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1   /*
2    * Copyright 2007-2008 the original author or authors.
3    * 
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  package org.gwe.p2elv2.functions;
18  
19  import java.security.MessageDigest;
20  import java.security.NoSuchAlgorithmException;
21  import java.util.List;
22  
23  import org.gwe.p2elv2.PFunction;
24  import org.gwe.p2elv2.PStatementContext;
25  import org.gwe.p2elv2.PVarValueSpace;
26  
27  /**
28   * @author Marco Ruiz
29   * @since Aug 4, 2008
30   */
31  public class PFMD5Hex extends PFunction {
32  	
33      public static final String FUNCTION_NAME = "md5Hex";
34  
35  	public PFMD5Hex() { super(FUNCTION_NAME); }
36      
37      public PVarValueSpace calculateValues(List<String> params, PStatementContext ctx) {
38      	PVarValueSpace result = new PVarValueSpace();
39  		for (String param : params) result.add(createHashHex(param));
40  		return result;
41      }
42  
43  	private String createHashHex(String param) {
44  	    byte[] hash = createMD5Hash(param);
45  	    return bytesToHex(hash);
46      }
47      
48      private byte[] createMD5Hash(String key) {
49      	MessageDigest longHash;
50          try {
51              longHash = MessageDigest.getInstance("MD5");
52      		longHash.update(key.getBytes());
53      		return longHash.digest();
54          } catch (NoSuchAlgorithmException e) {
55          	// TODO: Handle!!!
56  //        	log.fatal("Security not available because basic infrastructure to provide it is not available.", e);
57          }
58          return null;
59      }
60      
61  	public String bytesToHex(byte[] b) {
62  		char hexDigit[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
63  		StringBuffer buf = new StringBuffer();
64  		for (int j = 0; j < b.length; j++) {
65  			buf.append(hexDigit[(b[j] >> 4) & 0x0f]);
66  			buf.append(hexDigit[b[j] & 0x0f]);
67  		}
68  		return buf.toString();
69  	}
70  	
71  	public static void main(String[] args) {
72  		PFMD5Hex function = new PFMD5Hex();
73  		System.out.println(function.createHashHex("user-1"));
74  		System.out.println(function.createHashHex("user-2"));
75  		System.out.println(function.createHashHex("http://host/path/file-1"));
76  		System.out.println(function.createHashHex("http://host/path/file-2"));
77  	}
78  }
79