1 /*****************************************************************
2 * Licensed to the Apache Software Foundation (ASF) under one *
3 * or more contributor license agreements. See the NOTICE file *
4 * distributed with this work for additional information *
5 * regarding copyright ownership. The ASF licenses this file *
6 * to you under the Apache License, Version 2.0 (the *
7 * "License"); you may not use this file except in compliance *
8 * with the License. You may obtain a copy of the License at *
9 * *
10 * http://www.apache.org/licenses/LICENSE-2.0 *
11 * *
12 * Unless required by applicable law or agreed to in writing, *
13 * software distributed under the License is distributed on an *
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
15 * KIND, either express or implied. See the License for the *
16 * specific language governing permissions and limitations *
17 * under the License. *
18 ****************************************************************/
19
20 package org.apache.james.core;
21
22 import java.io.IOException;
23 import java.io.InputStream;
24
25 /***
26 * This defines a reusable datasource that can supply an input stream with
27 * MimeMessage data. This allows a MimeMessageWrapper or other classes to
28 * grab the underlying data.
29 *
30 * @see MimeMessageWrapper
31 */
32 public abstract class MimeMessageSource {
33 /***
34 * Returns a unique String ID that represents the location from where
35 * this file is loaded. This will be used to identify where the data
36 * is, primarily to avoid situations where this data would get overwritten.
37 *
38 * @return the String ID
39 */
40 public abstract String getSourceId();
41
42 /***
43 * Get an input stream to retrieve the data stored in the datasource
44 *
45 * @return a <code>InputStream</code> containing the data
46 *
47 * @throws IOException if an error occurs while generating the
48 * InputStream
49 */
50 public abstract InputStream getInputStream() throws IOException;
51
52 /***
53 * Return the size of all the data.
54 * Default implementation... others can override to do this much faster
55 *
56 * @return the size of the data represented by this source
57 * @throws IOException if an error is encountered while computing the message size
58 */
59 public long getMessageSize() throws IOException {
60 int size = 0;
61 InputStream in = null;
62 try {
63 in = getInputStream();
64 int read = 0;
65 byte[] data = new byte[1024];
66 while ((read = in.read(data)) > 0) {
67 size += read;
68 }
69 } finally {
70 try {
71 if (in != null) {
72 in.close();
73 }
74 } catch (IOException ioe) {
75
76
77 }
78 }
79 return size;
80 }
81
82 }