Java心得27

今天跟大家分型一个案例：

package test;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.JFrame;

import javax.swing.JOptionPane;

import com.lovo.netCRM.component.LovoButton;

import com.lovo.netCRM.component.LovoTxt;

public class LoginFrame extends JFrame{

private LovoTxt nameTxt = new LovoTxt("用户名",50,50,this);

private LovoTxt pwdTxt = new LovoTxt("密码",50,200,this);

private LogObj lo = new LogObj();

public LoginFrame(){

this.setLayout(null);

LovoButton loginButton = new LovoButton("登陆",300,300,this);

loginButton.addActionListener(new ActionListener() {

@Override

public void actionPerformed(ActionEvent arg0) {

if("123".equals(nameTxt.getText()) && "456".equals(pwdTxt.getText())){

JOptionPane.showMessageDialog(null, "登陆成功");

lo.writeLog("张三在15:32:30登陆系统");

}else{

JOptionPane.showMessageDialog(null, "登陆失败");

lo.writeLog("非法用户张三在15:32:30 企图登陆系统");

}

}

});

this.setSize(500,400);

this.setVisible(true);

this.setDefaultCloseOperation(3);

this.setLocationRelativeTo(null);

}

public static void main(String[] args) {

LoginFrame lf = new LoginFrame();

}

}

package test;

import java.io.BufferedWriter;

import java.io.File;

import java.io.FileWriter;

import java.io.IOException;

import java.io.Writer;

import java.text.SimpleDateFormat;

import java.util.Date;

public class LogObj {

public void writeLog(String info){

File f = new File("log");

if(f.exists()==false){

f.mkdir();

}

Writer w = null;

BufferedWriter bw = null;

try {

w = new FileWriter("log.txt");

bw= new BufferedWriter(w);

bw.write(info);

bw.newLine();

SimpleDateFormat s = new SimpleDateFormat("yyyy-MM-dd");

String str = s.format(new Date());

bw.write(str);

} catch (Exception e) {

e.printStackTrace();

}finally{

try {

bw.close();

w.close();

} catch (IOException e) {

e.printStackTrace();

}

}

}

}