login.java

综合测评管理系统——完成班级的综合测评工作

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Login{
	//模式对话框
	JDialog LoginDialog;
	int logincount=0;
	//JFrame LoginDialog=new JFrame("LoginSystem");
	static final int WIDTH=320;
	static final int HEIGHT=160;
	
	/*public void actionPerformed(ActionEvent e){
		String cmd=e.getActionCommand();
		if(cmd.equals("login")){
			LoginDialog.dispose();
		}else if(cmd.equals("cancel")){
		  LoginDialog.dispose();
		}
	}*/
	
	public void add(Component c,GridBagConstraints constraints,int x,int y,int w,int h){
	  constraints.gridx=x;
	  constraints.gridy=y;
	  constraints.gridwidth=w;
	  constraints.gridheight=h;
	  LoginDialog.add(c,constraints);
	}
	
	public Login(){
	  //登陆界面的设计
	  LoginDialog=new JDialog();
	  LoginDialog.setTitle("login");
	  LoginDialog.setAlwaysOnTop(false);
	  //LoginDialog.setModal(true);
	  LoginDialog.setModalExclusionType(Dialog.ModalExclusionType.APPLICATION_EXCLUDE);
	  
	  GridBagLayout lay=new GridBagLayout();
	  LoginDialog.setLayout(lay);
	  //LoginDialog.add(frame,BorderLayout.WEST);
	  LoginDialog.setSize(WIDTH,HEIGHT);
	  Toolkit kit=Toolkit.getDefaultToolkit();
	  Dimension screenSize=kit.getScreenSize();
	  int width=screenSize.width;
	  int height=screenSize.height;
	  
	  LoginDialog.setLocation((width-WIDTH)/2,(height-HEIGHT)/2);
	  JButton login=new JButton("login");
	  JButton cancel=new JButton("cancel");
	  
	  JLabel title=new JLabel("班级综合测评管理系统");
	  JLabel username=new JLabel("Username");
	  JLabel password=new JLabel("Password");
	  
	  final JTextField usernameText=new JTextField();
	  final JPasswordField passwordText=new JPasswordField();
	  
	  //布局管理器
	  GridBagConstraints constraints=new GridBagConstraints();
	  constraints.anchor=GridBagConstraints.CENTER;
	  constraints.weightx=3;
	  constraints.weighty=4;
	  constraints.fill=GridBagConstraints.NONE;
	  add(title,constraints,0,0,4,1);
	  //constraints.anchor=GridBagConstraints.EAST;
	  add(username,constraints,0,1,1,1);
	  add(password,constraints,0,2,1,1);
	  constraints.fill=GridBagConstraints.HORIZONTAL;
	  constraints.anchor=GridBagConstraints.CENTER;
	  usernameText.setSize(50,30);
	  add(usernameText,constraints,2,1,3,1);
	  passwordText.setEchoChar('*');
	  add(passwordText,constraints,2,2,3,1);
	  constraints.anchor=GridBagConstraints.CENTER;
	  constraints.fill=GridBagConstraints.NONE;
	  add(login,constraints,0,3,1,1);
	  add(cancel,constraints,2,3,1,1);
	  LoginDialog.setSize(WIDTH,HEIGHT);
	  LoginDialog.setLocation(400,400);
	  LoginDialog.setResizable(false);
	  LoginDialog.setVisible(true);
	  
	  login.addActionListener(new ActionListener(){
	  	public void actionPerformed(ActionEvent Event){
	  		CheckUser cUser=new CheckUser();
	  		String username=usernameText.getText();
	  		//char temp[]=passwordText.getText();
	  		String password=passwordText.getText();
	  		//密码、账号的验证
	  		if(cUser.isValidUser(username,password)==false){
	  			JOptionPane.showMessageDialog(LoginDialog,"错误的用户名或密码","错误",JOptionPane.WARNING_MESSAGE);
	  			logincount++;
	  			if(logincount>=3)
	  			  System.exit(1);
	  		}else{
	  			LoginDialog.dispose();
	  			if(cUser.getUsertype(usernameText.getText())==1){
	  				new AdminFrame(username);
	  			}else{
	  				new GuestFrame(username);
	  			}
	  		}
	  	}
	  });
	  cancel.addActionListener(new ActionListener(){
	  	public void actionPerformed(ActionEvent Event)
	  	{
	  		System.exit(0);
	  	}
	  });
	}
	
	public static void main(String[] args){
		new Login();
	}
}