| /* |
| * 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.tephra.coprocessor; |
| |
| import com.google.common.base.Supplier; |
| import com.google.common.util.concurrent.Service; |
| |
| /** |
| * Provides ability to get and release objects |
| * |
| * @param <T> type of the object supplied |
| */ |
| public interface CacheSupplier<T extends Service> extends Supplier<T> { |
| |
| /** |
| * @return Get an instance of T and if it is the first call, then the service will be started. Subsequent calls |
| * will get a reference to the same instance |
| */ |
| @Override |
| T get(); |
| |
| /** |
| * Release the object obtained through {code Supplier#get()}. If this is the last release call, then the service will |
| * be stopped. |
| */ |
| void release(); |
| } |