jstl.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%--if--%>
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %><%--格式化日期--%>
<html>
<head>
<title>Title</title>
</head>
<body>
<h1>首页</h1>
<c:if test="${empty user}">
<a href="${pageContext.request.contextPath}/login">登录</a>
</c:if>
<c:if test="${!empty user}">
<p>欢迎:<strong>${user.usr_name}</strong>访问</p><%--点操作符--%> <%-- []操作符：${user["usr_name"]}--%>
<a href="${pageContext.request.contextPath}/logout">退出</a>
<fmt:formatDate value="${birth}" pattern="yyyy-MM-dd" /> <%--格式化--%>
${birth} <%--未格式化--%>
</c:if>
</body>
</html>
LoginServlet.java
package servlet;
import entity.User;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.annotation.*;
import java.io.IOException;
import java.util.Date;
@WebServlet("/login")
public class LoginServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.getSession().setAttribute("user",new User(1,"张三","zs","123"));
request.getSession().setAttribute("birth",new Date());
response.sendRedirect(request.getContextPath()+"/jiaoxue/jstl.jsp");
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
}
LogoutServlet.java
package servlet;
import entity.User;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebServlet("/logout")
public class LogoutServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.getSession().removeAttribute("user");
request.getSession().removeAttribute("birth");
response.sendRedirect(request.getContextPath()+"/jiaoxue/jstl.jsp");
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
}
登录
退出回到第一张图
标签：Java,request,response,JSTL,IOException,import,15,servlet,javax From： https://www.cnblogs.com/oyww-2027/p/17664348.html