简单的get/post服务实现方式

　　项目中需要发布一个简单的接口，可以用前期提到的dubbo+rest框架来实现，但当功能需求不大时，可以使用一些简单的方式来提供服务。本篇持续更新，不断积累遇到的一些新的发布方法。

• Jersey

　　先来一个官网的地址：https://jersey.java.net/documentation/latest/。这里只是简单尝试它的服务提供方式，给出GET/POST的服务发布实例。后期再对其进行深入学习并总结。

        <!-- https://mvnrepository.com/artifact/asm/asm -->
        <dependency>
            <groupId>asm</groupId>
            <artifactId>asm</artifactId>
            <version>3.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.sun.jersey/jersey-client -->
        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-client</artifactId>
            <version>1.17.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.sun.jersey/jersey-server -->
        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-server</artifactId>
            <version>1.17.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.sun.jersey/jersey-core -->
        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-core</artifactId>
            <version>1.17.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.sun.jersey/jersey-servlet -->
        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-servlet</artifactId>
            <version>1.17.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/javax.ws.rs/jsr311-api -->
        <dependency>
            <groupId>javax.ws.rs</groupId>
            <artifactId>jsr311-api</artifactId>
            <version>1.1.1</version>
        </dependency>

　　从它的依赖中可以看到，Jersey提供了专门的服务器端与客户端的依赖，实际上，它的核心也就是核心服务器，核心客户端以及集成。

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.5"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee">
    <a href="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
        http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    </a>
    <display-name>RESTfulWS</display-name>
    <servlet>
        <servlet-name>Jersey REST Service</servlet-name>
        <servlet-class>
            com.sun.jersey.spi.container.servlet.ServletContainer
        </servlet-class>
        <init-param>
            <param-name>
                com.sun.jersey.config.property.packages
            </param-name>
            <param-value>com.changhong.test</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>Jersey REST Service</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>
</web-app>

　　注意初始化参数中的包名。

　　提供服务的类中：

@Path("recommend")
public class Recommend {

    private static Logger log = LoggerFactory.getLogger(Recommend.class);

    @GET
    @Path("/together/{json}")
    @Produces(MediaType.TEXT_XML)
    public String userName(@PathParam("json") String i) {
        ......  
    }
}

　　这里给出的GET也可以换成POST，但此配置下参数{json}都只能在url中进行提交，对于简单的业务，可以采用该种方式。但如果需要传入更为复杂的参数，如json等，就需要其它的配置。

• spring MVC

　　这里也只是给出几个实例，以及配置方法，其原理有待深入学习。

　　首先给出实际工程中，所用到的依赖：

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-aop -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.8.3</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.8.3</version>
        </dependency>

　　其次是/WEB-INF/目录下的一些配置文件

　　web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    version="3.0">
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
    <display-name>ChiqAlgTest</display-name>
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            classpath*:applicationContext.xml
        </param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    <servlet>
        <servlet-name>springServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/spring-mvc.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    <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>
    <servlet-mapping>
        <servlet-name>default</servlet-name>
        <url-pattern>*.css</url-pattern>
    </servlet-mapping>
</web-app>

　　spring-mvc.xml，其中包含了一些其它的常用配置

<?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:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:task="http://www.springframework.org/schema/task"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
        http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.2.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

    <!-- 自动扫描且只扫描@Controller -->
    <context:component-scan base-package="com.algo.test.controller"
        use-default-filters="false">
        <context:include-filter type="annotation"
            expression="org.springframework.stereotype.Controller" />
    </context:component-scan>

    <mvc:annotation-driven />

    <!-- 将无法mapping到Controller的path交给default servlet handler处理 -->
    <mvc:default-servlet-handler />
    <!-- 定义JSP文件的位置 -->
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/" />
        <property name="suffix" value=".jsp" />
    </bean>
    <mvc:resources location="/css/**" mapping="/css/**" />
    <mvc:default-servlet-handler />
    <!-- 支持response的body的json数据格式转换 begin -->
    <bean
        class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <ref bean="mappingJacksonHttpMessageConverter" />
            </list>
        </property>
    </bean>
    <bean id="mappingJacksonHttpMessageConverter"
        class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
        <property name="supportedMediaTypes">
            <list>
                <value>application/json;charset=UTF-8</value>
            </list>
        </property>
    </bean>
    <!-- end -->
    <!-- SpringMVC上传文件时，需要配置MultipartResolver处理器 -->
    <bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="UTF-8" />
        <!-- 指定所上传文件的总大小不能超过00。注意maxUploadSize属性的限制不是针对单个文件，而是所有文件的容量之和 -->
        <property name="maxUploadSize" value="20000000" />
    </bean>
</beans>

　　发布服务的类中设置相关注解，对请求路径，方式与传入参数进行限制：

　　get/传入String

@RestController
@RequestMapping("/recommend")
public class RestDemo {
    @GetMapping("/together/{param}")
    public JSONObject getData(@PathVariable("param") String i) {
        ...
    }
}

　　post/传入String

@RestController
@RequestMapping("/recommend")
public class RestDemo {
    @PostMapping("/together")
    public JSONObject getData(@RequestBody String i) {
    }
}

　　post/传入json并转化为bean

@RestController 
@RequestMapping("/recommend") 
public class RestDemo {
    @PostMapping("/togetherJson")
    public String getData(@RequestBody Message msg) {
        return msg.toString();
    }
}

　　给出最后一个请求的结果：

url:http://localhost:8080/ChiqAlgTest/recommend/togetherJson
body:{"mac":"123"}
response:Message [mac=123, p_bid=null, liv_pty=null, vid_pty=null, rule_view=null, param_view=null, fmt=null, rule=null]