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 java.io.IOException; 020import java.io.InputStream; 021import java.net.MalformedURLException; 022import java.net.URL; 023 024import javax.activation.DataSource; 025import javax.activation.URLDataSource; 026 027/** 028 * Creates a {@code DataSource} based on an URL. 029 * 030 * @since 1.3 031 */ 032public class DataSourceUrlResolver extends DataSourceBaseResolver { 033 034 /** The base url of the resource when resolving relative paths */ 035 private final URL baseUrl; 036 037 /** 038 * Constructs a new instance. 039 * 040 * @param baseUrl the base URL used for resolving relative resource locations 041 */ 042 public DataSourceUrlResolver(final URL baseUrl) { 043 this.baseUrl = baseUrl; 044 } 045 046 /** 047 * Constructs a new instance. 048 * 049 * @param baseUrl the base URL used for resolving relative resource locations 050 * @param lenient shall we ignore resources not found or complain with an exception 051 */ 052 public DataSourceUrlResolver(final URL baseUrl, final boolean lenient) { 053 super(lenient); 054 this.baseUrl = baseUrl; 055 } 056 057 /** 058 * Create an URL based on a base URL and a resource location suitable for loading the resource. 059 * 060 * @param resourceLocation a resource location 061 * @return the corresponding URL 062 * @throws java.net.MalformedURLException creating the URL failed 063 */ 064 protected URL createUrl(final String resourceLocation) throws MalformedURLException { 065 // if we get an non-existing base url than the resource can 066 // be directly used to create an URL 067 if (baseUrl == null) { 068 return new URL(resourceLocation); 069 } 070 // if we get an non-existing location what we shall do? 071 if (resourceLocation == null || resourceLocation.isEmpty()) { 072 throw new IllegalArgumentException("No resource defined"); 073 } 074 // if we get a stand-alone resource than ignore the base url 075 if (isFileUrl(resourceLocation) || isHttpUrl(resourceLocation)) { 076 return new URL(resourceLocation); 077 } 078 return new URL(getBaseUrl(), resourceLocation.replace("&", "&")); 079 } 080 081 /** 082 * Gets the base URL used for resolving relative resource locations. 083 * 084 * @return the baseUrl 085 */ 086 public URL getBaseUrl() { 087 return baseUrl; 088 } 089 090 /** {@inheritDoc} */ 091 @Override 092 public DataSource resolve(final String resourceLocation) throws IOException { 093 return resolve(resourceLocation, isLenient()); 094 } 095 096 /** {@inheritDoc} */ 097 @Override 098 public DataSource resolve(final String resourceLocation, final boolean isLenient) throws IOException { 099 DataSource result = null; 100 try { 101 if (!isCid(resourceLocation)) { 102 result = new URLDataSource(createUrl(resourceLocation)); 103 // validate we can read. 104 try (InputStream inputStream = result.getInputStream()) { 105 inputStream.read(); 106 } 107 } 108 return result; 109 } catch (final IOException e) { 110 if (isLenient) { 111 return null; 112 } 113 throw e; 114 } 115 } 116}