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2 * Licensed to the Apache Software Foundation (ASF) under one *
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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 *
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10 * http://www.apache.org/licenses/LICENSE-2.0 *
11 * *
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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
21
22 package org.apache.james.util.codec;
23
24 import javax.mail.MessagingException;
25 import javax.mail.internet.MimeUtility;
26 import java.io.BufferedReader;
27 import java.io.ByteArrayInputStream;
28 import java.io.ByteArrayOutputStream;
29 import java.io.IOException;
30 import java.io.InputStreamReader;
31
32
33 /**
34 * Performs simple Base64 encoding and decode suitable for authentication.
35 * Note that this is not a general purpose codec.
36 *
37 * @version This is $Revision: 718010 $
38 */
39
40 public class Base64 {
41
42 /**
43 * Decode base64 encoded String
44 *
45 * @param b64string base64 String
46 * @return reader the BufferedReader which holds the decoded base64 text
47 * @throws MessagingException get thrown when an error was detected while trying to decode the String
48 */
49 public static BufferedReader decode(String b64string) throws MessagingException {
50 return new BufferedReader(new InputStreamReader(MimeUtility.decode(
51 new ByteArrayInputStream(b64string.getBytes()), "base64")));
52 }
53
54 /**
55 * Decode base64 encoded String
56 *
57 * @param b64string base64 Sting
58 * @return returnString the String which holds the docoded base64 text
59 * @throws MessagingException get thrown when an error was detected while trying to decode the String
60 * @throws IOException get thrown when I/O error was detected
61 */
62 public static String decodeAsString(String b64string) throws IOException, MessagingException {
63 if (b64string == null) {
64 return b64string;
65 }
66 String returnString = decode(b64string).readLine();
67 if (returnString == null) {
68 return returnString;
69 }
70 return returnString.trim();
71 }
72
73 /**
74 * Encode String to base64
75 *
76 * @param plaintext the plaintext to encode
77 * @return out the ByteArrayOutputStream holding the encoded given text
78 * @throws IOException get thrown when I/O error was detected
79 * @throws MessagingException get thrown when an error was detected while trying to encode the String
80 */
81 public static ByteArrayOutputStream encode(String plaintext) throws IOException, MessagingException {
82 ByteArrayOutputStream out = new ByteArrayOutputStream();
83 byte[] in = plaintext.getBytes();
84 ByteArrayOutputStream inStream = new ByteArrayOutputStream();
85 inStream.write(in, 0, in.length);
86 // pad
87 if ((in.length % 3 ) == 1){
88 inStream.write(0);
89 inStream.write(0);
90 } else if((in.length % 3 ) == 2){
91 inStream.write(0);
92 }
93 inStream.writeTo( MimeUtility.encode(out, "base64") );
94 return out;
95 }
96
97 /**
98 * Encode String to base64
99 *
100 * @param plaintext the plaintext to decode
101 * @return base64String the encoded String
102 * @throws IOException get thrown when I/O error was detected
103 * @throws MessagingException get thrown when an error was detected while trying to encode the String
104 */
105 public static String encodeAsString(String plaintext) throws IOException, MessagingException {
106 return encode(plaintext).toString();
107 }
108
109
110 }