SpringMVC框架(3) —— 注解

项目结构

  • java
    • controller
      • SessionController.java(Java文件)
  • resources
    • springmvc.xml(springmvc配置文件)
  • webapp
    • WEB-INF
      • pages
        • success.jsp(web页面)
        • session.jsp(web页面)
      • web.xml(web配置文件)
    • index.jsp(web页面)
    • annotation.jsp(web页面)
  • pom.xml(maven项目配置文件)

maven项目配置文件

  • 配置maven项目需要的依赖
    • spring-context
    • spring-web
    • spring-webmvc
    • servlet-api
    • jsp-api

web配置文件

  • 前端控制器(DispatcherServlet)
    • 配置一个前端控制器(<servlet>)
      • 创建前端控制器时,加载Spring配置文件(<init-param>)
      • 启动服务器时,创建前端控制器(<\load-on-startup>)
    • 配置前端控制器的作用范围(<servlet-mapping>)
  • 过滤器(CharacterEncodingFilter)
    • 配置一个过滤器(<filter>)
      • 配置编码(<init-param>):解决中文乱码
    • 配置前端控制器的作用范围(<filter-mapping>)

springmvc配置文件

  • 导入名称空间(<beans xmlns="">)
  • 开启注解扫描(<context:component-scan base-package="">)
  • 配置视图解析器(InternalResourceViewResolver)
    • 配置前缀(prefix -> “/WEB-INF/pages”)
    • 配置后缀(suffix -> “.jsp”)
  • 开启SpringMVC注解支持(<mvc:annotation-driven>)

Java文件

  • 表现层

      • 添加进IoC核心容器(@Controller)
      • 设置请求映射(@RequestMapping())
        • 一级目录(path="")
        • 设置允许访问的请求方法(method="")
        • 设置必需的参数和参数值(params="")
          • 设置必需的请求头(headers="")
      • 设置Session域的键值对(@SessionAttributes())
    • 方法

      • 设置请求映射(@RequestMapping())
        • 二级目录(path="")
      • 返回值(return “success”;)
      • 参数列表(数据类型 请求参数名,数据类型 请求参数名)
        • Model:用于存储键值对至Request域
        • ModelMap:用于获取Request域中的键值对
        • SessionStatus:用于清空Session域中的键值对
      • 设置初始化方法(@ModelAttribute)
    • 方法参数

      • 获取请求参数(@RequestParam())

        • 二级目录:"/testRequestParam"
        • 请求地址:“anno/testRequestParam?name=cat”
      • 获取请求参数(@PathVariable())

        • 二级目录:"/testPathVariable/{name}"
        • 请求地址:“anno/testPathVariable/cat”
      • 获取请求体(@RequestBody)

      • 获取请求头(@RequestHeader)

      • 获取缓存(@CookieValue())

      • 获取底层Map集合的键值对(@ModelAttribute())

      • 设置Session域的键值对(@SessionAttributes())

JSP文件

  • 超链接(href=“一级目录/二级目录?请求参数=值&请求参数=值”)
  • 表单(<form action=“一级目录/二级目录” method=“post”>)

执行代码

  • 需求:在annotation.jsp页面,点击的超链接,跳转到success.jsp页面,并且在控制台输出请求消息

pom.xml

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>cn.water</groupId>
  <artifactId>section01_Introduction</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>section01_Introduction Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <!-- 版本锁定 -->
  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
    <spring.version>5.0.2.RELEASE</spring.version>
  </properties>

  <!-- 依赖注入 -->
  <dependencies>
    <!-- spring -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- spring-web -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- spring-webmvc -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- servlet -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>servlet-api</artifactId>
      <version>2.5</version>
      <scope>provided</scope>
    </dependency>
    <!-- jsp -->
    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.0</version>
      <scope>provided</scope>
    </dependency>
  </dependencies>

  <build>
    <finalName>section01_Introduction</finalName>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-war-plugin</artifactId>
          <version>3.2.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

web.xml

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>

  <!--   【Filter】   -->
  <filter>
    <!--   创建过滤器   -->
    <filter-name>characterEncodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <!--   配置编码   -->
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <!--   映射   -->
  <filter-mapping>
    <filter-name>characterEncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

  <!--   【Servlet】   -->
  <servlet>
    <!--   创建前端控制器   -->
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!--   创建前端控制器时,加载spring配置文件   -->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <!--   启动服务器时,创建前端控制器   -->
    <load-on-startup>1</load-on-startup>
  </servlet>
  <!--   映射   -->
  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

springmvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">


    <!-- 开启注解扫描 -->
    <context:component-scan base-package="cn.water"/>

    <!-- 视图解析器 -->
    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver" >
        <!-- 配置前缀 -->
        <property name="prefix" value="/WEB-INF/pages/"></property>
        <!-- 配置后缀 -->
        <property name="suffix" value=".jsp"></property>
    </bean>


    <!-- 开启springMVC框架注解支持 -->
    <mvc:annotation-driven />


</beans>

AnnotationController.java

package cn.water.controller;

import cn.water.domain.User;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.bind.support.SessionStatus;

import java.util.Map;

/**
 * @author Water
 * @date 2019/9/10 - 10:48
 */
@Controller
@RequestMapping("/anno")
/* 将键值对存储到session域 */
@SessionAttributes("message")
public class AnnotationController {

    /* 【获取请求参数】 */
    @RequestMapping("/testRequestParam")
    public String testRequestParam(@RequestParam(name = "name") String username ){
        System.out.println("请求参数:"+username);
        return "success";
    }

    /* 【获取请求参数】 */
    @RequestMapping("/testPathVariable/{name}")
    public String testPathVariable(@PathVariable(name = "name") String username ){
        System.out.println("请求参数:"+username);
        return "success";
    }

    /* 【获取请求体(GET请求方式没有请求体)】 */
    @RequestMapping("/testRequestBody")
    public String testRequestBody(@RequestBody String body ){
        System.out.println("请求体:"+body);
        return "success";
    }

    /* 【获取请求头】 */
    @RequestMapping("/testRequestHeader")
    public String testRequestHeader(@RequestHeader(value = "Accept") String header ){
        System.out.println("请求头:"+header);
        return "success";
    }

    /* 【Cookie】 */
    @RequestMapping("/testCookieValue")
    public String testCookieValue(@CookieValue(value = "JSESSIONID") String cookieValue ){
        System.out.println("Cookie:"+cookieValue);
        return "success";
    }

    /* 【ModelAttribute】 */
    /* 用于将表单提交的数据封装至JavaBean对象时,当时当数据不全时,使用ModelAttribute注释的方法将数据补全 */
//    [方法一]
//    @RequestMapping("/testModelAttribute")
//    public String testModelAttribute(User user){
//        System.out.println("testModelAttribute执行了...");
//        System.out.println(user);
//        return "success";
//    }
//    @ModelAttribute /* 先执行 */
//    public User ModelAttributeMethod(String name){
//        System.out.println("ModelAttributeMethod执行了...");
//        User user = new User();
//        user.setName(name);
//        user.setAge("11");
//        return user;
//    }
//    [方法二]
    @RequestMapping("/testModelAttribute")
    public String testModelAttribute(@ModelAttribute("user_name") User user){
        System.out.println("testModelAttribute执行了...");
        System.out.println(user);
        return "success";
    }
    /* 将User对象存储进底层的Map集合中 */
    @ModelAttribute /* 先执行 */
    public void ModelAttributeMethod(String username, Map<String,User> map){
        System.out.println("ModelAttributeMethod执行了...");
        User user = new User();
        user.setName(username);
        user.setAge("11");
        map.put("user_name",user);
    }



    @RequestMapping("testSessionAttributes")
    public String testSessionAttributes(Model model){
        /* 将键值对存储到request域 */
        model.addAttribute("message","Hello,Request Field!");
        return "session";
    }

    @RequestMapping("getSessionAttributes")
    public String getSessionAttributes(ModelMap modelMap){
        /* 获取Session域中的值 */
        Object message = modelMap.get("message");
        System.out.println(message);
        return "session";
    }

    @RequestMapping("removeSessionAttributes")
    public String removeSessionAttributes(SessionStatus sessionStatus){
        /* 清空Session域中的值 */
        sessionStatus.setComplete();
        return "session";
    }


}

index.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
    <h2><a href="controller/sayHello?username=cat">入门</a></h2>
    <hr>
    <h2><a href="parameters.jsp">参数绑定</a></h2>
    <hr>
    <h2><a href="annotation.jsp">注解</a></h2>
    <hr>
</body>
</html>

annotation.jsp

<%--
  Created by IntelliJ IDEA.
  User: Water
  Date: 2019/9/19
  Time: 14:28
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
    <%-- 请求参数 --%>
    <h3><a href="anno/testRequestParam?name=cat&name=dog&name=rat">获取 请求参数(RequestParam)</a></h3>
    <hr>

    <%-- 请求参数 --%>
    <%--<a href="anno/testRequestParam?name=cat">请点击</a>--%>
    <a href="anno/testPathVariable/cat">获取 请求参数(PathVariable)</a>     // "cat" <br>
    <a href="anno/testPathVariable/cat&dog">获取 请求参数(PathVariable)</a>     // "cat&dog"
    <hr>

    <%-- 请求体 --%>
    <form action="anno/testRequestBody" method="post">
        姓名:<input type="text" name="username" /><br/>
        密码:<input type="text" name="password" /><br/>
        金额:<input type="text" name="money" /><br/>
        <input type="submit" value="获取 请求体(RequestBody)">
    </form>
    <hr>

    <%-- 请求头 --%>
    <h3><a href="anno/testRequestHeader">获取 请求头(RequestHeader)</a></h3>
    <hr>

    <%-- 缓存 --%>
    <h3><a href="anno/testCookieValue">获取 缓存(CookieValue)</a></h3>
    <hr>

    <%-- ModelAttribute --%>
    <form action="anno/testModelAttribute" method="post">
        姓名:<input type="text" name="username" /><br/>
        <input type="submit" value="ModelAttribute">
    </form>
    <hr>

    <a href="anno/testSessionAttributes">设置,并在浏览器查看Request域和Session域中的message值</a><br>
    <a href="anno/getSessionAttributes">在控制台查看Session域中的message值</a><br>
    <a href="anno/removeSessionAttributes">删除,并在浏览器查看Session域中的message值</a><br>


</body>
</html>

success.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<h3>访问成功!!!</h3>

</body>
</html>

session.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
    <h1>Request域:</h1>${requestScope.message}<br>
    <h1>Session域:</h1>${sessionScope}
</body>
</html>

@RequestParam 请求参数

  • 发出请求
<a href="anno/testRequestParam?name=cat&name=dog&name=rat">获取 请求参数(RequestParam)</a>
  • 接收请求
@RequestMapping("/testRequestParam")
public String testRequestParam(@RequestParam(name = "name") String username ){
    System.out.println("请求参数:"+username);
    return "success";
}
  • 运行结果
请求参数:cat,dog,rat

@PathVariable 请求参数

  • 发出请求
<a href="anno/testPathVariable/cat">获取 请求参数(PathVariable)</a> <br>
<a href="anno/testPathVariable/cat&dog">获取 请求参数(PathVariable)</a>     
  • 接收请求
@RequestMapping("/testPathVariable/{name}")
public String testPathVariable(@PathVariable(name = "name") String username ){
    System.out.println("请求参数:"+username);
    return "success";
}
  • 运行结果
请求参数:cat
请求参数:cat&dog

@RequestBody 请求体

  • 发出请求
<form action="anno/testRequestBody" method="post">
    姓名:<input type="text" name="username" /><br/>
    密码:<input type="text" name="password" /><br/>
    金额:<input type="text" name="money" /><br/>
    <input type="submit" value="获取 请求体(RequestBody)">
</form>
  • 接收请求
/* 【GET请求方式没有请求体】 */
@RequestMapping("/testRequestBody")
public String testRequestBody(@RequestBody String body ){
    System.out.println("请求体:"+body);
    return "success";
}
  • 运行结果
请求体:username=cat&password=111&money=999

@RequestHeader 请求头

  • 发出请求
<a href="anno/testRequestHeader">获取 请求头(RequestHeader)</a>
  • 接收请求
@RequestMapping("/testRequestHeader")
public String testRequestHeader(@RequestHeader(value = "Accept") String header ){
    System.out.println("请求头:"+header);
    return "success";
}
  • 运行结果
请求头:text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3

@CookieValue 缓存

  • 发出请求
<a href="anno/testCookieValue">获取 缓存(CookieValue)</a>
  • 接收请求
@RequestMapping("/testCookieValue")
public String testCookieValue(@CookieValue(value = "JSESSIONID") String cookieValue ){
    System.out.println("Cookie:"+cookieValue);
    return "success";
}
  • 运行结果
Cookie:93E4FB2388E1A6249DA4552C947FE2C2

@ModelAttribute

  • 发出请求
<form action="anno/testModelAttribute" method="post">
    姓名:<input type="text" name="username" /><br/>
    <input type="submit" value="ModelAttribute">
</form>
  • 接收请求
@RequestMapping("/testModelAttribute")
    public String testModelAttribute(User user){
	System.out.println("testModelAttribute执行了...");
	System.out.println(user);
	return "success";
}

/* 直接返回User对象 */
@ModelAttribute /* 先执行 */
public User ModelAttributeMethod(String name){
    System.out.println("ModelAttributeMethod执行了...");
    User user = new User();
    user.setName(name);
    user.setAge("11");
    return user;
}
  • 运行结果
ModelAttributeMethod执行了...
testModelAttribute执行了...
User{name='cat', age='11'}

方法二

  • 接收请求
/* 将User对象存储进底层的Map集合中 */
@ModelAttribute
public void ModelAttributeMethod(String username, Map<String,User> map){
    System.out.println("ModelAttributeMethod执行了...");
    User user = new User();
    user.setName(username);
    user.setAge("11");
    map.put("user_name",user);
}

设置域

  • 发出请求
<a href="anno/testSessionAttributes">设置,并在浏览器查看Request域和Session域中的message值</a>
  • 接收请求
@RequestMapping("testSessionAttributes")
public String testSessionAttributes(Model model){
    /* 将键值对存储到request域 */
    model.addAttribute("message","Hello,Request Field!");
    return "session";
}
  • 响应页面
Request域:${requestScope.message}<br>
Session域:${sessionScope}
  • 响应结果
Request域:Hello,Request Field!
Session域:{message=Hello,Request Field!}

查看域

  • 发出请求
<a href="anno/getSessionAttributes">在控制台查看Session域中的message值</a>
  • 接收请求
@RequestMapping("getSessionAttributes")
public String getSessionAttributes(ModelMap modelMap){
    /* 获取Session域中的值 */
    Object message = modelMap.get("message");
    System.out.println(message);
    return "session";
}
  • 响应页面
Request域:${requestScope.message}<br>
Session域:${sessionScope}
  • 响应结果
Request域:Hello,Request Field!
Session域:{message=Hello,Request Field!}
  • 运行结果
Hello,Request Field!

删除域

  • 发出请求
<a href="anno/removeSessionAttributes">删除,并在浏览器查看Session域中的message值</a>
  • 接收请求
@RequestMapping("removeSessionAttributes")
public String removeSessionAttributes(SessionStatus sessionStatus){
    /* 清空Session域中的值 */
    sessionStatus.setComplete();
    return "session";
}
  • 响应页面
Request域:${requestScope.message}<br>
Session域:${sessionScope}
  • 响应结果
Request域:
Session域:{}
发布了68 篇原创文章 · 获赞 2 · 访问量 1904

猜你喜欢

转载自blog.csdn.net/qq_40981851/article/details/104206214