在 Rest 服务中返回纯字符串不返回 json？

Question

I created the following rest methods in my rest based web service

@GET
@Produces("application/json")
@Path("plain")
public String getPlain()
{
    return "hello world";
}

@GET
@Produces("application/json")
@Path("wrapper")
public Response getWrapper()
{
    return Response.ok(new Object(){ public String data = "hello world";}).build();
}

When I call plain service, it returns a raw string hello world rather than a JSON formatted output. However, wrapping the string in an object returns the JSON {"data":"hello world"}

Why is it showing such a behaviour? How do I send the plain String as JSON?

Answer 1

I tried the above option, it does not work.

String result="hello world";
return result;

The reason why String is not getting auto-converted seems to be due to missing @XmlRootElement. Based on the docuementation in cxf http://cxf.apache.org/docs/jax-rs-data-bindings.html#JAX-RSDataBindings-HandlingJAXBbeanswithoutXmlRootElementannotations we need to use some jaxbElementClassMap. But unable to find further details.

Answer 2

I think these will give you what you need.

@GET
@Produces("application/json")
@Path("plain")
public String getPlain()
{
return JSONObject.quote("Hello World");
}

OR

@GET
@Produces("application/json")
@Path("plain")
public String getPlain()
{
return "\"Hello World\"";
}

OR

@GET
@Produces("application/json")
@Path("plain")
public char[] getPlain()
{
return "Hello World!".toCharArray();
}

Answer 3

Try this

@GET 
@Produces("application/json") 
@Path("plain") 
public String getPlain() 
{ 
String result= "hello world";
    return result;
} 

JSON needs a key-value pair.