2020.11.26收获

实现多用户登录

userSevlet.java

package servlet;

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

import bean.userbean;;

public class userServlet {
    private Connection conn;
    private PreparedStatement pstmt;

    @SuppressWarnings("static-access")
    public userServlet() {
        conn = new util.DBUtil().getConn();
    }

    public boolean Hefa1(userbean user) {
        try {
            pstmt = conn.prepareStatement(
                    "select * from usertable where user= '" + user.getUser() + "' and password=? and job=?");
            /* pstmt.setString(1, user.getUser()); */
            System.out.println(user.getUser());
            pstmt.setString(1, user.getPassword());
            pstmt.setString(2, user.job1);
            ResultSet rs = pstmt.executeQuery();
            if (rs.next())
                return true;
            else
                return false;
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return false;
        }
    }

    public boolean Hefa2(userbean user) {
        try {
            pstmt = conn.prepareStatement(
                    "select * from usertable where user= '" + user.getUser() + "' and password=? and  job=?");
            /* pstmt.setString(1, user.getUser()); */
            pstmt.setString(1, user.getPassword());
            pstmt.setString(2, user.job2);
            ResultSet rs = pstmt.executeQuery();
            if (rs.next())
                return true;
            else
                return false;
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return false;
        }
    }

}

userbean.java

package bean;

public class userbean {
private String user;
private String password;
public String job1="管理员";
public String job2="读者";

public String getUser() {
    return user;
}
public void setUser(String user) {
    this.user = user;
}
public String getPassword() {
    return password;
}
public void setPassword(String password) {
    this.password = password;
}



}

<%@ page  language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>登陆</title>
<style type="text/css">
.header {
    height: 100px;
    background-color: pink;
    font-family:楷体;
}

.a {
    margin-left: 20px;
    margin-top: 80px;
    text-align: center;
    font-family:楷体;
}

.button {
    background-color: pink;
    border: none;
    height: 40px;
     80px;
    font-family:楷体;
}
</style>
</head>
<body>
    <h1 class="header" style="text-align: center;padding-top: 40px">图书管理系统</h1>
    <h2 style="color: blue; text-align: center; font-family:楷体;padding-top: 40px">登陆</h2>
    <form action="check.jsp" method="get" onsubmit="return check()">
        <table border="0" style="align: center; margin: auto;">
            <div class="a">
                用户名： <input type="text" name="user" id="user">
            </div>
            <div class="a">
                &nbsp;&nbsp;密码： &nbsp;&nbsp;<input type="password" name="password"
                    id="password">
            </div>
            <div class="a">
                <button type="submit" class="button">登陆</button>
            </div>
        </table>
    </form>
</body>
<script type="text/javascript">
function check()
{
    var user=document.getElementById("user");
    var password=document.getElementById("password");
    if(user.value==""||mima.value=="")
        {
        alert("请把信息填写完整！");
        return false;
        }
}
</script>
</html>

check.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Insert title here</title>
</head>
<jsp:useBean id="a" class="bean.userbean"></jsp:useBean>
<jsp:useBean id="b" class="servlet.userServlet"></jsp:useBean>
<jsp:setProperty property="*" name="a" />
<body>

    <%
    request.setCharacterEncoding("utf-8");
    response.setContentType("text/html;charset=UTF-8");
    System.out.println(request.getParameter("user"));
    
        if (b.Hefa1(a)) {
    %>
    <jsp:forward page="guanliyuan.jsp"></jsp:forward>
    <%
        } else if (b.Hefa2(a)) {
            session.setAttribute("user", a);
            System.out.println(a.getUser());
    %>
    <jsp:forward page="reader.jsp"></jsp:forward>
    <%
        }
        else {
            
    %>

    <jsp:forward page="login.jsp"></jsp:forward>
    <%
        }
    %>
</body>
</html>