import java.awt.*\x0d\x0aimport javax.swing.*\x0d\x0aimport java.awt.event.*\x0d\x0aimport java.sql.*\x0d\x0a\x0d\x0aclass LoginFrm extends JFrame implements ActionListener \x0d\x0a{ \x0d\x0aJLabel lbl1=new JLabel("
用户名")\x0d\x0aJLabel lbl2=new JLabel("
密码")\x0d\x0aJTextField txt=new JTextField(15)\x0d\x0aJPasswordField pf=new JPasswordField()\x0d\x0aJButton btn1=new JButton("确定")\x0d\x0aJButton btn2=new JButton("取消")\x0d\x0a\x0d\x0apublic LoginFrm() \x0d\x0a{ \x0d\x0athis.setTitle("登陆")\x0d\x0aJPanel jp=(JPanel)this.getContentPane()\x0d\x0ajp.setLayout(new GridLayout(3,2,10,10))\x0d\x0ajp.add(lbl1)jp.add(txt)\x0d\x0ajp.add(lbl2)jp.add(pf)\x0d\x0ajp.add(btn1)jp.add(btn2)\x0d\x0abtn1.addActionListener(this)\x0d\x0abtn2.addActionListener(this)\x0d\x0a} \x0d\x0a\x0d\x0apublic void actionPerformed(ActionEvent ae) \x0d\x0a{ \x0d\x0aif(ae.getSource()==btn1) \x0d\x0a{ \x0d\x0atry \x0d\x0a{ \x0d\x0aClass.forName("sun.jdbc.odbc.JdbcOdbcDriver")； \x0d\x0aConnection con=DriverManager.getConnection("jdbc:odbc:MyDB","","")\x0d\x0aStatement cmd=con.createStatement()\x0d\x0aResultSet rs=cmd.executeQuery("select * from loginAndpassword where login='"+txt.getText()+"' and password='"+pf.getText()+"'")\x0d\x0aif(rs.next()) \x0d\x0a{ \x0d\x0aJOptionPane.showMessageDialog(null,"登陆成功！")\x0d\x0a} \x0d\x0aelse \x0d\x0aJOptionPane.showMessageDialog(null,"用户名或密码错误！")\x0d\x0a} catch(Exception ex){} \x0d\x0a\x0d\x0aif(ae.getSource()==btn2) \x0d\x0a{ \x0d\x0atxt.setText("")\x0d\x0apf.setText("")\x0d\x0a} \x0d\x0a} \x0d\x0a} \x0d\x0a\x0d\x0apublic static void main(String arg[]) \x0d\x0a{ \x0d\x0aJFrame.setDefaultLookAndFeelDecorated(true)\x0d\x0aLoginFrm frm=new LoginFrm()\x0d\x0afrm.setSize(400,200)\x0d\x0afrm.setVisible(true)\x0d\x0a} \x0d\x0a}
第一个java文件LogoingDemo.java
import java.util.Scanner
public class LogoingDemo {
public static void main(String[] args) {
System.out.println("请输入用户名")
Scanner sc = new Scanner(System.in)
String name = sc.nextLine()
System.out.println("请输入密码")
String psw = sc.nextLine()
sc.close()
CheckDemo cd = new CheckDemo(name,psw)//用户名和密码传入验证类
boolean bo = cd.check()//调用方法进行验证
if(bo){
System.out.println("登录成功")
}else{
System.out.println("登录失败:提示 用户名 admin 密码123")
}
}
}
第二个java文件CheckDemo.java
public class CheckDemo {
public String name
public String psw
public CheckDemo(String name,String psw){//构造器
this.name = name
this.psw = psw
}
public boolean check() {
// 用户名 密码不能为空. 用户名=admin 密码 = 123
if (name != null && psw != null && name.equals("admin") && psw.equals("123")) {
return true
}
return false
}
}
效果
请输入用户名
admin
请输入密码
123
登录成功
------------------------------------
请输入用户名
add
请输入密码
123
登录失败:提示 用户名 admin 密码123
