Warning: file_get_contents(/data/phpspider/zhask/data//catemap/6/rest/5.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
为什么程序在java中即使出现异常也不会终止?_Java_Swing_Exception_Arithmeticexception - Fatal编程技术网

为什么程序在java中即使出现异常也不会终止?

为什么程序在java中即使出现异常也不会终止?,java,swing,exception,arithmeticexception,Java,Swing,Exception,Arithmeticexception,我刚刚使用Netbeans GUI Builder(我是Java新手)创建了一个简单的JFrame表单,它执行两个整数的除法,如下所示: 这里我尝试将2除以0 显然,我得到了一个算术异常 以下是表格的代码: public class division extends javax.swing.JFrame { public division() { initComponents(); } @SuppressWarnings("unchecked")

我刚刚使用Netbeans GUI Builder(我是Java新手)创建了一个简单的
JFrame
表单,它执行两个整数的除法,如下所示:

这里我尝试将2除以0

显然,我得到了一个算术异常

以下是表格的代码:

public class division extends javax.swing.JFrame {

    public division() {
        initComponents();
    }

    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        t1 = new javax.swing.JTextField();
        jLabel1 = new javax.swing.JLabel();
        t2 = new javax.swing.JTextField();
        l2 = new javax.swing.JLabel();
        jButton1 = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        getContentPane().setLayout(null);
        getContentPane().add(t1);
        t1.setBounds(49, 60, 51, 20);

        jLabel1.setText("/");
        getContentPane().add(jLabel1);
        jLabel1.setBounds(110, 63, 4, 14);
        getContentPane().add(t2);
        t2.setBounds(118, 60, 50, 20);

        l2.setText("=");
        getContentPane().add(l2);
        l2.setBounds(172, 63, 8, 14);

        jButton1.setText("Divide");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        });
        getContentPane().add(jButton1);
        jButton1.setBounds(78, 109, 61, 23);

        pack();
    }// </editor-fold>                        

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
        int a=Integer.parseInt(t1.getText());
        int b=Integer.parseInt(t2.getText());

        int c=a/b;

        l2.setText("="+c);
    }                                        

    /**
     * @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(division.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(division.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(division.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(division.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 division().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel l2;
    private javax.swing.JTextField t1;
    private javax.swing.JTextField t2;
    // End of variables declaration                   
}
我有一个简单的疑问。即使抛出
异常
,我的程序仍会继续运行。
另一方面,我认为如果您不捕获异常,它将终止您的程序。

为什么它会继续运行?我错在哪里?

所有Java swing应用程序都运行在独立于主线程的独立内部线程上。api中发生的任何事件(按下按钮、从下拉框中选择项目、在文本字段中输入文本等)都会作为消息添加到swings内部事件que,该事件稍后会被swings内部线程删除并处理。这些消息彼此独立,因此处理它们时发生的任何异常都不会影响应用程序。如果你真的想终止你的应用程序,你必须用系统终止主线程。退出(0)@RVISHAL谢谢!我有了基本的想法。如果你能推荐一些资源来进一步研究这一点,那将非常有帮助。Java GUI必须在不同的操作系统、屏幕大小、屏幕分辨率等方面工作,在不同的地区使用不同的PLAF。因此,它们不利于像素完美布局。而是使用布局管理器,或与布局填充和边框一起使用。
Exception in thread "AWT-EventQueue-0" java.lang.ArithmeticException: / by zero 
    at division.jButton1ActionPerformed(division.java:90)
    at division.access$000(division.java:11)
    at division$1.actionPerformed(division.java:44)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2341)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
    at java.awt.Component.processMouseEvent(Component.java:6505)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3320)
    at java.awt.Component.processEvent(Component.java:6270)
    at java.awt.Container.processEvent(Container.java:2229)
    at java.awt.Component.dispatchEventImpl(Component.java:4861)
    at java.awt.Container.dispatchEventImpl(Container.java:2287)
    at java.awt.Component.dispatchEvent(Component.java:4687)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4832)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4492)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4422)
    at java.awt.Container.dispatchEventImpl(Container.java:2273)
    at java.awt.Window.dispatchEventImpl(Window.java:2719)
    at java.awt.Component.dispatchEvent(Component.java:4687)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:735)
    at java.awt.EventQueue.access$200(EventQueue.java:103)
    at java.awt.EventQueue$3.run(EventQueue.java:694)
    at java.awt.EventQueue$3.run(EventQueue.java:692)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:87)
    at java.awt.EventQueue$4.run(EventQueue.java:708)
    at java.awt.EventQueue$4.run(EventQueue.java:706)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:705)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)