Parser.java

/**
 * Copyright 2012, 2013 Turn, 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.turn.shapeshifter;

import com.fasterxml.jackson.databind.JsonNode;
import com.google.protobuf.Message;

/**
 * This interface encapsulates the task of parsing a JSON node into a
 * protocol buffer {@link Message}.
 *
 * @author jsilland
 */
public interface Parser {

	/**
	 * Parses a JSON node into its corresponding message.
	 *
	 * Note: schemas only maintain the data relative to the protocol buffer's
	 * structure but know nothing of the generated Java type that resulted from
	 * the representation's compilation. This method is therefore unable to
	 * instantiate messages of the correct subclass. The returned object is
	 * however guaranteed to be fully compatible with said generated class and
	 * can be safely merged at construction time, e.g.:
	 *
	 * <pre> {@code
	 * Schema schema = Schema.of(MyProto.getDescriptorForType())
	 * Message message = schema.parse(jsonNode);
	 * MyProto instance = MyProto.newBuilder().mergeFrom(message).build();}</pre>
	 *
	 * @param node the root node to parse
	 */
	public Message parse(JsonNode node, ReadableSchemaRegistry registry) throws ParsingException;
}