求助~空指针异常问题

2016-09-17 04:09:28 255 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

异常排查 | 重复Cookie访问导致HTTP请求引发空指针异常在IDEA环境下调试排查前端页面，分析服务器受到空指针异常发还HTTP状态码500的原因阅读详情

package com.zky.www.view;

import java.awt.*;



import javax.swing.*;



import com.zky.www.bean.User;

import com.zky.www.dao.Dao;



import java.awt.event.*;

public class UpdatePassIFrame extends JInternalFrame{

	

	private JLabel lbusername=new JLabel("用户名:");

	private JTextField txtusername=new JTextField();

	

	private JLabel lboldpassword=new JLabel("旧密码:");

	private JPasswordField txtoldpassword=new JPasswordField();

	

	private JLabel lbnewpassword=new JLabel("新密码:");

	private JPasswordField txtnewpassword=new JPasswordField();

	

	private JLabel lbnewpassword2=new JLabel("确认密码:");

	private JPasswordField txtnewpassword2=new JPasswordField();

	

	

	private JButton btnupdate=new JButton("修改");

	private JButton btnreset=new JButton("重置");

	

	User user=LoginFrame.getUser();   //新建User对象

	UpdatePassIFrame()

	{

		this.setSize(new Dimension(320,300));

		this.setLocation(240, 120);

		this.setClosable(true);   //设置窗口可以关闭

		this.setMaximizable(false);    //设置子窗体不允许最大化

		this.setIconifiable(true);   //设置子窗体可以图标化

		this.setTitle("修改密码");

		

		lbusername.setBounds(50, 40, 60, 25);

		txtusername.setBounds(120, 40, 140,25);

		txtusername.setText(user.getUsername());   //将当前登录用户名放入用户名文本框中

		txtusername.setEditable(false);    //设置使调用这个方法的控件不允许被编辑

		

		lboldpassword.setBounds(50, 75, 60, 25);

		txtoldpassword.setBounds(120, 75, 140, 25);

		

		lbnewpassword.setBounds(50, 110, 60, 25);

		txtnewpassword.setBounds(120, 110, 140, 25);

		

		lbnewpassword2.setBounds(50, 145, 60, 25);

		txtnewpassword2.setBounds(120, 145, 140, 25);

		

		btnupdate.setBounds(80, 200, 60, 25);

		btnreset.setBounds(150, 200, 60, 25);

		

		Container cont=this.getContentPane();

		cont.setLayout(null);

		cont.add(lbusername);

		cont.add(txtusername);

		

		cont.add(lboldpassword);

		cont.add(txtoldpassword);

		

		cont.add(lbnewpassword);

		cont.add(txtnewpassword);

		

		cont.add(lbnewpassword2);

		cont.add(txtnewpassword2);

		

		

		cont.add(btnupdate);

		cont.add(btnreset);

		

		btnupdate.addActionListener(new UpdatePasswordAction());   //将修改按钮加入监听事件 

		

		this.setVisible(true);

	}

	private class UpdatePasswordAction implements ActionListener

	{

		

		@Override

		public void actionPerformed(ActionEvent e) {

			String username=user.getUsername();  //用户名是从数据库获取的当前User名字

			String oldpassword=txtoldpassword.getText().trim();  //旧密码为用户输入

			String newpassword=txtnewpassword.getText().trim();

			String newpassword2=txtnewpassword2.getText().trim();

			

			if(null!=oldpassword &&!"".equals(oldpassword))

			{

			  if(oldpassword.equals(user.getPassword())){

				if(null!=newpassword&&!"".equals(newpassword)&&newpassword.equals(newpassword2))

				{

					int flag=Dao.updatePassword(username,newpassword);

					if(flag>0)

					{

						JOptionPane.showMessageDialog(null, "密码修改成功！");

						user.setPassword(newpassword);

					}else{

						JOptionPane.showMessageDialog(null, "密码修改失败！");

					}

				}

				else{

					JOptionPane.showMessageDialog(null, "两次密码不一致或密码为空！");

					txtnewpassword.setText("");

					txtnewpassword2.setText("");

					txtnewpassword.requestFocus();

				}

			  }else{

				  JOptionPane.showMessageDialog(null, "旧密码不正确！");

				  txtoldpassword.setText("");

				  txtoldpassword.requestFocus();

			  }

			}else

			{

				JOptionPane.showMessageDialog(null, "旧密码不能为空！");

				 txtoldpassword.setText("");

				 txtoldpassword.requestFocus();

			}

			

		}

		

	}



}