Java tutorial
/** * Copyright (C) 2009-2012 the original author or authors. * See the notice.md file distributed with this work for additional * information regarding copyright ownership. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.fusesource.restygwt.examples.server; import java.io.IOException; import java.io.StringWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.node.JsonNodeFactory; import com.fasterxml.jackson.databind.node.ObjectNode; import org.fusesource.restygwt.client.Resource; /** * A simple server that serves JSON Data without constructing a Java Object. * * @author <a href="http://hiramchirino.com">Hiram Chirino</a> */ public class GreetingServlet extends HttpServlet { private static final long serialVersionUID = -5364009274470240594L; private static final String helloWorldJson = "{\"greeting\":\"Hello World\"}"; @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { System.out.println("Sending Hello World"); try { ObjectMapper mapper = new ObjectMapper(); JsonNode helloJsonNode = mapper.readTree(helloWorldJson); mapper.writeValue(resp.getOutputStream(), helloJsonNode); } catch (Throwable e) { e.printStackTrace(); } finally { System.out.flush(); System.err.flush(); } } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { System.out.println("Creating custom greeting."); try { ObjectMapper mapper = new ObjectMapper(); ObjectNode nameObject = mapper.readValue(req.getInputStream(), ObjectNode.class); String name = nameObject.get("name").asText(); String greeting = "Hello " + name; ObjectNode resultObject = new ObjectNode(JsonNodeFactory.instance); resultObject.put("greeting", greeting); mapper.writeValue(resp.getOutputStream(), resultObject); } catch (Throwable e) { e.printStackTrace(); } finally { System.out.flush(); System.err.flush(); } } }