org.apache.kafka.common.serialization.Deserializer Maven / Gradle / Ivy
/*
* 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.kafka.common.serialization;
import org.apache.kafka.common.header.Headers;
import org.apache.kafka.common.utils.Utils;
import java.io.Closeable;
import java.nio.ByteBuffer;
import java.util.Map;
/**
* An interface for converting bytes to objects.
*
* A class that implements this interface is expected to have a constructor with no parameters.
*
* Implement {@link org.apache.kafka.common.ClusterResourceListener} to receive cluster metadata once it's available. Please see the class documentation for ClusterResourceListener for more information.
*
* @param Type to be deserialized into.
*/
public interface Deserializer extends Closeable {
/**
* Configure this class.
* @param configs configs in key/value pairs
* @param isKey whether is for key or value
*/
default void configure(Map configs, boolean isKey) {
// intentionally left blank
}
/**
* Deserialize a record value from a byte array into a value or object.
* @param topic topic associated with the data
* @param data serialized bytes; may be null; implementations are recommended to handle null by returning a value or null rather than throwing an exception.
* @return deserialized typed data; may be null
*/
T deserialize(String topic, byte[] data);
/**
* Deserialize a record value from a byte array into a value or object.
* @param topic topic associated with the data
* @param headers headers associated with the record; may be empty.
* @param data serialized bytes; may be null; implementations are recommended to handle null by returning a value or null rather than throwing an exception.
* @return deserialized typed data; may be null
*/
default T deserialize(String topic, Headers headers, byte[] data) {
return deserialize(topic, data);
}
/**
* Deserialize a record value from a ByteBuffer into a value or object.
* @param topic topic associated with the data
* @param headers headers associated with the record; may be empty.
* @param data serialized ByteBuffer; may be null; implementations are recommended to handle null by returning a value or null rather than throwing an exception.
* @return deserialized typed data; may be null
*/
default T deserialize(String topic, Headers headers, ByteBuffer data) {
return deserialize(topic, headers, Utils.toNullableArray(data));
}
/**
* Close this deserializer.
*
* This method must be idempotent as it may be called multiple times.
*/
@Override
default void close() {
// intentionally left blank
}
}