Java透过Maven整合CXF和Spring以Json的数据格式实现Restful Web Service

本文介绍如何通过CXF和Spring实现Restful Web Service，数据传输格式使用Json。

首先配置maven的库依赖，对于具体的实现可以参见

Simple JAX-RS Web Service in Java with Spring and CXF

也可以参照

Apache CXF与Spring集成实现Soap Webservice与RESTFul WebService

以下的依赖中spring、CXF、jackson是必须的，其他的根据需要增删

<properties>
	<java-version>1.8</java-version>
	<org.springframework-version>4.1.6.RELEASE</org.springframework-version>
	<org.hibernateframework-version>4.3.10.Final</org.hibernateframework-version>
	<org.cxf-version>3.1.1</org.cxf-version>
	<org.jackson-version>2.5.4</org.jackson-version>
	<org.postgresql-version>9.4-1201-jdbc41</org.postgresql-version>
	<org.c3p0-version>0.9.5</org.c3p0-version>
</properties>

<!-- cxf rest -->
<dependency>
    <groupId>org.apache.cxf</groupId>
    <artifactId>cxf-rt-frontend-jaxrs</artifactId>
    <version>${org.cxf-version}</version>
</dependency>

<dependency>
	<groupId>javax.ws.rs</groupId>
	<artifactId>javax.ws.rs-api</artifactId>
	<version>2.0</version>
</dependency>

<!-- jackson -->
<dependency>
    <groupId>com.fasterxml.jackson.jaxrs</groupId>
    <artifactId>jackson-jaxrs-json-provider</artifactId>
    <version>${org.jackson-version}</version>
</dependency>

<!-- spring -->
 <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>${org.springframework-version}</version>
</dependency>
 
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>${org.springframework-version}</version>
</dependency>
 
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-orm</artifactId>
    <version>${org.springframework-version}</version>
    <type>jar</type>
    <scope>compile</scope>
</dependency>

<!-- hibernate -->
<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
    <version>${org.hibernateframework-version}</version>
</dependency>

<!-- c3p0 -->
<dependency>
    <groupId>com.mchange</groupId>
    <artifactId>c3p0</artifactId>
    <version>${org.c3p0-version}</version>
</dependency>

<!-- postgresql -->
<dependency>
    <groupId>org.postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <version>${org.postgresql-version}</version>
</dependency>

另外两个地方需要注意的是web.xml需要配置CXF的servlet

<servlet>
	<description>Apache CXF Endpoint</description>
	<display-name>cxf</display-name>
	<servlet-name>cxf</servlet-name>
	<servlet-class>org.apache.cxf.transport.servlet.CXFServlet</servlet-class>
	<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
	<servlet-name>cxf</servlet-name>
	<url-pattern>/services/*</url-pattern>
</servlet-mapping>

 spring的context（或者bean）配置文件中需要加上暴露出去的server信息

<import resource="classpath:META-INF/cxf/cxf.xml" />  

<import resource="classpath:META-INF/cxf/cxf-servlet.xml" /> 

<!-- restful -->
<bean id="jsonProvider" 
	class="com.fasterxml.jackson.jaxrs.json.JacksonJsonProvider"/>
	
<jaxrs:server id="artistrs" address="/artistrs">  
    <jaxrs:serviceBeans>  
        <ref bean="artistsServiceImpl" />  
    </jaxrs:serviceBeans>  
    <jaxrs:providers>  
        <ref bean="jsonProvider" />  
    </jaxrs:providers>  
</jaxrs:server>  

 此处json的处理非常平滑，并不需要额外的代码，只需要在xml中声明jsonProvider，另外在类接口中通过注解的方式声明HTTP的请求方式，数据传输格式。

@Consumes("application/json")
@Produces("application/json")
public interface ArtistService {
	@POST
	@Path("/getAllArtists/")
	public List<Artists> getAllArtists();
}

 具体的测试方式可以通过chrome的插件postman，或者直接写java（使用HttpClient）代码如下

CloseableHttpClient httpclient = HttpClients.createDefault();
HttpPost httpPost = new HttpPost("http://localhost:8080/ArticleWS/services/artistrs/getAllArtists/");
CloseableHttpResponse response2 = httpclient.execute(httpPost);

System.out.println(response2.getStatusLine());

for (Header h : response2.getAllHeaders()){
	System.out.println(h.getName() + "--" + h.getValue());
}

HttpEntity entity2 = response2.getEntity();

BufferedReader br = new BufferedReader(new InputStreamReader(entity2.getContent(),"UTF-8"));

String line;
while ((line = br.readLine())!=null)
		System.out.println(line);

// do something useful with the response body
// and ensure it is fully consumed
EntityUtils.consume(entity2);

response2.close();

 或者通过python console

>>> import requests
>>> resp = requests.post('http://localhost:8080/ArticleWS/services/artistrs/getAllArtists/')
>>> resp.status_code
>>> resp.content.decode()

 重点是URL路径<web root>/<cxf servlet url-pattern>/<jaxrs:server address>/<Interface Path>

其他相关文档

Developing RESTful Services using Apache CXF

JAX-RS and JAX-WS