JacksonUtil.java

/*
 * Copyright 2014 Fizzed, Inc.
 *
 * 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 com.fizzed.stork.launcher;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
import java.util.Iterator;

/**
 *
 * @author joelauer
 */
public class JacksonUtil {
    
    public static JsonNode merge(JsonNode mainNode, JsonNode updateNode) {
        Iterator<String> fieldNames = updateNode.fieldNames();
        while (fieldNames.hasNext()) {

            String fieldName = fieldNames.next();
            JsonNode jsonNode = mainNode.get(fieldName);
            // if field exists and is an embedded object
            if (jsonNode != null && jsonNode.isObject()) {
                merge(jsonNode, updateNode.get(fieldName));
            }
            else {
                if (mainNode instanceof ObjectNode) {
                    // Overwrite field
                    JsonNode value = updateNode.get(fieldName);
                    ((ObjectNode) mainNode).put(fieldName, value);
                }
            }
        }
        return mainNode;
    }
    
}