| /* |
| * 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.nifi.distributed.cache.client; |
| |
| import java.io.IOException; |
| |
| import org.apache.nifi.annotation.documentation.CapabilityDescription; |
| import org.apache.nifi.annotation.documentation.Tags; |
| import org.apache.nifi.controller.ControllerService; |
| |
| /** |
| * This interface defines an API that can be used for interacting with a |
| * Distributed Cache that functions similarly to a {@link java.util.Set Set}. |
| */ |
| @Tags({"distributed", "client", "cluster", "set", "cache"}) |
| @CapabilityDescription("Provides the ability to communicate with a DistributedSetCacheServer. This allows " |
| + "multiple nodes to coordinate state with a single remote entity.") |
| public interface DistributedSetCacheClient extends ControllerService { |
| |
| /** |
| * Adds the specified value to the cache, serializing the value with the |
| * given {@link Serializer}. |
| * |
| * @param <T> type |
| * @param value value |
| * @param serializer serializer |
| * @return true if the value was added to the cache, false if the value |
| * already existed in the cache |
| * |
| * @throws IOException if unable to communicate with the remote instance |
| */ |
| <T> boolean addIfAbsent(T value, Serializer<T> serializer) throws IOException; |
| |
| /** |
| * @param <T> type |
| * @param value value |
| * @param serializer serializer |
| * @return if the given value is present in the cache and if so returns |
| * <code>true</code>, else returns <code>false</code> |
| * |
| * @throws IOException if unable to communicate with the remote instance |
| */ |
| <T> boolean contains(T value, Serializer<T> serializer) throws IOException; |
| |
| /** |
| * Removes the given value from the cache, if it is present. |
| * |
| * @param <T> type |
| * @param value value |
| * @param serializer serializer |
| * @return <code>true</code> if the value is removed, <code>false</code> if |
| * the value did not exist in the cache |
| * @throws IOException ex |
| */ |
| <T> boolean remove(T value, Serializer<T> serializer) throws IOException; |
| |
| /** |
| * Attempts to notify the server that we are finished communicating with it |
| * and cleans up resources |
| * |
| * @throws java.io.IOException ex |
| */ |
| void close() throws IOException; |
| } |