javaWeb登陆注册页面

时间 2020-07-26

标签 javaweb 登陆注册页面栏目 Java 繁體版

原文原文链接

简单的登录注册页面前端

1.配置JDBC驱动链接数据库java

2. 配置struts2框架mysql

3. 利用1 2完成登陆页面，注意作到不耦合，即servlet Api和控制器彻底脱离）web

4. 利用1 2 制做注册页面，判断数据库是否存在注册帐号，若存在，则提示帐号存在，不存在则跳转注册成功页面sql

建立项目命名为chapter04 找到下载好的JDBC驱动jar文件复制粘贴到WebRoot-WEB-INF下的lib文件夹下，如图数据库

2配置struts2框架apache

在网上下载struts2框架，打开struts2文件夹中的lib找到以下的jar文件一样复制到WebRoot-WEB-INF下的lib文件夹下app

接下来在web.xml中配置前端控制器，具体代码以下框架

<filter>
  <filter-name>struts2</filter-name>
  <filter-class> org.apache.struts2.dispatcher.filter.StrutsPrepareAndExecuteFilter</filter-class>
  </filter>
  <filter-mapping>
  <filter-name>struts2</filter-name>
  <url-pattern>/*</url-pattern>
  </filter-mapping>

最后在Struts.xml中配置Action分发给对应的JSP 代码以下jsp

<struts>
   <constant name="struts.devMode" value="true"></constant>
   <package name="loginpkg" extends="struts-default" namespace="/">
   <action name="succes" class="loginAction.login" method="logins">
   <result name="succes">/succes.jsp</result>
     <result name="defeat">/defeat.jsp</result>
   </action>
   <action name="register" class="loginAction.register" method="registers">
   <result name="succes">/index.jsp</result>
   <result name="defeat">/defeat.jsp</result>
   </action>
   </package>
</struts>

JSP页面的有 index.jsp register.jsp defeat.jsp success.jsp对应分别是首页注册页面失败跳转页面成功登陆页面这里只介绍index.jsp界面，其余比较简单本身写 index.jsp代码以下

<body>
    <form action="/chapter04/succes">
    用户:<input name="name" style="margin-left:10px;"><br>
    密码:<input name="password" style="margin-left:10px;"><br>
    <input type="submit" value="登陆" style="position: absolute; left: 50px; top:60px;">
    </form>
  
    <a style="position: absolute; left: 110px; top:60px;" href='/chapter04/register.jsp' >注册</a>
   
  </body>

在src下建立一个包名为jdbcDAO ，在包内建立名为Conn的jdbc链接数据库类，代码以下；

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class Conn {
public static Connection con;
  public static Connection getconnection() {
      try {
        Class.forName("com.mysql.jdbc.Driver");
    } catch (ClassNotFoundException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
      String url="jdbc:mysql://127.0.0.1:3306/userdb?characterEncoding=utf8";
      String user="root";
      String password="123456";
      try {
        con=DriverManager.getConnection(url, user, password);
    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return con}

新建查询数据库功能类 read 代码以下

package jdbcDAO;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.mysql.jdbc.PreparedStatement;

public class read {
  
    public static boolean isCheck(String name,String password){
        Connection con=Conn.getconnection();
        String sql="select * from user";
        PreparedStatement ps=null;
        ResultSet rs=null;
        try {
            ps=(PreparedStatement) con.prepareStatement(sql);
            rs=ps.executeQuery();
            while(rs.next()){
                String name1=rs.getString("name");
                String password1=rs.getString("password");
                if(name1.equals(name)&&password1.equals(password)){
                    return true;
                    
                }
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return false;
        
    }
    public static boolean isCheck1(String name){
        Connection con=Conn.getconnection();
        String sql="select * from user";
        PreparedStatement ps=null;
        ResultSet rs=null;
        try {
            ps=(PreparedStatement) con.prepareStatement(sql);
            rs=ps.executeQuery();
            while(rs.next()){
                String name1=rs.getString("name");
                
                if(name1.equals(name)){
                    return true;
                    
                }
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return false;
        
    }
}

建立添加用户功能类 Add代码以下

package jdbcDAO;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.mysql.jdbc.PreparedStatement;

public class Add {
  
    public static boolean Adds(String name,String password){
    Connection con=Conn.getconnection();
    boolean falg=false;
    PreparedStatement ps=null;
    String sql="insert into user(name,password)values(?,?)";
    try {
        ps=(PreparedStatement) con.prepareStatement(sql);
        ps.setString(1, name);
        ps.setString(2, password);
        int i=ps.executeUpdate();
        if(i==1){
            falg=true;
        }
    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return falg;

建立longAction包

在longAction包中建立两个类login和register类

login类代码以下

package loginAction;

import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.Servlet;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.config.entities.ActionConfig;

import jdbcDAO.read;
import userBean.User;

public class login extends ActionSupport {
private String name;
private String password;
private boolean falg=false;

    private static final long serialVersionUID = 1L;

    public String logins(){
        ServletActionContext sac=null;
        name=sac.getRequest().getParameter("name");
       password=sac.getRequest().getParameter("password");
        falg=read.isCheck(name, password);
            if(falg){
                return "succes";
    
            }else{
                return "defeat";
            }
        
        
    }
}

Register类代码以下

package loginAction;

import org.apache.struts2.ServletActionContext;

import jdbcDAO.Add;
import jdbcDAO.read;

public class register {
private boolean falg=false;
private String name;
private String password;
    public String registers(){
        ServletActionContext sac=null;
        name=sac.getRequest().getParameter("name");
       password=sac.getRequest().getParameter("password");
      
        falg=read.isCheck1(name); //真
        if(!falg){
            falg=Add.Adds(name, password);
            if(falg){
            
                return "succes";
            }
            else{
                
                
                return "defeat";
            }

        }else{
            return "defeat";
        }
    }
}