Spring--REST

<?xmlversion="1.0"encoding="UTF-8"?>

<web-appversion="2.4"

xmlns="http://java.sun.com/xml/ns/j2ee"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee

'target='_blank'>http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">[/code]

<!--配置Spring核心控制器-->

<servlet>

<servlet-name>dispatcher</servlet-name>

<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

<init-param>

<param-name>contextConfigLocation</param-name>

<param-value>/WEB-INF/dispatcher.xml</param-value>

</init-param>

<load-on-startup>1</load-on-startup>

</servlet>


<servlet-mapping>

<servlet-name>dispatcher</servlet-name>

<url-pattern>*.do</url-pattern>

</servlet-mapping>


<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>


4、WEB-INF中的dispatcher.xml配置

<?xmlversion="1.0"encoding="UTF-8"?>

<beansxmlns="http://www.springframework.org/schema/beans"

xmlns:mvc="http://www.springframework.org/schema/mvc"

xmlns:context="http://www.springframework.org/schema/context"

xmlns:util="http://www.springframework.org/schema/util"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://www.springframework.org/schema/beans

'target='_blank'>http://www.springframework.org/schema/beans/spring-beans-3.0.xsd[/code]
'target='_blank'>http://www.springframework.org/schema/mvc[/code]
'target='_blank'>http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd[/code]
http://www.springframework.org/schema/context

'target='_blank'>http://www.springframework.org/schema/context/spring-context-3.0.xsd[/code]
'target='_blank'>http://www.springframework.org/schema/util[/code]
'target='_blank'>http://www.springframework.org/schema/util/spring-util-3.0.xsd">[/code]

<context:component-scanbase-package="com.hoo.*">

<!--忽略这个类-->

<context:exclude-filtertype="assignable"expression="com.hoo.client.RESTClient"/>

</context:component-scan>


<!--annotation的方法映射适配器-->

<beanid="handlerAdapter"class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>


<!--xml视图，XStreamMarshaller，可以转换任何形式的java对象-->

<beanname="xStreamMarshallingView"class="org.springframework.web.servlet.view.xml.MarshallingView">

<propertyname="marshaller">

<beanclass="org.springframework.oxm.xstream.XStreamMarshaller">

<!--为了初始化XStreamMarshaller，这个类会把我们接口中得到结果以XML文档形式展现出来-->

<propertyname="autodetectAnnotations"value="true"/>

</bean>

</property>

</bean>


<!--视图解析器，根据视图的名称newModelAndView(name)，在配置文件查找对应的bean配置-->

<beanclass="org.springframework.web.servlet.view.BeanNameViewResolver">

<propertyname="order"value="3"/>

</bean>


<!--annotation默认的方法映射适配器-->

<beanid="handlerMapping"class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">

<propertyname="order"value="1"/>

</bean>


</beans>


5、启动后，可以看到index.jsp没有出现异常或错误。那么当前SpringMVC的配置就成功了。


二、REST控制器实现
REST控制器主要完成CRUD操作，也就是对于http中的post、get、put、delete。

还有其他的操作，如head、options、trace。

具体代码：

packagecom.hoo.controller;


importorg.springframework.stereotype.Controller;

importorg.springframework.web.bind.annotation.PathVariable;

importorg.springframework.web.bind.annotation.RequestMapping;

importorg.springframework.web.bind.annotation.RequestMethod;

importorg.springframework.web.servlet.ModelAndView;


/**

*<b>function:</b>SpringMVCREST示例

*@authorhoojo

*@createDate2011-6-9上午11:34:08

*@fileRESTController.java

*@packagecom.hoo.controller

*@projectSpringRestWS

*@blog'target='_blank'>http://blog.csdn.net/IBM_hoojo[/code]
*@emailhoojo_@126.com

*@version1.0

*/

@RequestMapping("/restful")

@Controller

publicclassRESTController{


@RequestMapping(value="/show",method=RequestMethod.GET)

publicModelAndViewshow(){

System.out.println("show");

ModelAndViewmodel=newModelAndView("xStreamMarshallingView");

model.addObject("showmethod");

returnmodel;

}


@RequestMapping(value="/get/{id}",method=RequestMethod.GET)

publicModelAndViewgetUserById(@PathVariableStringid){

System.out.println("getUserById-"+id);

ModelAndViewmodel=newModelAndView("xStreamMarshallingView");

model.addObject("getUserByIdmethod-"+id);

returnmodel;

}


@RequestMapping(value="/add",method=RequestMethod.POST)

publicModelAndViewaddUser(Stringuser){

System.out.println("addUser-"+user);

ModelAndViewmodel=newModelAndView("xStreamMarshallingView");

model.addObject("addUsermethod-"+user);

returnmodel;

}


@RequestMapping(value="/edit",method=RequestMethod.PUT)

publicModelAndVieweditUser(Stringuser){

System.out.println("editUser-"+user);

ModelAndViewmodel=newModelAndView("xStreamMarshallingView");

model.addObject("editUsermethod-"+user);

returnmodel;

}


@RequestMapping(value="/remove/{id}",method=RequestMethod.DELETE)

publicModelAndViewremoveUser(@PathVariableStringid){

System.out.println("removeUser-"+id);

ModelAndViewmodel=newModelAndView("xStreamMarshallingView");

model.addObject("removeUsermethod-"+id);

returnmodel;

}

}


上面的方法对应的http操作：

/show->get查询

/get/id->get查询

/add->post添加

/edit->put修改

/remove/id->delete删除


在这个方法中，就可以看到RESTful风格的url资源标识

@RequestMapping(value="/get/{id}",method=RequestMethod.GET)

publicModelAndViewgetUserById(@PathVariableStringid){

System.out.println("getUserById-"+id);

ModelAndViewmodel=newModelAndView("xStreamMarshallingView");

model.addObject("getUserByIdmethod-"+id);

returnmodel;

}


value=”/get/{id}”就是url中包含get，并且带有id参数的get请求，就会执行这个方法。这个url在请求的时候，会通过Annotation的@PathVariable来将url中的id值设置到getUserById的参数中去。ModelAndView返回的视图是xStreamMarshallingView是一个xml视图，执行当前请求后，会显示一篇xml文档。文档的内容是添加到model中的值。


三、利用RestTemplate调用REST资源
代码如下：

packagecom.hoo.client;


importorg.springframework.beans.factory.annotation.Autowired;

importorg.springframework.stereotype.Component;

importorg.springframework.web.client.RestTemplate;


/**

*<b>function:</b>RestTemplate调用REST资源

*@authorhoojo

*@createDate2011-6-9上午11:56:16

*@fileRESTClient.java

*@packagecom.hoo.client

*@projectSpringRestWS

*@blog'target='_blank'>http://blog.csdn.net/IBM_hoojo[/code]
*@emailhoojo_@126.com

*@version1.0

*/

@Component

publicclassRESTClient{


@Autowired

privateRestTemplatetemplate;


privatefinalstaticStringurl="http://localhost:8080/SpringRestWS/restful/";


publicStringshow(){

returntemplate.getForObject(url+"show.do",String.class,newString[]{});

}


publicStringgetUserById(Stringid){

returntemplate.getForObject(url+"get/{id}.do",String.class,id);

}


publicStringaddUser(Stringuser){

returntemplate.postForObject(url+"add.do?user={user}",null,String.class,user);

}


publicStringeditUser(Stringuser){

template.put(url+"edit.do?user={user}",null,user);

returnuser;

}


publicStringremoveUser(Stringid){

template.delete(url+"/remove/{id}.do",id);

returnid;

}

}


RestTemplate的getForObject完成get请求、postForObject完成post请求、put对应的完成put请求、delete完成delete请求；还有execute可以执行任何请求的方法，需要你设置RequestMethod来指定当前请求类型。

RestTemplate.getForObject(Stringurl,Class<String>responseType,String...urlVariables)

参数url是http请求的地址，参数Class是请求响应返回后的数据的类型，最后一个参数是请求中需要设置的参数。

template.getForObject(url+"get/{id}.do",String.class,id);

如上面的参数是{id}，返回的是一个string类型，设置的参数是id。最后执行该方法会返回一个String类型的结果。

下面建立一个测试类，完成对RESTClient的测试。代码如下：

packagecom.hoo.client;


importorg.springframework.beans.factory.annotation.Autowired;

importorg.springframework.test.context.ContextConfiguration;

importorg.springframework.test.context.junit38.AbstractJUnit38SpringContextTests;


/**

*<b>function:</b>RESTClientTEST

*@authorhoojo

*@createDate2011-6-9下午03:50:21

*@fileRESTClientTest.java

*@packagecom.hoo.client

*@projectSpringRestWS

*@blog'target='_blank'>http://blog.csdn.net/IBM_hoojo[/code]
*@emailhoojo_@126.com

*@version1.0

*/

@ContextConfiguration("classpath:applicationContext-*.xml")

publicclassRESTClientTestextendsAbstractJUnit38SpringContextTests{


@Autowired

privateRESTClientclient;


publicvoidtestShow(){

System.out.println(client.show());

}


publicvoidtestGetUserById(){

System.out.println(client.getUserById("abc"));

}


publicvoidtestAddUser(){

System.out.println(client.addUser("jack"));

}


publicvoidtestEditUser(){

System.out.println(client.editUser("tom"));

}


publicvoidtestRemoveUser(){

System.out.println(client.removeUser("aabb"));

}

}


我们需要在src目录下添加applicationContext-beans.xml完成对restTemplate的配置。restTemplate需要配置MessageConvert将返回的xml文档进行转换，解析成JavaObject。

<?xmlversion="1.0"encoding="UTF-8"?>

<beansxmlns="http://www.springframework.org/schema/beans"

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

'target='_blank'>http://www.springframework.org/schema/beans/spring-beans-3.0.xsd[/code]
'target='_blank'>http://www.springframework.org/schema/context[/code]
'target='_blank'>http://www.springframework.org/schema/context/spring-context-3.0.xsd">[/code]

<context:component-scanbase-package="com.hoo.*"/>


<beanid="restTemplate"class="org.springframework.web.client.RestTemplate">

<propertyname="messageConverters">

<list>

<beanclass="org.springframework.http.converter.xml.MarshallingHttpMessageConverter">

<propertyname="marshaller"ref="xStreamMarshaller"/>

<propertyname="unmarshaller"ref="xStreamMarshaller"/>

</bean>

</list>

</property>

</bean>


<beanid="xStreamMarshaller"class="org.springframework.oxm.xstream.XStreamMarshaller">

<propertyname="annotatedClasses">

<array>

</array>

</property>

</bean>

</beans>


上面配置了xStreamMarshaller是和RESTController中的ModelAndView的view对应的。因为那边是用xStreamMarshaller进行编组的，所以RestTemplate这边也需要用它来解组。RestTemplate还指出其他的MarshallingHttpMessageConverter；