Spring MVC 4

Spring MVC 4

项目文件结构

pom.xml依赖

    <properties><endorsed.dir>${project.build.directory}/endorsed</endorsed.dir><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding></properties><dependencies>       <dependency><groupId>org.codehaus.jackson</groupId><artifactId>jackson-mapper-asl</artifactId><version>1.9.13</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-web</artifactId><version>4.2.5.RELEASE</version></dependency><dependency><groupId>org.apache.commons</groupId><artifactId>commons-lang3</artifactId><version>3.4</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>4.2.5.RELEASE</version></dependency><!-- JSTL --><dependency><groupId>javax.servlet</groupId><artifactId>jstl</artifactId><version>1.2</version><scope>runtime</scope></dependency><dependency><groupId>javax</groupId><artifactId>javaee-web-api</artifactId><version>7.0</version><scope>provided</scope></dependency></dependencies>

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:p="http://www.springframework.org/schema/p"xmlns:aop="http://www.springframework.org/schema/aop"xmlns:tx="http://www.springframework.org/schema/tx"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsdhttp://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsdhttp://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd">
</beans>

spring-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsdhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"><!-- springmvc 注解驱动 --><!-- 启动注解驱动的Spring MVC功能，注册请求url和注解POJO类方法的映射--> <mvc:annotation-driven/><!-- 扫描器 --><!-- 启动包扫描功能，以便注册带有@Controller、@Service、@repository、@Component等注解的类成为spring的bean --> <context:component-scan base-package="com"/><!-- 配置视图解析器 --><!-- 对模型视图名称的解析，在请求时模型视图名称添加前后缀 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"><!-- 前缀 --><property name="prefix" value="/view/"></property><!-- 后缀 --><property name="suffix" value=".jsp"></property></bean>
</beans>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"><context-param><param-name>contextConfigLocation</param-name><param-value>/WEB-INF/applicationContext.xml</param-value></context-param><listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener><!-- POST中文乱码过滤器 Servlet 3.0 新特性@WebFilter,@WebFilter是过滤器的注解，不需要在web.xml进行配置，不过话说还是配置好用<filter><filter-name>CharacterEncodingFilter</filter-name><filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class><init-param><param-name>encoding</param-name><param-value>utf-8</param-value></init-param></filter><filter-mapping><filter-name>CharacterEncodingFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping>--><servlet><servlet-name>spring</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><load-on-startup>1</load-on-startup></servlet><servlet-mapping><servlet-name>spring</servlet-name><url-pattern>/</url-pattern></servlet-mapping><session-config><session-timeout>30</session-timeout></session-config><welcome-file-list>  <welcome-file>index.html</welcome-file> </welcome-file-list>  
</web-app>

hello.java

/** To change this license header, choose License Headers in Project Properties.* To change this template file, choose Tools | Templates* and open the template in the editor.*/
package com.me.www;import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.codehaus.jackson.map.ObjectMapper;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.ModelAndView;/*
@Scope("##") : spring默认的Scope是单列模式(singleton),顾名思义,肯定是线程不安全的.  而@Scope("prototype")
可以保证每个请求都会创建一个新的实例,  还有几个参数: session  request@Scope("session")的意思就是,只要用户不退出,实例就一直存在,
request : 就是作用域换成了request
@Controller : 不多做解释 , 标注它为Controller
@RequestMapping :是一个用来处理请求地址映射的注解，可用于类或方法上。用于类上，表示类中的所有响应请求的方法都是   以该地址作为父路径。 比如现在访问getProducts方法的地址就是 :
http://localhost:8080/项目名/上面web.xml配置(api)/products/list*/
@Scope("prototype")
@Controller
@RequestMapping("/hello")
public class Hello {//使用HttpServletRequest获取@RequestMapping(value = "/listRequest")public String listRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {request.setAttribute("message", "helloWord>>>HttpServletRequest方式 by http://blog.csdn.net/unix21/");return "hello";}//http://localhost:8080/www/hello/testRequestParameter?name=admin&pass=123@RequestMapping(value = "/listRequestParameter")public String listRequestParameter(HttpServletRequest request, HttpServletResponse response) throws Exception {String name = request.getParameter("name");String pass = request.getParameter("pass");request.setAttribute("message", "helloWord>>>HttpServletRequestParameter方式 参数是name=" + name + " pass=" + pass + " by http://blog.csdn.net/unix21/");return "hello";}@RequestMapping(value = "/listModel")public String listModel(Model model) {model.addAttribute("message", "Hello World>>>Model方式 by http://blog.csdn.net/unix21/");return "hello";}@RequestMapping(value = "/list/{id}", method = RequestMethod.GET)public String listId(@PathVariable String id, HttpServletRequest request, HttpServletResponse response) throws Exception {request.setAttribute("message", "helloWord>>>HttpServletRequest方式 id=" + id + " by http://blog.csdn.net/unix21/");return "hello";}//需要注意参数名要和bean对应@RequestMapping(value = "/list/{id}/{name}", method = RequestMethod.GET)public String listIdName(Product pro, HttpServletRequest request, HttpServletResponse response) throws Exception {request.setAttribute("message", "Hello World>>> 多参数" + pro.getId() + "___" + pro.getName() + " by http://blog.csdn.net/unix21/");return "/product/info";}@RequestMapping(value = "/listModelAndView")//@RequestMapping(value="/list",method=RequestMethod.GET)public ModelAndView listModelAndView() {//1、收集参数//2、绑定参数到命令对象//3、调用业务对象//4、选择下一个页面ModelAndView mv = new ModelAndView();//添加模型数据 可以是任意的POJO对象mv.addObject("message", "Hello World>>>ModelAndView方式 by http://blog.csdn.net/unix21/");//设置逻辑视图名，视图解析器会根据该名字解析到具体的视图页面mv.setViewName("hello");return mv;}@RequestMapping(value = "/post", method = RequestMethod.POST)public String postData(Product pro, HttpServletRequest request, HttpServletResponse response) throws Exception {request.setAttribute("message", "Hello World>>> POST参数" + pro.getId() + "___" + pro.getName() + " by http://blog.csdn.net/unix21/");return "hello";}//将内容或对象作为 HTTP 响应正文返回，使用@ResponseBody将会跳过视图处理部分，而是调用适合HttpMessageConverter，将返回值写入输出流。@ResponseBody@RequestMapping("/1.json")public void getJSON(HttpServletRequest req, HttpServletResponse res) throws Exception {Map<String, Object> map = new HashMap<String, Object>();Product p1 = new Product();p1.setId(123);p1.setName("abc");Product p2 = new Product();p2.setId(456);p2.setName("def");map.put("p1", p1);map.put("p2", p2);//org.​codehaus.​jackson.​mapObjectMapper mapper = new ObjectMapper();PrintWriter pWriter = res.getWriter();pWriter.write(mapper.writeValueAsString(map));}/*@RequestMappingRequestMapping是一个用来处理请求地址映射的注解，可用于类或方法上。用于类上，表示类中的所有响应请求的方法都是以该地址作为父路径。RequestMapping注解有六个属性，下面我们把她分成三类进行说明。1、 value， method；value：     指定请求的实际地址，指定的地址可以是URI Template 模式（后面将会说明）；method：  指定请求的method类型， GET、POST、PUT、DELETE等；2、 consumes，produces；consumes： 指定处理请求的提交内容类型（Content-Type），例如application/json, text/html;produces:    指定返回的内容类型，仅当request请求头中的(Accept)类型中包含该指定类型才返回；3、 params，headers；params： 指定request中必须包含某些参数值是，才让该方法处理。headers： 指定request中必须包含某些指定的header值，才能让该方法处理请求。*/
}

Product.java

package com.me.www;public class Product {private String  name;private int  id;/*** @return the name*/public String getName() {return name;}/*** @param name the name to set*/public void setName(String name) {this.name = name;}/*** @return the id*/public int getId() {return id;}/*** @param id the id to set*/public void setId(int id) {this.id = id;}
}

hello.jsp

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE html>
<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Hello World</title></head><body><h1>Spring MVC加载成功</h1>${message}</body>
</html>

例如：http://localhost:8080/www/hello/list/123/abc

Post数据

<html><head><title>POST数据提交</title><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"></head><body><form action="http://localhost:8080/www/hello/post" method="post"><input type="text" name="id"/> <input type="text" name="name"/> <input type="submit"/></form>
</body>
</html>

输出json

post参数转码的另一种处理方法

@RequestMapping(value = "/post", method = RequestMethod.POST)public ModelAndView post(@RequestParam("username")String username) {username=StringUtil.encodeStr(username);    ModelAndView mv = new ModelAndView();mv.addObject("username", username);mv.setViewName("post");return mv;
}

    /*** ISO-8859-1转UTF-8 主要用于POST数据处理** @param str 需要转码的值*/public static String encodeStr(String str) {try {return new String(str.getBytes("ISO-8859-1"), "UTF-8");} catch (UnsupportedEncodingException e) {return null;}}

@RequestBody  

@Controller  
@RequestMapping(value = "/pets", method = RequestMethod.POST, consumes="application/json")  
public void addPet(@RequestBody Pet pet, Model model) {      // implementation omitted  
}

/

参考：

SpringMVC简单构造restful, 并返回json

@Scope("##") : spring默认的Scope是单列模式(singleton),顾名思义,肯定是线程不安全的.  而@Scope("prototype")
可以保证每个请求都会创建一个新的实例,  还有几个参数: session  request
@Scope("session")的意思就是,只要用户不退出,实例就一直存在,
request : 就是作用域换成了request
@Controller : 不多做解释 , 标注它为Controller
@RequestMapping :是一个用来处理请求地址映射的注解，可用于类或方法上。用于类上，表示类中的所有响应请求的方法都是   以该地址作为父路径。 比如现在访问getProducts方法的地址就是 :
http://localhost:8080/项目名/上面web.xml配置(api)/products/list/

@RequestMapping 用法详解之地址映射

@RequestMapping
RequestMapping是一个用来处理请求地址映射的注解，可用于类或方法上。用于类上，表示类中的所有响应请求的方法都是以该地址作为父路径。
RequestMapping注解有六个属性，下面我们把她分成三类进行说明。
1、 value， method；
value：     指定请求的实际地址，指定的地址可以是URI Template 模式（后面将会说明）；
method：  指定请求的method类型， GET、POST、PUT、DELETE等；


2、 consumes，produces；
consumes： 指定处理请求的提交内容类型（Content-Type），例如application/json, text/html;
produces:    指定返回的内容类型，仅当request请求头中的(Accept)类型中包含该指定类型才返回；


3、 params，headers；
params： 指定request中必须包含某些参数值是，才让该方法处理。
headers： 指定request中必须包含某些指定的header值，才能让该方法处理请求。

@RequestParam @RequestBody @PathVariable 等参数绑定注解详解