##### Coverage Report - org.apache.turbine.util.GenerateUniqueId

Classes in this File | Line Coverage | Branch Coverage | Complexity
GenerateUniqueId |
0% | 0/27
0% | 0/8
| 2.6666666666666665;2,667

1 |  |
     package org.apache.turbine.util;
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     /*
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      * Licensed to the Apache Software Foundation (ASF) under one
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      * or more contributor license agreements.  See the NOTICE file
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      * distributed with this work for additional information
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      * regarding copyright ownership.  The ASF licenses this file
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      * to you under the Apache License, Version 2.0 (the
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      * "License"); you may not use this file except in compliance
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      * with the License.  You may obtain a copy of the License at
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      *
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      *   http://www.apache.org/licenses/LICENSE-2.0
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      *
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      * Unless required by applicable law or agreed to in writing,
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      * software distributed under the License is distributed on an
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      * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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      * KIND, either express or implied.  See the License for the
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      * specific language governing permissions and limitations
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      * under the License.
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      */
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     import java.util.Random;
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     /**
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      * This class generates a unique 10+ character id.  This is good for
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      * authenticating users or tracking users around.
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      *
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      * <p>This code was borrowed from Apache
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      * JServ.JServServletManager.java.  It is what Apache JServ uses to
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      * generate session ids for users.  Unfortunately, it was not included
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      * in Apache JServ as a class, so I had to create one here in order to
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      * use it.
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      *
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      * @author <a href="mailto:jon@clearink.com">Jon S. Stevens</a>
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      * @author <a href="mailto:neeme@one.lv">Neeme Praks</a>
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      * @version $Id: GenerateUniqueId.java 615328 2008-01-25 20:25:05Z tv $
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      */
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     public class GenerateUniqueId
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     {
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         /*
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          * Create a suitable string for session identification.  Use
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          * synchronized count and time to ensure uniqueness.  Use random
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          * string to ensure the timestamp cannot be guessed by programmed
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          * attack.
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          *
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          * Format of id is <6 chars random><3 chars time><1+ char count>
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          */
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         static private int session_count = 0;
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         static private long lastTimeVal = 0;
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         static private Random randomSource = new java.util.Random();
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         // MAX_RADIX is 36
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         /*
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          * We want to have a random string with a length of 6 characters.
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          * Since we encode it BASE 36, we've to modulo it with the
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          * following value:
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          */
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         public final static long maxRandomLen = 2176782336L; // 36 ** 6
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         /*
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          * The session identifier must be unique within the typical
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          * lifespan of a Session; the value can roll over after that.  3
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          * characters: (this means a roll over after over a day, which is
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          * much larger than a typical lifespan)
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          */
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         public final static long maxSessionLifespanTics = 46656; // 36 ** 3
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         /*
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          * Millisecons between different tics.  So this means that the
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          * 3-character time string has a new value every 2 seconds:
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          */
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         public final static long ticDifference = 2000;
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         /**
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          * Get the unique id.
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          *
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          * <p>NOTE: This must work together with
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          * get_jserv_session_balance() in jserv_balance.c
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          *
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          * @return A String with the new unique id.
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          */
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         static synchronized public String getIdentifier()
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         {
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             StringBuffer sessionId = new StringBuffer();
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             // Random value.
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             long n = randomSource.nextLong();
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             if (n < 0) n = -n;
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             n %= maxRandomLen;
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             // Add maxLen to pad the leading characters with '0'; remove
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             // first digit with substring.
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             n += maxRandomLen;
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             sessionId.append(Long.toString(n, Character.MAX_RADIX)
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                     .substring(1));
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             long timeVal = (System.currentTimeMillis() / ticDifference);
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             // Cut.
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             timeVal %= maxSessionLifespanTics;
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             // Padding, see above.
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             timeVal += maxSessionLifespanTics;
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             sessionId.append(Long.toString(timeVal, Character.MAX_RADIX)
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                     .substring(1));
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             /*
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              * Make the string unique: append the session count since last
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              * time flip.
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              */
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             // Count sessions only within tics.  So the 'real' session
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             // count isn't exposed to the public.
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             if (lastTimeVal != timeVal)
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             {
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                 lastTimeVal = timeVal;
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                 session_count = 0;
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             }
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             sessionId.append(Long.toString(++session_count,
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                     Character.MAX_RADIX));
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126 | 0 |
             return sessionId.toString();
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         }
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         /**
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          * Get the unique id.
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          *
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          * @param jsIdent A String.
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          * @return A String with the new unique id.
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          */
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         synchronized public String getIdentifier(String jsIdent)
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         {
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             if (jsIdent != null && jsIdent.length() > 0)
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             {
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                 return getIdentifier() + "." + jsIdent;
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             }
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             return getIdentifier();
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         }
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         /**
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          * Simple test of the functionality.
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          *
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          * @param args A String[] with the command line arguments.
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          */
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         public static void main(String[] args)
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         {
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             System.out.println(GenerateUniqueId.getIdentifier());
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             System.out.println(GenerateUniqueId.getIdentifier());
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             System.out.println(GenerateUniqueId.getIdentifier());
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             System.out.println(GenerateUniqueId.getIdentifier());
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         }
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     }