org.apache.kafka.common.MessageFormatter 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;
import java.io.Closeable;
import java.io.PrintStream;
import java.util.Map;
import java.util.Properties;
import org.apache.kafka.clients.consumer.ConsumerRecord;
/**
* This interface allows to define Formatters that can be used to parse and format records read by a
* Consumer instance for display.
* The kafka-console-consumer has built-in support for MessageFormatter, via the --formatter flag.
*
* Kafka provides a few implementations to display records of internal topics such as __consumer_offsets,
* __transaction_state and the MirrorMaker2 topics.
*
*/
public interface MessageFormatter extends Configurable, Closeable {
/**
* Initialises the MessageFormatter
* @param props Properties to configure the formatter
* @deprecated Use {@link #configure(Map)} instead, this method is for backward compatibility with the older Formatter interface
*/
@Deprecated
default public void init(Properties props) {}
/**
* Configures the MessageFormatter
* @param configs Map to configure the formatter
*/
default public void configure(Map configs) {
Properties properties = new Properties();
properties.putAll(configs);
init(properties);
}
/**
* Parses and formats a record for display
* @param consumerRecord the record to format
* @param output the print stream used to output the record
*/
public void writeTo(ConsumerRecord consumerRecord, PrintStream output);
/**
* Closes the formatter
*/
default public void close() {}
}