我在生成text响应是是没有问题的:
@Path("myresource")
public class MyResource {
@GET
@Produces("text/plain")
public String getIt() {
return "hello";
}
}
但在生成json时:
@Path("/test")
public class RestTest1 {
@GET
@Produces({ MediaType.APPLICATION_JSON })
public HashMap getClientedMessage() {
HashMap<String, String> map = new HashMap<String, String>();
map.put("abc", "def");
return map;
}
}
报了如下错误:
javax.ws.rs.WebApplicationException: com.sun.jersey.api.MessageException: A message body writer for Java class java.util.HashMap, and Java type class java.util.HashMap, and MIME media type application/json was not found.
经查,要点如下:
1.需要引入jersey-json类包,maven依赖如下:
<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-json</artifactId>
<version>1.18</version>
</dependency>
2.需要在web.xml中的servlet中添加以下的POJOMappingFeature参数:
<servlet>
<servlet-name>Jersey</servlet-name>
<servlet-class>com.sun.jersey.spi.spring.container.servlet.SpringServlet</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>com.example</param-value>
</init-param>
<init-param>
<param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>