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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.mail2.jakarta.resolver;
18  
19  import java.io.IOException;
20  import java.io.InputStream;
21  import java.net.URL;
22  
23  import jakarta.activation.DataSource;
24  import jakarta.activation.FileTypeMap;
25  import jakarta.mail.util.ByteArrayDataSource;
26  
27  /**
28   * Creates a {@code DataSource} based on an class path.
29   *
30   * @since 1.3
31   */
32  public class DataSourceClassPathResolver extends DataSourceBaseResolver {
33      /** The base string of the resource relative to the classpath when resolving relative paths */
34      private final String classPathBase;
35  
36      /**
37       * Constructs a new instance.
38       */
39      public DataSourceClassPathResolver() {
40          this("/");
41      }
42  
43      /**
44       * Constructs a new instance.
45       *
46       * @param classPathBase a base class path
47       */
48      public DataSourceClassPathResolver(final String classPathBase) {
49          this(classPathBase, false);
50      }
51  
52      /**
53       * Constructs a new instance.
54       *
55       * @param classPathBase a base class path
56       * @param lenient       shall we ignore resources not found or throw an exception?
57       */
58      public DataSourceClassPathResolver(final String classPathBase, final boolean lenient) {
59          super(lenient);
60          this.classPathBase = classPathBase.endsWith("/") ? classPathBase : classPathBase + "/";
61      }
62  
63      /**
64       * Gets the class path base.
65       *
66       * @return the classPathBase
67       */
68      public String getClassPathBase() {
69          return classPathBase;
70      }
71  
72      /**
73       * Returns the resource name for a given resource location.
74       *
75       * @param resourceLocation the resource location
76       * @return {@link #getClassPathBase()} + {@code resourceLocation}
77       * @see #getClassPathBase()
78       */
79      private String getResourceName(final String resourceLocation) {
80          return (getClassPathBase() + resourceLocation).replace("//", "/");
81      }
82  
83      /** {@inheritDoc} */
84      @Override
85      public DataSource resolve(final String resourceLocation) throws IOException {
86          return resolve(resourceLocation, isLenient());
87      }
88  
89      /** {@inheritDoc} */
90      @Override
91      public DataSource resolve(final String resourceLocation, final boolean isLenient) throws IOException {
92          try {
93              if (!isCid(resourceLocation) && !isHttpUrl(resourceLocation)) {
94                  final String mimeType = FileTypeMap.getDefaultFileTypeMap().getContentType(resourceLocation);
95                  final String resourceName = getResourceName(resourceLocation);
96                  try (InputStream inputStream = DataSourceClassPathResolver.class.getResourceAsStream(resourceName)) {
97                      if (inputStream == null) {
98                          if (isLenient) {
99                              return null;
100                         }
101                         throw new IOException("The following class path resource was not found : " + resourceLocation);
102                     }
103                     final ByteArrayDataSource ds = new ByteArrayDataSource(inputStream, mimeType);
104                     // EMAIL-125: set the name of the DataSource to the normalized resource URL
105                     // similar to other DataSource implementations, e.g. FileDataSource, URLDataSource
106                     final URL resource = DataSourceClassPathResolver.class.getResource(resourceName);
107                     if (resource != null) {
108                         ds.setName(resource.toString());
109                     } else if (isLenient) {
110                         return null;
111                     } else {
112                         throw new IOException("The following class path resource was not found : " + resourceName);
113                     }
114                     return ds;
115                 }
116             }
117             return null;
118         } catch (final IOException e) {
119             if (isLenient) {
120                 return null;
121             }
122             throw e;
123         }
124     }
125 }