Suppress wrapper object when serializing Java object into JSON using Jackson

Question

I have a web service that returns a list as JSON. It uses Jackson to map a List of Java POJOs into JSON. The problem is that the JSON representation has a wrapper object around

Answer 1

In a test mode when I run:

org.codehaus.jackson.map.ObjectMapper mapper = new org.codehaus.jackson.map.ObjectMapper();
String json = mapper.writeValueAsString( Arrays.asList("one","two","three","four","five") );
System.out.println(json);

returns:

["one","two","three","four","five"]

which is the behavior you are expecting right?

I could see that when I return this list via a Spring controller and let MappingJacksonJsonView handle transforming the list to a json, then yes there is a wrapper around it, which tells me that the MappingJacksonJsonView is the one adding the wrapper. One solution then would be to explicitly return the json from your controller, say:

    @RequestMapping(value = "/listnowrapper")
public @ResponseBody String listNoWrapper() throws Exception{       
    ObjectMapper mapper = new ObjectMapper();
    return mapper.writeValueAsString(Arrays.asList("one","two","three","four","five")); 
}