001/* 002 * Copyright 2012-2018 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.boot.jdbc.metadata; 018 019import java.util.ArrayList; 020import java.util.Collection; 021import java.util.Collections; 022import java.util.List; 023 024import javax.sql.DataSource; 025 026/** 027 * A {@link DataSourcePoolMetadataProvider} implementation that returns the first 028 * {@link DataSourcePoolMetadata} that is found by one of its delegate. 029 * 030 * @author Stephane Nicoll 031 * @since 2.0.0 032 */ 033public class CompositeDataSourcePoolMetadataProvider 034 implements DataSourcePoolMetadataProvider { 035 036 private final List<DataSourcePoolMetadataProvider> providers; 037 038 /** 039 * Create a {@link CompositeDataSourcePoolMetadataProvider} instance with an initial 040 * collection of delegates to use. 041 * @param providers the data source pool metadata providers 042 */ 043 public CompositeDataSourcePoolMetadataProvider( 044 Collection<? extends DataSourcePoolMetadataProvider> providers) { 045 this.providers = (providers != null) 046 ? Collections.unmodifiableList(new ArrayList<>(providers)) 047 : Collections.emptyList(); 048 } 049 050 @Override 051 public DataSourcePoolMetadata getDataSourcePoolMetadata(DataSource dataSource) { 052 for (DataSourcePoolMetadataProvider provider : this.providers) { 053 DataSourcePoolMetadata metadata = provider 054 .getDataSourcePoolMetadata(dataSource); 055 if (metadata != null) { 056 return metadata; 057 } 058 } 059 return null; 060 } 061 062}