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java按钮java中出现空指针异常错误_Java_User Interface_Nullpointerexception_Azure Database Mysql - Fatal编程技术网

java按钮java中出现空指针异常错误

java按钮java中出现空指针异常错误,java,user-interface,nullpointerexception,azure-database-mysql,Java,User Interface,Nullpointerexception,Azure Database Mysql,每次我尝试输入电子邮件密码和名称的详细信息时,按钮上就会出现空指针异常 但是,数据库中的所有内容都是有效的,并且连接也已建立,但在我按下addaccounter按钮后,它会给出错误 我试图检查我的数据库连接代码,一切正常,我的连接变量也已初始化 private void addbtn2ActionPerformed(java.awt.event.ActionEvent evt) { try {

每次我尝试输入电子邮件密码和名称的详细信息时,按钮上就会出现空指针异常

但是,数据库中的所有内容都是有效的,并且连接也已建立,但在我按下addaccounter按钮后,它会给出错误

我试图检查我的数据库连接代码,一切正常,我的连接变量也已初始化

private void addbtn2ActionPerformed(java.awt.event.ActionEvent evt) {                                        

    try {


        PreparedStatement stmt = con.prepareStatement("INSERT INTO accountant('email','password','name')VALUES(?,?,?)");

        String names=namef2.getText();
        String emails=emailf2.getText();
        String passwords=String.valueOf(jPasswordField2.getText());
        String c_p=String.valueOf(jPasswordField2.getText());
        stmt.setString(1, emails);
        stmt.setString(2, passwords);
        stmt.setString(3, names);
        JOptionPane.showMessageDialog(null,"Accountant Successfully added");
        stmt.execute();
        stmt.close();

    } catch (SQLException ex) {
        Logger.getLogger(AccountantDetails.class.getName()).log(Level.SEVERE, null, ex);
    }
}    
输出

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at Admin.panel.AccountantDetails.addbtn2ActionPerformed(AccountantDetails.java:300)
at Admin.panel.AccountantDetails.access$300(AccountantDetails.java:15)
at Admin.panel.AccountantDetails$4.actionPerformed(AccountantDetails.java:186)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
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:6539)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
at java.awt.Component.processEvent(Component.java:6304)
at java.awt.Container.processEvent(Container.java:2239)
at java.awt.Component.dispatchEventImpl(Component.java:4889)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4904)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4535)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4476)
at java.awt.Container.dispatchEventImpl(Container.java:2283)
at java.awt.Window.dispatchEventImpl(Window.java:2746)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84)
at java.awt.EventQueue$4.run(EventQueue.java:733)
at java.awt.EventQueue$4.run(EventQueue.java:731)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

BUILD SUCCESSFUL (total time: 11 seconds)

如果这是按钮单击操作

私有void addbtn2ActionPerformed(java.awt.event.ActionEvent evt){


那么参数应该是View,而不是ActionEvent。

尝试设置问题的格式。一半的代码是纯文本…先生,我不明白。如果我弄错了,你能给我整个命令吗