java登陸
1. 用java編寫一個登陸系統。
第一個java文件LogoingDemo.java
importjava.util.Scanner;
publicclassLogoingDemo{
publicstaticvoidmain(String[]args){
System.out.println("請輸入用戶名");
Scannersc=newScanner(System.in);
Stringname=sc.nextLine();
System.out.println("請輸入密碼");
Stringpsw=sc.nextLine();
sc.close();
CheckDemocd=newCheckDemo(name,psw);//用戶名和密碼傳入驗證類
booleanbo=cd.check();//調用方法進行驗證
if(bo){
System.out.println("登錄成功");
}else{
System.out.println("登錄失敗:提示用戶名admin密碼123");
}
}
}
第二個java文件CheckDemo.java
publicclassCheckDemo{
publicStringname;
publicStringpsw;
publicCheckDemo(Stringname,Stringpsw){//構造器
this.name=name;
this.psw=psw;
}
publicbooleancheck(){
//用戶名密碼不能為空.用戶名=admin密碼=123
if(name!=null&&psw!=null&&name.equals("admin")&&psw.equals("123")){
returntrue;
}
returnfalse;
}
}效果
請輸入用戶名
admin
請輸入密碼
123
登錄成功
------------------------------------
請輸入用戶名
add
請輸入密碼
123
登錄失敗:提示用戶名admin密碼123
2. 如何用java做登錄界面
import javax.swing.JFrame;//框架
import javax.swing.JPanel;//面板
import javax.swing.JButton;//按鈕
import javax.swing.JLabel;//標簽
import javax.swing.JTextField;//文本框
import java.awt.Font;//字體
import java.awt.Color;//顏色
import javax.swing.JPasswordField;//密碼框
import java.awt.event.ActionListener;//事件監聽
import java.awt.event.ActionEvent;//事件處理
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);//設置關閉框架的同時結束程序
this.setSize(300,200);//設置框架大小為長300,寬200
this.setResizable(false);//設置框架不可以改變大小
this.setTitle("用戶登錄");//設置框架標題
this.pnluser.setLayout(null);//設置面板布局管理
this.pnluser.setBackground(Color.cyan);//設置面板背景顏色
this.lbluserLogIn.setText("用戶登錄");//設置標簽標題
this.lbluserLogIn.setFont(new Font("宋體",Font.BOLD | Font.ITALIC,14));//設置標簽字體
this.lbluserLogIn.setForeground(Color.RED);//設置標簽字體顏色
this.lbluserName.setText("用戶名:");
this.lbluserPWD.setText("密 碼:");
this.btnSub.setText("登錄");
this.btnReset.setText("重置");
this.lbluserLogIn.setBounds(120,15,60,20);//設置標簽x坐標120,y坐標15,長60,寬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()//匿名類實現ActionListener介面
{
public void actionPerformed(ActionEvent e){
btnsub_ActionEvent(e);
}
}
);
this.btnReset.setBounds(155,120,60,20);
this.btnReset.addActionListener(new ActionListener()//匿名類實現ActionListener介面
{
public void actionPerformed(ActionEvent e){
btnreset_ActionEvent(e);
}
}
);
this.pnluser.add(lbluserLogIn);//載入標簽到面板
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);//載入面板到框架
this.setVisible(true);//設置框架可顯
}
public void btnsub_ActionEvent(ActionEvent e){
String name = txtName.getText();
String pwd = String.valueOf(pwdPwd.getPassword());
if(name.equals("")){
JOptionPane.showMessageDialog(null,"賬號不能為空","錯誤",JOptionPane.ERROR_MESSAGE);
return;
}else if (pwd.equals("")){
JOptionPane.showMessageDialog(null,"密碼不能為空","錯誤",JOptionPane.ERROR_MESSAGE);
return;
}else if(true){
this.dispose();
}else{
JOptionPane.showMessageDialog(null,"賬號或密碼錯誤","錯誤",JOptionPane.ERROR_MESSAGE);
return;
}
}
public void btnreset_ActionEvent(ActionEvent e){
txtName.setText("");
pwdPwd.setText("");
}
public static void main(String[] args){
new UserLogIn();
}
}
3. java怎樣實現登錄驗證
1.打開編程工具：
打開java編程的界面，採用的是eclipse軟體；
4. java編寫用戶登錄
代碼發給你，如果什麼都不懂的話，估計你也難以運行成功，而且圖片也沒有，要自己會改就能運行了。這些代碼希望能幫到你！
資料庫文件：
create database hotel_Flyer
go
use hotel_Flyer
create table userInfo(
id int primary key identity(1,1),
userName varchar(20),
password varchar(10),
realName nvarchar(20),
sex nvarchar(2),
age int,
favorite nvarchar(100),
telNum varchar(12),
email varchar(50),
address nvarchar(200)
)
go
insert into userInfo(userName,password) values('李連傑','123')
insert into userInfo(userName,password) values('成龍','123')
insert into userInfo(userName,password) values('甄子丹','123')
insert into userInfo(userName,password) values('趙文卓','123')
insert into userInfo(userName,password) values('吳京','123')
insert into userInfo(userName,password) values('周星馳','123')
insert into userInfo(userName,password) values('劉德華','123')
載入驅動類：
public class ConTosql {
Connection con=null;
public Connection getConnection() throws Exception{
Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
con= DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;databaseName=hotel_Flyer", "sa", "sa");
return con;
}
}
連接資料庫類：
public class DengluUC {
Connection con=null;
PreparedStatement stm=null;
ResultSet rs=null;
public boolean checkUser(String user,String pwd){
boolean tof=false;
try {
ConToSQL cts=new ConToSQL();
con=cts.getConnection();
stm=con.prepareStatement("select password from userInfo where userName=?");
stm.setString(1, user);
rs=stm.executeQuery();
if(rs.next()){
if(rs.getString(1).equals(pwd)){
tof= true;
}
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
} /*finally{
try {
rs.close();
stm.close();
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
return tof;
}*/
return tof;
}
}
登錄類代碼：
package com.hbsoft.hotel_Flyer.login;
import com.hbsoft.hotel_Flyer.usermanagerForm.*;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridBagLayout;
import java.awt.Rectangle;
import javax.swing.BorderFactory;
import java.awt.Color;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.swing.JComboBox;
import javax.swing.JOptionPane;
import javax.swing.JPasswordField;
import javax.swing.JButton;
import javax.swing.ImageIcon;
import javax.swing.JTextField;
import javax.swing.text.html.Option;
import com.hbsoft.hotel_Flyer.proc.Process;
import java.awt.Point;
import java.sql.*;
import com.hbsoft.hotel_Flyer.database.*;
public class Denglu {
private JFrame jFrame = null; // @jve:decl-index=0:visual-constraint="61,26"
private JPanel jContentPane = null;
private JPanel jPanel = null;
private JComboBox jComboBox = null;
private JLabel jL4 = null;
private JLabel jLabel1 = null;
private JPasswordField jPasswordField = null;
private JButton jB1 = null;
private JButton jB2 = null;
private JComboBox jComboBox1 = null;
private JLabel jLabel = null;
private JLabel jLabel2 = null;
private Connection con=null; // @jve:decl-index=0:
private Statement sts=null;
private ResultSet rs=null;
private DatabaseMetaData dmd=null;
private int rowCount=0;
/**
* This method initializes jFrame
*
* @return javax.swing.JFrame
*/
public JFrame getJFrame() {
if (jFrame == null) {
jFrame = new JFrame("系統登陸");
jFrame.setSize(new Dimension(854, 539));
jFrame.setLocation(new Point(100, 100));
jFrame.setContentPane(getJContentPane());
jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jFrame.setResizable(false);
}
return jFrame;
}
/**
* This method initializes jContentPane
*
* @return javax.swing.JPanel
*/
private JPanel getJContentPane() {
if (jContentPane == null) {
jLabel2 = new JLabel();
jLabel2.setBounds(new Rectangle(3, 4, 845, 503));
jLabel2.setIcon(new ImageIcon("E:/java\uff088\uff09\u73ed\u5468\u67ab/\u7b2c\u5341\u7ec4\u5de5\u4f5c\u7ad9/hotel_Flyer/\u767b\u5f55\u80cc\u666f.jpg"));
jLabel2.setText("");
jLabel = new JLabel();
jLabel.setText("");
jLabel.setIcon(new ImageIcon(getClass().getResource("/com/hbsoft/hotel_Flyer/img/\u767b\u5f55\u80cc\u666f.jpg")));
jLabel.setBounds(new Rectangle(-1, 1, 851, 509));
jLabel1 = new JLabel();
jLabel1.setBounds(new Rectangle(438, 141, 363, 231));
jLabel1.setText("");
jL4 = new JLabel();
jL4.setBounds(new Rectangle(484, 341, 289, 28));
jL4.setHorizontalAlignment(SwingConstants.CENTER);
Timer t =new Timer(1000,new ActionListener(){
public void actionPerformed(ActionEvent e) {
Date d=new Date();
SimpleDateFormat df = new SimpleDateFormat("yy-MM-dd hh:mm:ss");
jL4.setText(df.format(d));
}
});
t.start();
jContentPane = new JPanel();
jContentPane.setLayout(null);
jContentPane.setBorder(BorderFactory.createLineBorder(Color.cyan, 2));
jContentPane.setFont(new Font("\u96b6\u4e66", Font.PLAIN, 14));
jContentPane.add(getJPanel(), null);
jContentPane.add(jL4, null);
jContentPane.add(jLabel1, null);
jContentPane.add(getJPasswordField(), null);
jContentPane.add(getJB1(), null);
jContentPane.add(getJB2(), null);
jContentPane.add(getJComboBox1(), null);
jContentPane.add(jLabel, null);
jContentPane.add(jLabel2, null);
jContentPane.add(jLabel, null);
}
return jContentPane;
}
/**
* This method initializes jPanel
*
* @return javax.swing.JPanel
*/
private JPanel getJPanel() {
if (jPanel == null) {
jPanel = new JPanel();
jPanel.setLayout(new GridBagLayout());
jPanel.setBounds(new Rectangle(0, 0, 415, 0));
}
return jPanel;
}
/**
* This method initializes jB1
*
* @return javax.swing.JButton
*/
void ThisDispose(){
this.getJFrame().dispose();
}
/**
* This method initializes jPasswordField
*
* @return javax.swing.JPasswordField
*/
private JPasswordField getJPasswordField() {
if (jPasswordField == null) {
jPasswordField = new JPasswordField();
jPasswordField.setBounds(new Rectangle(570, 263, 201, 29));
}
return jPasswordField;
}
/**
* This method initializes jB1
*
* @return javax.swing.JButton
*/
/*void ThisdDispose(){
this.getJFrame().dispose();
}*/
private JButton getJB1() {
if (jB1 == null) {
jB1 = new JButton();
jB1.setBounds(new Rectangle(489, 313, 103, 35));
jB1.setText("登陸");
jB1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent e) {
if(new DengluUC().checkUser(jComboBox1.getSelectedItem().toString(), new String(jPasswordField.getPassword()))){
//message.setText("登錄成功");
//message.setForeground(new Color(255,0,0));
new Process((String)jComboBox1.getSelectedItem()).setVisible(true);
ThisDispose();
}else{
if(new String(jPasswordField.getPassword()).length()==0){
JOptionPane.showMessageDialog(null, "密碼不能為空");
}else{
JOptionPane.showMessageDialog(null, "密碼不正確，請重新輸入");
}
}
}
});
}
return jB1;
}
/**
* This method initializes jB2
*
* @return javax.swing.JButton
*/
private JButton getJB2() {
if (jB2 == null) {
jB2 = new JButton();
jB2.setBounds(new Rectangle(642, 312, 103, 35));
jB2.setText("退出");
jB2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent e) {
System.exit(0);
}
});
}
return jB2;
}
/**
* This method initializes jComboBox1
*
* @return javax.swing.JComboBox
*/
public void getResultSet(){
try{
con=new ConToSQL().getConnection();
sts=con.createStatement();
rs=sts.executeQuery("select * from userInfo");
}catch(Exception e){
e.printStackTrace();
}
}
public int getRowCount(){
try {
rs.last();
if (rs.isLast()) {
rowCount = rs.getRow();
}
} catch (Exception e) {
e.printStackTrace();
}
return rowCount;
}
public void closeData(){
try{
rs.close();
sts.close();
con.close();
}catch(SQLException e){
e.printStackTrace();
}
}
private JComboBox getJComboBox1() {
getResultSet();
String [] arr=new String[7];
int i=0;
try {
while (rs.next()) {
if(i<arr.length){
arr[i] = rs.getString(2);
i++;}
}
} catch (Exception e) {
e.printStackTrace();
}
if (jComboBox1 == null) {
jComboBox1 = new JComboBox(arr);
closeData();
jComboBox1.setBounds(new Rectangle(569, 218, 201, 29));
}
return jComboBox1;
}
public static void main(String [] args) throws Exception{
// javax.swing.UIManager.setLookAndFeel("com.jtattoo.plaf.mcwin.McWinLookAndFeel");
javax.swing.UIManager.setLookAndFeel("com.jtattoo.plaf.acryl.AcrylLookAndFeel");
new Denglu().getJFrame().setVisible(true);
}
}
5. Java中登陸時如何實現的
如果時java web開發的話，那就是跟資料庫掛鉤了。用戶輸入用戶名和密碼，然後後台程序和資料庫保存的用戶名和密碼進行比較，如果成功，就進入允許的界面，如果不成功，重新回到登錄界面，或者返回網站首頁。
希望能幫到你！！！
6. java語言實現用戶注冊和登錄
//這個是我寫的，裡面有連接資料庫的部分。你可以拿去參考一下
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.sql.*;
class LoginFrm extends JFrame implements ActionListener// throws Exception
{
JLabel lbl1 = new JLabel("用戶名:");
JLabel lbl2 = new JLabel("密碼:");
JTextField txt = new JTextField(5);
JPasswordField pf = new JPasswordField();
JButton btn1 = new JButton("確定");
JButton btn2 = new JButton("取消");
public LoginFrm() {
this.setTitle("登陸");
JPanel jp = (JPanel) this.getContentPane();
jp.setLayout(new GridLayout(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);
}
public void actionPerformed(ActionEvent ae) {
if (ae.getSource() == btn1) {
try {
Class.forName("com.mysql.jdbc.Driver");// mysql資料庫
Connection con = DriverManager.getConnection(
"jdbc:mysql://localhost/Car_zl", "root", "1");// 資料庫名為Car_zl，密碼為1
System.out.println("com : "+ con);
Statement cmd = con.createStatement();
String sql = "select * from user where User_ID='"
+ txt.getText() + "' and User_ps='"
+ pf.getText() + "'" ;
ResultSet rs = cmd
.executeQuery(sql);// 表名為user，user_ID和User_ps是存放用戶名和密碼的欄位名
if (rs.next()) {
JOptionPane.showMessageDialog(null, "登陸成功！");
} else
JOptionPane.showMessageDialog(null, "用戶名或密碼錯誤！");
} catch (Exception ex) {
}
if (ae.getSource() == btn2) {
System.out.println("1111111111111");
//txt.setText("");
//pf.setText("");
System.exit(0);
}
}
}
public static void main(String arg[]) {
JFrame.(true);
LoginFrm frm = new LoginFrm();
frm.setSize(400, 200);
frm.setVisible(true);
}
}
7. java實現簡單登錄界面
自己寫的比較規范的代碼，都有注釋:
import javax.swing.JFrame;//框架
import javax.swing.JPanel;//面板
import javax.swing.JButton;//按鈕
import javax.swing.JLabel;//標簽
import javax.swing.JTextField;//文本框
import java.awt.Font;//字體
import java.awt.Color;//顏色
import javax.swing.JPasswordField;//密碼框
import java.awt.event.ActionListener;//事件監聽
import java.awt.event.ActionEvent;//事件處理
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);//設置關閉框架的同時結束程序
this.setSize(300,200);//設置框架大小為長300,寬200
this.setResizable(false);//設置框架不可以改變大小
this.setTitle("用戶登錄");//設置框架標題
this.pnluser.setLayout(null);//設置面板布局管理
this.pnluser.setBackground(Color.cyan);//設置面板背景顏色
this.lbluserLogIn.setText("用戶登錄");//設置標簽標題
this.lbluserLogIn.setFont(new Font("宋體",Font.BOLD | Font.ITALIC,14));//設置標簽字體
this.lbluserLogIn.setForeground(Color.RED);//設置標簽字體顏色
this.lbluserName.setText("用戶名:");
this.lbluserPWD.setText("密 碼:");
this.btnSub.setText("登錄");
this.btnReset.setText("重置");
this.lbluserLogIn.setBounds(120,15,60,20);//設置標簽x坐標120,y坐標15,長60,寬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()//匿名類實現ActionListener介面
{
public void actionPerformed(ActionEvent e){
btnsub_ActionEvent(e);
}
}
);
this.btnReset.setBounds(155,120,60,20);
this.btnReset.addActionListener(new ActionListener()//匿名類實現ActionListener介面
{
public void actionPerformed(ActionEvent e){
btnreset_ActionEvent(e);
}
}
);
this.pnluser.add(lbluserLogIn);//載入標簽到面板
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);//載入面板到框架
this.setVisible(true);//設置框架可顯
}
public void btnsub_ActionEvent(ActionEvent e){
String name = txtName.getText();
String pwd = String.valueOf(pwdPwd.getPassword());
if(name.equals("")){
JOptionPane.showMessageDialog(null,"賬號不能為空","錯誤",JOptionPane.ERROR_MESSAGE);
return;
}else if (pwd.equals("")){
JOptionPane.showMessageDialog(null,"密碼不能為空","錯誤",JOptionPane.ERROR_MESSAGE);
return;
}else if(true){
this.dispose();
}else{
JOptionPane.showMessageDialog(null,"賬號或密碼錯誤","錯誤",JOptionPane.ERROR_MESSAGE);
return;
}
}
public void btnreset_ActionEvent(ActionEvent e){
txtName.setText("");
pwdPwd.setText("");
}
public static void main(String[] args){
new UserLogIn();
}
}
8. 用java寫一個登陸界面代碼。
概述
具體框架使用jframe，文本框組件：JTextField；密碼框組件：JPasswordField；標簽組件：JLabel；復選框組件：JCheckBox；單選框組件：JRadioButton；按鈕組件JButton。
登錄界面：
Swing 是一個為Java設計的GUI工具包。
Swing是JAVA基礎類的一部分。
Swing包括了圖形用戶界面（GUI）器件如：文本框，按鈕，分隔窗格和表。
Swing提供許多比AWT更好的屏幕顯示元素。它們用純Java寫成，所以同Java本身一樣可以跨平台運行，這一點不像AWT。它們是JFC的一部分。它們支持可更換的面板和主題（各種操作系統默認的特有主題），然而不是真的使用原生平台提供的設備，而是僅僅在表面上模仿它們。這意味著你可以在任意平台上使用JAVA支持的任意麵板。輕量級組件的缺點則是執行速度較慢，優點就是可以在所有平台上採用統一的行為。
概念解析：
JFrame– java的GUI程序的基本思路是以JFrame為基礎，它是屏幕上window的對象，能夠最大化、最小化、關閉。
JPanel– Java圖形用戶界面(GUI)工具包swing中的面板容器類，包含在javax.swing 包中，可以進行嵌套，功能是對窗體中具有相同邏輯功能的組件進行組合，是一種輕量級容器，可以加入到JFrame窗體中。。
JLabel– JLabel 對象可以顯示文本、圖像或同時顯示二者。可以通過設置垂直和水平對齊方式，指定標簽顯示區中標簽內容在何處對齊。默認情況下，標簽在其顯示區內垂直居中對齊。默認情況下，只顯示文本的標簽是開始邊對齊；而只顯示圖像的標簽則水平居中對齊。
JTextField–一個輕量級組件，它允許編輯單行文本。
JPasswordField– 允許我們輸入了一行字像輸入框，但隱藏星號(*) 或點創建密碼(密碼)
JButton– JButton 類的實例。用於創建按鈕類似實例中的 "Login"。
9. java注冊登錄
不清楚LZ的意思，不連接資料庫么？