001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.mail.resolver; 018 019import org.apache.commons.mail.DataSourceResolver; 020 021import javax.activation.DataSource; 022import java.io.IOException; 023 024/** 025 * A composite data source resolver. It allows to resolve data sources coming from 026 * multiple locations such as the classpath, the file system or an URL. 027 * 028 * @since 1.3 029 */ 030public class DataSourceCompositeResolver extends DataSourceBaseResolver 031{ 032 /** the list of resolvers */ 033 private final DataSourceResolver[] dataSourceResolvers; 034 035 /** 036 * Constructor. 037 * 038 * @param dataSourceResolvers a list of of resolvers being used 039 */ 040 public DataSourceCompositeResolver(final DataSourceResolver[] dataSourceResolvers) 041 { 042 this.dataSourceResolvers = new DataSourceResolver[dataSourceResolvers.length]; 043 System.arraycopy(dataSourceResolvers, 0, this.dataSourceResolvers, 0, dataSourceResolvers.length); 044 } 045 046 /** 047 * Constructor. 048 * 049 * @param dataSourceResolvers a list of of resolvers being used 050 * @param isLenient shall we ignore resources not found or throw an exception? 051 */ 052 public DataSourceCompositeResolver(final DataSourceResolver[] dataSourceResolvers, final boolean isLenient) 053 { 054 super(isLenient); 055 this.dataSourceResolvers = new DataSourceResolver[dataSourceResolvers.length]; 056 System.arraycopy(dataSourceResolvers, 0, this.dataSourceResolvers, 0, dataSourceResolvers.length); 057 } 058 059 /** 060 * Get the underlying data source resolvers. 061 * 062 * @return underlying data source resolvers 063 */ 064 public DataSourceResolver[] getDataSourceResolvers() 065 { 066 // clone the internal array to prevent external modification (see EMAIL-116) 067 final DataSourceResolver[] resolvers = new DataSourceResolver[dataSourceResolvers.length]; 068 System.arraycopy(dataSourceResolvers, 0, resolvers, 0, dataSourceResolvers.length); 069 return resolvers; 070 } 071 072 /** {@inheritDoc} */ 073 @Override 074 public DataSource resolve(final String resourceLocation) throws IOException 075 { 076 final DataSource result = resolve(resourceLocation, true); 077 078 if (isLenient() || result != null) 079 { 080 return result; 081 } 082 throw new IOException("The following resource was not found : " + resourceLocation); 083 084 } 085 086 /** {@inheritDoc} */ 087 @Override 088 public DataSource resolve(final String resourceLocation, final boolean isLenient) throws IOException 089 { 090 for (int i = 0; i < getDataSourceResolvers().length; i++) 091 { 092 final DataSourceResolver dataSourceResolver = getDataSourceResolvers()[i]; 093 final DataSource dataSource = dataSourceResolver.resolve(resourceLocation, isLenient); 094 095 if (dataSource != null) 096 { 097 return dataSource; 098 } 099 } 100 101 if (isLenient) 102 { 103 return null; 104 } 105 throw new IOException("The following resource was not found : " + resourceLocation); 106 } 107}