Your use of @PathParam is incorrect. It does not follow these requirements as documented in the javadoc here. I believe you just want to POST the JSON entity. You can fix this in your resource method to accept JSON entity.
@Path("/hello")
public class Hello {
@POST
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public JSONObject sayPlainTextHello(JSONObject inputJsonObj) throws Exception {
String input = (String) inputJsonObj.get("input");
String output = "The input you sent is :" + input;
JSONObject outputJsonObj = new JSONObject();
outputJsonObj.put("output", output);
return outputJsonObj;
}
}
And, your client code should look like this:
ClientConfig config = new DefaultClientConfig();
Client client = Client.create(config);
client.addFilter(new LoggingFilter());
WebResource service = client.resource(getBaseURI());
JSONObject inputJsonObj = new JSONObject();
inputJsonObj.put("input", "Value");
System.out.println(service.path("rest").path("hello").accept(MediaType.APPLICATION_JSON).post(JSONObject.class, inputJsonObj));