{
  "author": "vijay",
  "created": "2016-10-28T14:55:55.273+05:37",
  "message": "RestServicedsfdsfsdfsdf"
}

import java.util.List;
import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.PUT;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;

@Path("/messages")
public class MessageResource {
    MessageService msgService = new MessageService();

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public List<Message> getMessages() {
        return msgService.getAllMessages();
    }

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    @Path("/{messageId}")
    public Message getMessage(@PathParam("messageId")long messageId) {
        return msgService.getMessage(messageId);
    }
    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public Message addMessage(Message message) {
        return msgService.addMessage(message);
    }
    @PUT
    @Path("/{messageId}")
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public Message updateMesage(@PathParam ("messageId") long id, Message message) {
        message.setId(id);
        return msgService.updateMessage(message);
    }

}

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public class MessageService {

    private Map<Long, Message> messages = MesaageDataBase.getMessages();

    public MessageService() {
        messages.put(1L, new Message(1232, "RestService", "vijay"));
        messages.put(2L, new Message(1233, "RestServiceClient", "Ashok"));
    }

    public List<Message> getAllMessages() {

        return new ArrayList<Message>(messages.values());
    }

    public Message getMessage(long id) {
        return messages.get(id);
    }

    public Message addMessage(Message message) {
        message.setId(messages.size() +1);
        messages.put(message.getId(), message);
        return message;
    }

    public Message updateMessage(Message message) {
        if(message.getId() <= 0) {
            return null;
        }
        messages.put(message.getId(), message);
        return message;
    }

    public Message removeMessage(Long id) {
        return messages.remove(id);
    }

}