在springmvc 通过URL请求数据返回JSON时，报错 The resource identified by this request is only capable of generating responses with characteristics not acceptable according to the request “accept” headers.

问题原因为未在pom文件中引入json的转换包。
解决办法：
1、在pom.xml中添加json所需要的依赖

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-core</artifactId>
  <version>2.7.3</version>
</dependency>

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-databind</artifactId>
  <version>2.7.3</version>
</dependency>

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-annotations</artifactId>
  <version>2.7.3</version>
</dependency>

2、spring-mvc.xml 加入：

	<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>

配置后，成功返回：