Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.apache.ode.jacob.soup.jackson; import java.io.IOException; import java.util.HashMap; import java.util.Map; import org.apache.ode.jacob.ChannelRef; import org.apache.ode.jacob.Message; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.core.JsonToken; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.DeserializationContext; import com.fasterxml.jackson.databind.deser.std.StdDeserializer; /** * Jackson deserializer for Message objects. * * @author Tammo van Lessen * */ public class MessageDeserializer extends StdDeserializer<Message> { private static final long serialVersionUID = 1L; private TypeReference<HashMap<String, Object>> mapTypeRef = new TypeReference<HashMap<String, Object>>() { }; protected MessageDeserializer() { super(Message.class); } @Override public Message deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException { long id = 0; String action = null; ChannelRef to = null; ChannelRef replyTo = null; Map<String, Object> headers = null; Object body = null; while (jp.nextToken() != JsonToken.END_OBJECT) { String fieldname = jp.getCurrentName(); if (jp.getCurrentToken() == JsonToken.FIELD_NAME) { // if we're not already on the field, advance by one. jp.nextToken(); } if ("id".equals(fieldname)) { id = jp.getLongValue(); } else if ("action".equals(fieldname)) { action = jp.getText(); } else if ("to".equals(fieldname)) { to = jp.readValueAs(ChannelRef.class); } else if ("replyTo".equals(fieldname)) { replyTo = jp.readValueAs(ChannelRef.class); } else if ("headers".equals(fieldname)) { headers = jp.readValueAs(mapTypeRef); } else if ("body".equals(fieldname)) { body = jp.readValueAs(Object.class); } } if (action == null) { throw ctxt.mappingException(Message.class); } if (to == null) { throw ctxt.mappingException(Message.class); } Message msg = new Message(to, replyTo, action); msg.setHeaders(headers); msg.setBody(body); msg.setId(id); return msg; } }