login.java

java开发的大整数计算器,实现基本的运算,还有sin,cos,tan,cot.

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.*;

import javax.swing.*;


public class Login extends JFrame
{
	private JTextField userName;
	private JPasswordField userPsw;
	private JButton cancel,submit,regist;
	private JPanel namePanel,pswPanel,buttonPanel,mainPanel;
	
	private Regist registGUI;
	
	public Login()
	{
		super("登录");
		
		userName = new JTextField();
		userPsw = new JPasswordField();
		
		registGUI = new Regist();
		
		cancel = new JButton("取消");
		submit = new JButton("确定");
		regist = new JButton("注册");
		
		namePanel = new JPanel(new BorderLayout());
		pswPanel = new JPanel(new BorderLayout());
		buttonPanel = new JPanel(new FlowLayout(FlowLayout.CENTER,5,0));
		mainPanel = new JPanel(new GridLayout(2,1));
		
		namePanel.add(new JLabel("用户名:"),BorderLayout.WEST);
		namePanel.add(userName,BorderLayout.CENTER);
		
		pswPanel.add(new JLabel("    密码:"),BorderLayout.WEST);
		pswPanel.add(userPsw,BorderLayout.CENTER);
		
		mainPanel.add(this.namePanel);
		mainPanel.add(this.pswPanel);
		
		buttonPanel.add(submit);
		buttonPanel.add(cancel);
		buttonPanel.add(regist);
		
		this.add(mainPanel);
		this.add(buttonPanel,BorderLayout.SOUTH);
		this.pack();
		this.setLocationRelativeTo(null);
		this.setDefaultCloseOperation(EXIT_ON_CLOSE);
		
		submit.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				submit();
			}
		});
		
		cancel.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				System.exit(0);
			}
			
		});
		
		regist.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				registGUI.setVisible(true);
			}
			
		});
		
		userName.addKeyListener(new KeyListener()
		{
			public void keyPressed(KeyEvent e)
			{
				System.out.println(e.getKeyCode());
				if(e.getKeyCode() == 10)
					submit();
			}
			public void keyReleased(KeyEvent arg0)
			{}
			public void keyTyped(KeyEvent e)
			{}
		});
		
		userPsw.addKeyListener(new KeyListener()
		{
			public void keyPressed(KeyEvent e)
			{
				System.out.println(e.getKeyCode());
				if(e.getKeyCode() == 10)
					submit();
			}
			public void keyReleased(KeyEvent arg0)
			{}
			public void keyTyped(KeyEvent e)
			{}
		});
	}
	
	private void submit()
	{
		String userNameString = userName.getText(),
		userPswString = new String(userPsw.getPassword());
		
		if(userNameString.length() < 1 || userPswString.length() < 1 )
			
			JOptionPane.showMessageDialog(null,"用户名与密码不能为空");
		
		else
		{
			SqlStatment s = new SqlStatment();
			
			int flag = s.CheckUser(userNameString,userPswString);
			
			if(flag == 0)
			{
				new BigCalculator().setVisible(true);
				hideFrame();
			}
			else
				JOptionPane.showMessageDialog(null,"用户名不存在或密码错误!");
		}
	}
	
	private void hideFrame()
	{
		this.setVisible(false);
	}
}