How to access a huge JSON coming (from a spring RESTful Service) in a spring MVC app using RestTemplate - web-services

Question

My Spring RESTful web service is returning a JSON form of-
[{"key1":"value1","key2":"value2","key3":"value3"},{"key4":"value4","key5":"value5","key6":"value6"}]
Now when my spring MVC app, try to access it, to show in a JSP then Exception occurs saying-no suitable HttpMessageConverter found Please help me where I going wrong.Here is my code-
Inside #Controller class of my spring MVC app calling the RESTful service
//**com.songs.controllers.FrontSongController.java**
</*
author Rohit Tiwari
*/>
#RequestMapping(value="/alls",method=RequestMethod.POST)
public String getAllSongs(ModelMap md)
{
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON);
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<String> entity = new HttpEntity<String>(headers);
String url="http://localhost:7001/SongAppWS/songappWS/allsongsWS";
RestTemplate rt=new RestTemplate();
//SongResource.class is for representation on incoming JSON see below for its code
//This is the line no 48 that you will see in below browser logs
ResponseEntity<SongResource> listofallsongs=rt.exchange(url,HttpMethod.GET,entity, SongResource.class);
md.addAttribute("listname", "Songs available in the repository:");
System.out.println("Response Entity object= "+listofallsongs);
System.out.println("Response Entity body= "+listofallsongs.getBody().toString());
return "Sucess";
}
Inside config-servlet.xml of my spring MVC app calling the RESTful service
<context:component-scan base-package="com.songs.controllers" />
<mvc:annotation-driven />
<context:annotation-config/>
<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"></bean>
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"></bean>
<bean class="org.springframework.web.client.RestTemplate">
<property name="messageConverters">
<list>
<bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"/>
</list>
</property>
</bean>
<bean id="viewResolver" class="org.springframework.web.servlet.view.UrlBasedViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
</bean>
Inside SongResource.java of my spring MVC app, which I am trying to use for converting the coming JSON to my SongResource.class object, that my spring MVC app can use in a jsp
//**com.songs.service.resource.SongResource.java**
public class SongResource
{
private String name;
private String film;
private String singer;
public SongResource(String name,String film,String singer)
{
this.name=name;
this.film=film;
this.singer=singer;
}
//setter & getters of all above
}
On calling the spring REST service from my spring MVC app the browser is saying as below-
Error 500--Internal Server Error
org.springframework.web.client.RestClientException: Could not extract response: no suitable HttpMessageConverter found for response type [com.songs.service.resource.SongResource] and content type [application/json]
at org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java :77)
at org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:619)
at org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:1)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:446)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:401)
at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:377)
at com.songs.controllers.FrontSongController.getAllSongs(FrontSongController.java:48)
//and so on

Answer 1

Try this, hope it will help you
#RequestMapping(value="/alls",method=RequestMethod.POST)
public String getAllSongs(ModelMap md)
{
String url="http://localhost:7001/SongAppWS/songappWS/allsongsWS";
RestTemplate rt=new RestTemplate();
SongResource[] songRs = template.getForObject(url, SongResource[].class);
List<SongResource> songs = Arrays.asList(songRs);
md.addAttribute("listname", "Songs available in the repository:");
md.addAttribute("listValues", songs);
return "Sucess";
}