java用户登录界面
1. 如何用java编写一个简单用户登陆界面
什么都不说了 直接给你代码吧
package com.moliying.ui;
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.List;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Arrays;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
public class Login {
private JFrame frame = new JFrame("登录");
private Container c = frame.getContentPane();
private JTextField username = new JTextField();
private JPasswordField password = new JPasswordField();
private JButton ok = new JButton("确定");
private JButton cancel = new JButton("取消");
public Login() {
frame.setSize(300, 200);
frame.setBounds(450, 300, 300, 200);
c.setLayout(new BorderLayout());
initFrame();
frame.setVisible(true);
}
private void initFrame() {
// 顶部
JPanel titlePanel = new JPanel();
titlePanel.setLayout(new FlowLayout());
titlePanel.add(new JLabel("系统管理员登录"));
c.add(titlePanel, "North");
// 中部表单
JPanel fieldPanel = new JPanel();
fieldPanel.setLayout(null);
JLabel a1 = new JLabel("用户名:");
a1.setBounds(50, 20, 50, 20);
JLabel a2 = new JLabel("密 码:");
a2.setBounds(50, 60, 50, 20);
fieldPanel.add(a1);
fieldPanel.add(a2);
username.setBounds(110, 20, 120, 20);
password.setBounds(110, 60, 120, 20);
fieldPanel.add(username);
fieldPanel.add(password);
c.add(fieldPanel, "Center");
// 底部按钮
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new FlowLayout());
buttonPanel.add(ok);
buttonPanel.add(cancel);
c.add(buttonPanel, "South");
ok.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
System.out.println(username.getText().toString());
}
});
cancel.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
frame.setVisible(false);
}
});
}
public static void main(String[] args) {
// new Login();
String ss = "abbabbbaabbbccba";
System.out.println(ss.split("b").length);
}
}
2. 用java语言写一个用户登陆界面
//这个是我写的，里面有连接数据库的部分。你可以拿去参考一下
importjava.awt.*;
importjavax.swing.*;
importjava.awt.event.*;
importjava.sql.*;
//throwsException
{
JLabellbl1=newJLabel("用户名:");
JLabellbl2=newJLabel("密码:");
JTextFieldtxt=newJTextField(5);
JPasswordFieldpf=newJPasswordField();
JButtonbtn1=newJButton("确定");
JButtonbtn2=newJButton("取消");
publicLoginFrm(){
this.setTitle("登陆");
JPaneljp=(JPanel)this.getContentPane();
jp.setLayout(newGridLayout(3,2,5,5));
jp.add(lbl1);
jp.add(txt);
jp.add(lbl2);
jp.add(pf);
jp.add(btn1);
jp.add(btn2);
btn1.addActionListener(this);
btn2.addActionListener(this);
}
publicvoidactionPerformed(ActionEventae){
if(ae.getSource()==btn1){
try{
Class.forName("com.mysql.jdbc.Driver");//mysql数据库
Connectioncon=DriverManager.getConnection(
"jdbc:mysql://localhost/Car_zl","root","1");//数据库名为Car_zl，密码为1
System.out.println("com:"+con);
Statementcmd=con.createStatement();
Stringsql="select*fromuserwhereUser_ID='"
+txt.getText()+"'andUser_ps='"
+pf.getText()+"'";
ResultSetrs=cmd
.executeQuery(sql);//表名为user，user_ID和User_ps是存放用户名和密码的字段名
if(rs.next()){
JOptionPane.showMessageDialog(null,"登陆成功！");
}else
JOptionPane.showMessageDialog(null,"用户名或密码错误！");
}catch(Exceptionex){
}
if(ae.getSource()==btn2){
System.out.println("1111111111111");
//txt.setText("");
//pf.setText("");
System.exit(0);
}
}
}
publicstaticvoidmain(Stringarg[]){
JFrame.(true);
LoginFrmfrm=newLoginFrm();
frm.setSize(400,200);
frm.setVisible(true);
}
}
3. 登陆界面的java代码怎么写
概述
具体框架使用jframe，文本框组件：JTextField；密码框组件：JPasswordField；标签组件：JLabel；复选框组件：JCheckBox；单选框组件：JRadioButton；按钮组件JButton。
登录界面：
Swing 是一个为Java设计的GUI工具包。
Swing是JAVA基础类的一部分。
Swing包括了图形用户界面（GUI）器件如：文本框，按钮，分隔窗格和表。
Swing提供许多比AWT更好的屏幕显示元素。它们用纯Java写成，所以同Java本身一样可以跨平台运行，这一点不像AWT。它们是JFC的一部分。它们支持可更换的面板和主题（各种操作系统默认的特有主题），然而不是真的使用原生平台提供的设备，而是仅仅在表面上模仿它们。这意味着你可以在任意平台上使用JAVA支持的任意面板。轻量级组件的缺点则是执行速度较慢，优点就是可以在所有平台上采用统一的行为。
概念解析：
JFrame– java的GUI程序的基本思路是以JFrame为基础，它是屏幕上window的对象，能够最大化、最小化、关闭。
JPanel– Java图形用户界面(GUI)工具包swing中的面板容器类，包含在javax.swing 包中，可以进行嵌套，功能是对窗体中具有相同逻辑功能的组件进行组合，是一种轻量级容器，可以加入到JFrame窗体中。。
JLabel– JLabel 对象可以显示文本、图像或同时显示二者。可以通过设置垂直和水平对齐方式，指定标签显示区中标签内容在何处对齐。默认情况下，标签在其显示区内垂直居中对齐。默认情况下，只显示文本的标签是开始边对齐；而只显示图像的标签则水平居中对齐。
JTextField–一个轻量级组件，它允许编辑单行文本。
JPasswordField– 允许我们输入了一行字像输入框，但隐藏星号(*) 或点创建密码(密码)
JButton– JButton 类的实例。用于创建按钮类似实例中的 "Login"。
4. Java编程：登陆界面
publicclassLoginextendsjavax.swing.JFrame{
/**CreatesnewformLogin*/
publicLogin(){
initComponents();
}
/**
*initializetheform.
*WARNING:DoNOTmodifythiscode.Thecontentofthismethodis
*.
*/
//GEN-BEGIN:initComponents
//<editor-folddefaultstate="collapsed"desc="GeneratedCode">
privatevoidinitComponents(){
jPanel1=newjavax.swing.JPanel();
jLabel1=newjavax.swing.JLabel();
jLabel2=newjavax.swing.JLabel();
jTextField1=newjavax.swing.JTextField();
jLabel3=newjavax.swing.JLabel();
jPasswordField1=newjavax.swing.JPasswordField();
jButton1=newjavax.swing.JButton();
jButton2=newjavax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("u7528u6237u767bu5f55");
setBounds(newjava.awt.Rectangle(0,0,180,220));
setResizable(false);
jLabel1.setText("");
jLabel2.setText("u5e10u53f7");
jLabel3.setText("u5bc6u7801");
jButton1.setText("u786eu5b9a");
jButton1.addActionListener(newjava.awt.event.ActionListener(){
publicvoidactionPerformed(java.awt.event.ActionEventevt){
jButton1ActionPerformed(evt);
}
});
jButton2.setText("u53d6u6d88");
jButton2.addActionListener(newjava.awt.event.ActionListener(){
publicvoidactionPerformed(java.awt.event.ActionEventevt){
jButton2ActionPerformed(evt);
}
});
javax.swing.GroupLayoutjPanel1Layout=newjavax.swing.GroupLayout(
jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout
.setHorizontalGroup(jPanel1Layout
.createParallelGroup(
javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(
jPanel1Layout
.createSequentialGroup()
.addGroup(
jPanel1Layout
.createParallelGroup(
javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(
jPanel1Layout
.createSequentialGroup()
.addGap(
31,
31,
31)
.addComponent(
jLabel1))
.addGroup(
jPanel1Layout
.createSequentialGroup()
.addContainerGap()
.addGroup(
jPanel1Layout
.createParallelGroup(
javax.swing.GroupLayout.Alignment.TRAILING,
false)
.addGroup(
javax.swing.GroupLayout.Alignment.LEADING,
jPanel1Layout
.createSequentialGroup()
.addComponent(
jButton1)
.addPreferredGap(
javax.swing.LayoutStyle.ComponentPlacement.RELATED,
javax.swing.GroupLayout.DEFAULT_SIZE,
Short.MAX_VALUE)
.addComponent(
jButton2))
.addGroup(
javax.swing.GroupLayout.Alignment.LEADING,
jPanel1Layout
.createSequentialGroup()
.addComponent(
jLabel3)
.addPreferredGap(
javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(
jPasswordField1))
.addGroup(
javax.swing.GroupLayout.Alignment.LEADING,
jPanel1Layout
.createSequentialGroup()
.addComponent(
jLabel2)
.addPreferredGap(
javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addComponent(
jTextField1,
javax.swing.GroupLayout.PREFERRED_SIZE,
108,
javax.swing.GroupLayout.PREFERRED_SIZE)))))
.addContainerGap(12,Short.MAX_VALUE)));
jPanel1Layout
.setVerticalGroup(jPanel1Layout
.createParallelGroup(
javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(
jPanel1Layout
.createSequentialGroup()
.addContainerGap()
.addComponent(jLabel1)
.addPreferredGap(
javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(
jPanel1Layout
.createParallelGroup(
javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel2)
.addComponent(
jTextField1,
javax.swing.GroupLayout.PREFERRED_SIZE,
javax.swing.GroupLayout.DEFAULT_SIZE,
javax.swing.GroupLayout.PREFERRED_SIZE))
.addPreferredGap(
javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addGroup(
jPanel1Layout
.createParallelGroup(
javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel3)
.addComponent(
jPasswordField1,
javax.swing.GroupLayout.PREFERRED_SIZE,
javax.swing.GroupLayout.DEFAULT_SIZE,
javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(18,18,18)
.addGroup(
jPanel1Layout
.createParallelGroup(
javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jButton1)
.addComponent(jButton2))
.addContainerGap(66,Short.MAX_VALUE)));
javax.swing.GroupLayoutlayout=newjavax.swing.GroupLayout(
getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(layout.createParallelGroup(
javax.swing.GroupLayout.Alignment.LEADING).addComponent(
jPanel1,javax.swing.GroupLayout.DEFAULT_SIZE,
javax.swing.GroupLayout.DEFAULT_SIZE,Short.MAX_VALUE));
layout.setVerticalGroup(layout.createParallelGroup(
javax.swing.GroupLayout.Alignment.LEADING).addComponent(
jPanel1,javax.swing.GroupLayout.DEFAULT_SIZE,
javax.swing.GroupLayout.DEFAULT_SIZE,Short.MAX_VALUE));
pack();
}//</editor-fold>
//GEN-END:initComponents
(java.awt.event.ActionEventevt){
//TODOaddyourhandlingcodehere:
System.exit(0);
}
(java.awt.event.ActionEventevt){
//TODOaddyourhandlingcodehere:
Stringname=jTextField1.getText();
Stringpass=newString(jPasswordField1.getPassword());
System.out.println(name);
System.out.println(pass);
if(name.equals("Java")&&pass.equals("123456")){
jLabel1.setText("登录成功!");
}else{
jLabel1.setText("登录失败!");
}
}
/**
*@
*/
publicstaticvoidmain(Stringargs[]){
java.awt.EventQueue.invokeLater(newRunnable(){
publicvoidrun(){
newLogin().setVisible(true);
}
});
}
//GEN-BEGIN:variables
//Variablesdeclaration-donotmodify
privatejavax.swing.JButtonjButton1;
privatejavax.swing.JButtonjButton2;
privatejavax.swing.JLabeljLabel1;
privatejavax.swing.JLabeljLabel2;
privatejavax.swing.JLabeljLabel3;
privatejavax.swing.JPaneljPanel1;
privatejavax.swing.JPasswordFieldjPasswordField1;
privatejavax.swing.JTextFieldjTextField1;
//Endofvariablesdeclaration//GEN-END:variables
}
5. 如何用java做登录界面
import javax.swing.JFrame;//框架
import javax.swing.JPanel;//面板
import javax.swing.JButton;//按钮
import javax.swing.JLabel;//标签
import javax.swing.JTextField;//文本框
import java.awt.Font;//字体
import java.awt.Color;//颜色
import javax.swing.JPasswordField;//密码框
import java.awt.event.ActionListener;//事件监听
import java.awt.event.ActionEvent;//事件处理
import javax.swing.JOptionPane;//消息窗口public class UserLogIn extends JFrame{
public JPanel pnluser;
public JLabel lbluserLogIn;
public JLabel lbluserName;
public JLabel lbluserPWD;
public JTextField txtName;
public JPasswordField pwdPwd;
public JButton btnSub;
public JButton btnReset;
public UserLogIn(){
pnluser = new JPanel();
lbluserLogIn = new JLabel();
lbluserName = new JLabel();
lbluserPWD = new JLabel();
txtName = new JTextField();
pwdPwd = new JPasswordField();
btnSub = new JButton();
btnReset = new JButton();
userInit();
}
public void userInit(){
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//设置关闭框架的同时结束程序
this.setSize(300,200);//设置框架大小为长300,宽200
this.setResizable(false);//设置框架不可以改变大小
this.setTitle("用户登录");//设置框架标题
this.pnluser.setLayout(null);//设置面板布局管理
this.pnluser.setBackground(Color.cyan);//设置面板背景颜色
this.lbluserLogIn.setText("用户登录");//设置标签标题
this.lbluserLogIn.setFont(new Font("宋体",Font.BOLD | Font.ITALIC,14));//设置标签字体
this.lbluserLogIn.setForeground(Color.RED);//设置标签字体颜色
this.lbluserName.setText("用户名:");
this.lbluserPWD.setText("密 码:");
this.btnSub.setText("登录");
this.btnReset.setText("重置");
this.lbluserLogIn.setBounds(120,15,60,20);//设置标签x坐标120,y坐标15,长60,宽20
this.lbluserName.setBounds(50,55,60,20);
this.lbluserPWD.setBounds(50,85,60,25);
this.txtName.setBounds(110,55,120,20);
this.pwdPwd.setBounds(110,85,120,20);
this.btnSub.setBounds(85,120,60,20);
this.btnSub.addActionListener(new ActionListener()//匿名类实现ActionListener接口
{
public void actionPerformed(ActionEvent e){
btnsub_ActionEvent(e);
}
}
);
this.btnReset.setBounds(155,120,60,20);
this.btnReset.addActionListener(new ActionListener()//匿名类实现ActionListener接口
{
public void actionPerformed(ActionEvent e){
btnreset_ActionEvent(e);
}
}
);
this.pnluser.add(lbluserLogIn);//加载标签到面板
this.pnluser.add(lbluserName);
this.pnluser.add(lbluserPWD);
this.pnluser.add(txtName);
this.pnluser.add(pwdPwd);
this.pnluser.add(btnSub);
this.pnluser.add(btnReset);
this.add(pnluser);//加载面板到框架
this.setVisible(true);//设置框架可显
}
public void btnsub_ActionEvent(ActionEvent e){
String name = txtName.getText();
String pwd = String.valueOf(pwdPwd.getPassword());
if(name.equals("")){
JOptionPane.showMessageDialog(null,"账号不能为空","错误",JOptionPane.ERROR_MESSAGE);
return;
}else if (pwd.equals("")){
JOptionPane.showMessageDialog(null,"密码不能为空","错误",JOptionPane.ERROR_MESSAGE);
return;
}else if(true){
this.dispose();
}else{
JOptionPane.showMessageDialog(null,"账号或密码错误","错误",JOptionPane.ERROR_MESSAGE);
return;
}
}
public void btnreset_ActionEvent(ActionEvent e){
txtName.setText("");
pwdPwd.setText("");
}
public static void main(String[] args){
new UserLogIn();
}
}
6. JAVA用户登录界面的编程思想和方法是什么
登录界面一般涉及登录 退出
一般登录使用用户名和密码，使用数据库校验即可（密码可能加密）
校验通过即成功
另外，为了鉴权和避免重复校验，一般登录会返回一个时效并包含登录信息的token，根据token可直接登录
此时，退出操作，就是删除此token；
jwt可以参考下
7. Java制作一个用户登录的窗口
Java用户登陆这块，主要还是类：
1，边界布局：BorderLayout。他主要分为五个布局，是JFrame(顶层容器)，JDialog(创建对话框窗口的类)的默认布局方式。其最多容量为5个组件，超出5个得用其他的。设置方式为：BorderLayout.NORTH;BorderLayout.SOUTH;BorderLayout.CENTER;Borderlayout.CENTER;BorderLayout.LEFT;BorderLayout.RIGHT。
2，流式布局：FlowLayout。布局方式为从左到右，从上到下。是JPanel(轻量级容器)的默认面板布局。
3，网格布局：GridLayout。布局方式为行和列组成的网络。布局方法：setLayout(new
GridLayout(3,2,3,3));其中强两位数字表示三行两列，后两位表示行与行的间距为3，列与列的间距为3.
接着，就接触到JPanel面板。JPanel是非顶层容器，所以，一个界面只能由一个JFrame，但是可以有多个JPanel组件。其默认布局方式为流式布局。在JPanel这块，学到了用户登录界面的设计。从而接触到另外三个组件：文本框组件：JTextField;密码框组件：JPasswordField;标签组件：JLabel;复选框组件：JCheckBox;单选框组件：JRadioButton;按钮组件JButton。
8. 求JAVA实现用户登录界面代码
求麦克实现登录用户密码，电费就点击x加y就可以了。
9. java用户登录界面的设计
import javax.swing.*;
import java.awt.*;
public class Frame extends JFrame {
public static void main(String[] args) {
new Frame();
}
public Frame() throws HeadlessException {
Container contentPanel = this.getContentPane();
JPanel headerPanel = new JPanel();
headerPanel.setLayout(new FlowLayout());
headerPanel.add(new JLabel("欢迎进入学生成绩管理系统"));
JPanel centerPanel = new JPanel();
centerPanel.setLayout(new GridLayout(2, 2));
centerPanel.add(new JLabel("用户名", JLabel.CENTER));
centerPanel.add(new JTextField());
centerPanel.add(new JLabel("密码", JLabel.CENTER));
centerPanel.add(new JTextField());
JPanel footerPanel = new JPanel();
footerPanel.setLayout(new FlowLayout());
footerPanel.add(new JButton("登录"));
footerPanel.add(new JButton("取消"));
contentPanel.add(headerPanel, BorderLayout.NORTH);
contentPanel.add(centerPanel, BorderLayout.CENTER);
contentPanel.add(footerPanel, BorderLayout.SOUTH);
this.setTitle("Login");
this.setBounds(0, 0, 300, 200);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
}
}
10. 用java程序编写一个简单的登录界面怎么写
程序如下:
mport java.awt.HeadlessException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
@SuppressWarnings("serial")
public class MainFrame extends JFrame {
JLabel lbl1 = new JLabel("用户名:");
JLabel lbl2 = new JLabel("密 码:");
JTextField txt = new JTextField("admin",20);
JPasswordField pwd = new JPasswordField(20);
JButton btn = new JButton("登录");
JPanel pnl = new JPanel();
private int error = 0;
public MainFrame(String title) throws HeadlessException {
super(title);
init();
}
private void init() {
this.setResizable(false);
pwd.setEchoChar('*');
pnl.add(lbl1);
pnl.add(txt);
btn.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if ("admin".equal花憨羔窖薏忌割媳公颅s(new String(pwd.getPassword()))){
pnl.removeAll();
JLabel lbl3 = new JLabel();
ImageIcon icon = new ImageIcon(this.getClass().getResource("pic.jpg"));
lbl3.setIcon(icon);
pnl.add(lbl3);
}
else{
if(error < 3){
JOptionPane.showMessageDialog(null,"密码输入错误，请再试一次");
error++;
}
else{
JOptionPane.showMessageDialog(null,"对不起，您不是合法用户");
txt.setEnabled(false);
pwd.setEnabled(false);
btn.setEnabled(false);
}
}
}
});
}
public static void main(String[] args) {
MainFrame frm = new MainFrame("测试");
frm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frm.setBounds(100, 100, 300, 120);
frm.setVisible(true);
}
}