flink-formats/flink-avro/src/main/java/org/apache/flink/formats/avro/typeutils/SerializableAvroSchema.java

/*
 * 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.flink.formats.avro.typeutils;

import org.apache.flink.annotation.Internal;

import org.apache.avro.Schema;
import org.apache.avro.Schema.Parser;
import org.apache.avro.reflect.Nullable;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

/**
 * A wrapper for Avro {@link Schema}, that is Java serializable.
 */
@Internal
final class SerializableAvroSchema implements Serializable {

	private static final long serialVersionUID = 1;

	private transient @Nullable Schema schema;

	SerializableAvroSchema() {
	}

	SerializableAvroSchema(Schema schema) {
		this.schema = schema;
	}

	Schema getAvroSchema() {
		return schema;
	}

	private void writeObject(ObjectOutputStream oos) throws IOException {
		if (schema == null) {
			oos.writeBoolean(false);
		}
		else {
			oos.writeBoolean(true);
			oos.writeUTF(schema.toString(false));
		}
	}

	private void readObject(ObjectInputStream ois) throws ClassNotFoundException, IOException {
		if (ois.readBoolean()) {
			String schema = ois.readUTF();
			this.schema = new Parser().parse(schema);
		}
		else {
			this.schema = null;
		}
	}
}