spring mvc: xml生成

spring mvc: xml生成

准备：

javax.xml.bind.annotation.XmlElement;

javax.xml.bind.annotation.XmlRootElement;

spring类：

org.springframework.web.bind.annotation.PathVariable;

org.springframework.web.bind.annotation.ResponseBody;

@PathVariable 映射 URL 绑定的占位符

• 带占位符的 URL 是 Spring3.0 新增的功能，该功能在SpringMVC 向 REST 目标挺进发展过程中具有里程碑的意义
• 通过 @PathVariable 可以将 URL 中占位符参数绑定到控制器处理方法的入参中：URL 中的 {xxx} 占位符可以通过@PathVariable(“xxx“) 绑定到操作方法的入参中。

//@PathVariable可以用来映射URL中的占位符到目标方法的参数中
@RequestMapping("/testPathVariable/{id}")
    public String testPathVariable(@PathVariable("id") Integer id)
    {
        System.out.println("testPathVariable:"+id);
        return SUCCESS;
    }

　　

@ResponseBody用法

作用:

• 该注解用于将Controller的方法返回的对象，根据HTTP Request Header的Accept的内容,通过适当的HttpMessageConverter转换为指定格式后，写入到Response对象的body数据区。

使用时机：

• 返回的数据不是html标签的页面，而是其他某种格式的数据时（如json、xml等）使用.

配置返回JSON和XML数据

• 添加jackson依赖

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.8.1</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.8.1</version>
</dependency>

　　

• 开启<mvc:annotation-driven />

• java代码为

@RequestMapping("/testResponseBody")
    public @ResponseBody
    Person testResponseBody() {
        Person p = new Person();
        p.setName("xiaohong");
        p.setAge(12);
        return p;
    }

　　Person类

@XmlRootElement(name = "Person")
public class Person {
    private String name;
    private int age;
    public String getName() { return name;    }
    @XmlElement
    public void setName(String name) { this.name = name;    }
    public int getAge() { return age;    }
    @XmlElement
    public void setAge(int age) { this.age = age;    }
}

　　

• Ajax代码

$.ajax({
    url: "testResponseBody",
    type: 'GET',
    headers: {
        Accept: "application/xml",
//        Accept:"application/json",
    },
    success: function(data, textStatus){
        console.log(data);
        alert(data);
    },
    error: function (data, textStatus, errorThrown) {
        console.log(data);
    },
        });

　　

分析

• 如果没有配置Person类的XML注解,那么只会JSON数据,无论Accept是什么,

• 如果配置了Person类的xml注解,那么如果Accept含有applicatin/xml, 就会返回xml数据.例如通过浏览器直接访问,浏览器的http request header appect字段一般都为
  Accept:text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8, 故返回XML数据.
  改accept: "application/json",即可返回JSON数据.

用此注解或者ResponseEntity等类似类, 会导致response header含有accept-charset这个字段,而这个字段对于响应头是没有用的,以下方法可以关掉

<mvc:annotation-driven>
        <mvc:async-support default-timeout="3000"/>
        <!-- utf-8编码 -->
        <mvc:message-converters register-defaults="true">
            <bean class="org.springframework.http.converter.StringHttpMessageConverter">
                <constructor-arg value="UTF-8"/>
                <property name="writeAcceptCharset" value="false"/>
            </bean>
        </mvc:message-converters>
    </mvc:annotation-driven>

　　

开始：

本例有三个配置文件：web.xml, applicationContent.xml, xml2-servlet.xml

访问地址：

http://localhost:8080/gugua3/user/bagayalu

项目： gugua3

包名：xml2

web.xml:

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

<!--配置文件路径-->
<context-param>
 	<param-name>contextConfigLocation</param-name>
	<param-value>/WEB-INF/applicationContext.xml</param-value>
</context-param>

<!-- 字符过滤器 -->
<filter>
   <filter-name>encodingFilter</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>encodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping> 

<!-- 监听转发 -->
<listener>
	<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<servlet>
    <servlet-name>xml2</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>xml2</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>    

</web-app>

　　

applicationContent.xml

<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/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">

<!-- 默认：注解映射支持 -->
<mvc:annotation-driven/>
<!-- 静态资源配置 -->
<mvc:resources location="/pages/**" mapping="/pages/"/>

<!-- 自动扫描包名,controller -->
<context:component-scan base-package="xml2"/>		

</beans>

　　

xml2-servlet.xml

<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/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">

</beans>

　　

User.java

package xml2;

import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class User {

	String name;
	Integer id;

	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}

}

　　

UserController.java

package xml2;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.PathVariable;

@Controller
@RequestMapping(value="/user")
public class UserController {

	@RequestMapping(value="{name}", method=RequestMethod.GET)
	public @ResponseBody User  getUser(@PathVariable String name)
	{
		User user = new User();
		user.setName(name);
		user.setId(10);
		return user;

	}
}