctrl.start(ctrl.service.version());
}
/**
* 根据版本号判断是否更新，更新完毕则启动程序
*/
private void start(int version) {
PropertyIO io = new PropertyIO();
String oldVersion = io.get(PropertyKey.version);
String serverAddress = io.get(PropertyKey.serverAddress);
if (oldVersion == null || !oldVersion.equals(String.valueOf(version))) {// 版本号不相等,下载更新程序
log.info("下载更新…");
DownLoad download1 = new DownLoad("http://" + serverAddress + "sdxg-csupdate/sdxg-csclient/sdxg-csclient.jar", "sdxg-csclient\\sdxg-csclient.jar");
Thread t1 = new Thread(download1);
DownLoad download2 = new DownLoad("http://" + serverAddress + "sdxg-csupdate/sdxg-csclient/lib/sdxg-web.jar", "sdxg-csclient\\lib\\sdxg-web.jar");
Thread t2 = new Thread(download2);
t1.start();
t2.start();
SwingUtil.lookAndFeel();
final DownloadView dialog = new DownloadView(new javax.swing.JFrame(), true);
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
dialog.setVisible(true);
}
});
// 结果判断
// 若未完成,则不进行下一步
while(!download1.result.finish() || !download2.result.finish()) {
// do nothing
}
if(download1.result == Result.Complete && download2.result == Result.Complete) {// 更新完成
// 版本号写入配置文件
io.write(PropertyKey.version, String.valueOf(version));
// Nothing is usefull here, include dispose,dispatchEvent and so on
// 启用应用程序
log.info("启用应用程序");
this.runApp();
System.exit(0);// well, this is usefull
} else {// 更新失败
// Nothing is usefull here, include dispose,dispatchEvent and so on
JOptionPane.showMessageDialog(null, "下载应用程序失败!");
log.info("下载应用程序失败!");
System.exit(0);// well, this is usefull
}
}else {// 版本号一样
log.info("启用应用程序");
this.runApp();
}
}
/**
* 运行客户端程序
*/
private void runApp() {
try {
Runtime.getRuntime().exec("java -jar " + "sdxg-csclient\\sdxg-csclient.jar");
} catch (IOException ex) {
JOptionPane.showMessageDialog(null, "启动应用程序失败!");
log.info(LogUtil.ex(ex, "启动应用程序失败!"));
}
}
/**
* 线程执行的结果
*/
enum Result {
Complete,
UnComplete,
Fail;
public boolean finish() {
return this != UnComplete;
}
}
/**
* 下载文件
* @param urlName
* @param fileName
* @throws MalformedURLException
* @throws IOException
*/
class DownLoad implements Runnable {
private String urlName;
private String fileName;
Result result = Result.UnComplete;
public DownLoad(String urlName, String fileName) {
this.urlName = urlName;
this.fileName = fileName;
}
@Override
public void run() {
try {
URL url = new URL(urlName);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
InputStream is = connection.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
FileOutputStream fos = new FileOutputStream(fileName);
int n = -1;
while ((n = bis.read()) != -1) {
fos.write(n);
}
fos.flush();
fos.close();
bis.close();
is.close();
result = Result.Complete;
} catch (Exception ex) {
result = Result.Fail;
}
}
}
Answer
Send the JDialog a WindowEvent.WINDOW_CLOSING event using dispatchEvent(), as shown here and here.
Addendum: System.exit() should be used with care, as discussed here and here. In the example below, a second, non-daemon thread completes normally, even if the dialog is closed before its loop exits. See JLS §12.8 Program Exit for details.
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JLabel;
/**
* @see https://stackoverflow.com/questions/8336161
* @see https://stackoverflow.com/questions/6163606
*/
public class DialogEventTest extends JDialog {
public DialogEventTest() {
this.setLayout(new GridLayout(0, 1));
this.add(new JLabel("Dialog event test.", JLabel.CENTER));
this.add(new JButton(new AbstractAction("Close") {
@Override
public void actionPerformed(ActionEvent e) {
DialogEventTest.this.setVisible(false);
DialogEventTest.this.dispatchEvent(new WindowEvent(
DialogEventTest.this, WindowEvent.WINDOW_CLOSING));
}
}));
this.addWindowListener(new WindowAdapter() {
@Override
public void windowClosing(WindowEvent e) {
System.out.println(e.paramString());
}
});
}
private void display() {
this.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
this.pack();
this.setLocationRelativeTo(null);
this.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new DialogEventTest().display();
}
});
new Thread(new Runnable() {
@Override
public void run() {
System.out.println("Starting…");
for (int i = 0; i < 5; i++) {
try {
Thread.sleep(1000);
System.out.println((i + 1) + "s. elapsed.");
} catch (InterruptedException e) {
e.printStackTrace(System.err);
}
}
System.out.println("Finished.");
}
}).start();
}
}