| /* |
| * 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.samza.operators.functions; |
| |
| import org.apache.samza.annotation.InterfaceStability; |
| |
| |
| /** |
| * A function that can be closed after its execution. |
| * <p> |
| * Implement {@link #close()} to free resources used during the execution of the function, clean up state etc. |
| * <p> |
| * Order of finalization: {@link ClosableFunction}s are closed in the reverse topological order of operators in the |
| * {@link org.apache.samza.application.descriptors.StreamApplicationDescriptor}. For any two operators A and B in the |
| * graph, if operator B consumes results from operator A, then operator B is guaranteed to be closed before operator A. |
| * |
| */ |
| @InterfaceStability.Evolving |
| public interface ClosableFunction { |
| /** |
| * Frees any resource acquired by the operators in {@link InitableFunction} |
| */ |
| default void close() {} |
| } |
