denglu.java

java写的xuesheng信息管理系统！欢迎下载使用

//两个判断......


import java.awt.*;
import java.awt.event.*;
import java.io.IOException;
import java.sql.*;

import javax.swing.*;

public class Denglu extends JFrame
{ int  count=0;
	JPanel p1=new JPanel();
	JPanel p2=new JPanel();
	JPanel p3=new JPanel();
	JPanel p4=new JPanel();
	
	JLabel l1=new JLabel("输入用户名：");
	JLabel l2=new JLabel("请输入密码：");
	JLabel l3=new JLabel("请选择身份：");
	
	static JTextField f1=new JTextField(16);
	//JTextField f2=new JTextField(16);
	
	JPasswordField  f2=new JPasswordField("",16);
	
	Choice shenfen=new Choice();
	
	
	JButton bu1=new JButton("确定");
	
     public Denglu()
	{
		super("请登录");
		
		this.setBounds(400,300,300,200);
		
		
		this.setLayout(new GridLayout(4,1));
		this.add(p1);
		this.add(p2);
		this.add(p3);
		this.add(p4);
		
		shenfen.add("请选择");
		shenfen.add("学生");
		shenfen.add("管理员");
		
		p1.add(l1);
		p1.add(f1);
		p2.add(l2);
		p2.add(f2);
		p3.add(l3);
		p3.add(shenfen);
		p4.add(bu1);
		
		
		shenfen.addItemListener(
				new ItemListener()
				{

					public void itemStateChanged(ItemEvent e) 
					{
						Choice temp=(Choice)e.getItemSelectable();
						final String url="jdbc:odbc:stuinf";
						final String sql="select * from Admin";
						final String sqlstudent="select * from Student";
						try
						{
							Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

						}
						catch(java.lang.ClassNotFoundException e1)
						{
							
						}
						if(f1.getText().length()<=0||f2.getText().length()<=0)
						{
							bu1.addActionListener(
									new ActionListener()
									{

										public void actionPerformed(ActionEvent e)
										{
							Error er=new Error();
							er.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
							er.setVisible(true);
							//count++; if(count==18) er.setVisible(true);
							Denglu.this.dispose();
										}
									}
							);
									
						
							System.out.print("输入的姓名或密码为空错误!");
						}
						else
						{
							if(temp.getSelectedItem()=="学生")
							{
								bu1.addActionListener(
										new ActionListener()
										{

											public void actionPerformed(ActionEvent e)
											{
												try
												{
													Connection con=DriverManager.getConnection(url,"","");
													Statement stmt=con.createStatement();
	
													ResultSet rs=stmt.executeQuery(sqlstudent);
													if(rs.next())
													{
														String s1=rs.getString("Sno");
														String s2=rs.getString("Spwd");
	
														System.out.print(s2+","+s1);//判断输出结果
														System.out.print("进行下步操作！");
													if(f1.getText().equals(s1.trim()))
														{
														   
															if(f2.getText().equals(s2.trim()))
															{
																Gerenjiemian xx=new Gerenjiemian();
																xx.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
																xx.setVisible(true);
																
																Denglu.this.dispose();
															}
															else
															{
																Error er=new Error();
																er.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
																er.setVisible(true);
																//count++; if(count==18) er.setVisible(true);
																Denglu.this.dispose();
																//.trim()
																
															}
															
														}
														
														else
														{
															Error er=new Error();
															er.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
															er.setVisible(true);
															//count++; if(count==18) er.setVisible(true);
															Denglu.this.dispose();
														}
													  
													}
													stmt.close();
													con.close();
												
												}
												catch(SQLException ex)
												{
													System.out.print(ex.getMessage());
												}
												
											}
											
										}
										);
							}
							else
							{
								bu1.addActionListener(
										new ActionListener()
										{

											public void actionPerformed(ActionEvent e)											{
												try
												{
													Connection con=DriverManager.getConnection(url,"","");
													Statement stmt=con.createStatement();
	
													ResultSet rs=stmt.executeQuery(sql);
													while(rs.next())
													{
														String s1=rs.getString("Aname");
														String s2=rs.getString("Apwd");
														
														
													System.out.print(s1+","+s2);//判断输出结果
														
														System.out.print("进行下步操作！");
													if(f1.getText().equals(s1))
														{
														   
															if(f2.getText().equals(s2))
															{
																Xinxicaozuo xxcz=new Xinxicaozuo();
																xxcz.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
																xxcz.setVisible(true);
																Denglu.this.dispose();
															}
															else
															{
																Error er=new Error();
																er.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
																er.setVisible(true);
																Denglu.this.dispose();
															}
														}
														else
														{
															Error er=new Error();
															er.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
															er.setVisible(true);
															Denglu.this.dispose();
														}
													}
													stmt.close();
													con.close();
												
												}
												catch(SQLException ex)
												{
													System.out.print(ex.getMessage());
												}
												
											}
											
										}
										);
								
							}
	
						}
						
					}
					
				}
		);
	
	
	}

    public static JTextField getF1() {
		return f1;
	}

	public static void setF1(JTextField f1) {
		Denglu.f1 = f1;
	}

}