commons-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From scolebou...@apache.org
Subject cvs commit: jakarta-commons/lang/src/java/org/apache/commons/lang/util IdentifierUtils.java
Date Sun, 29 Dec 2002 21:35:04 GMT
scolebourne    2002/12/29 13:35:04

  Modified:    lang/src/test/org/apache/commons/lang/util
                        UtilTestSuite.java
  Added:       lang/src/test/org/apache/commons/lang/util
                        IdentifierUtilsTest.java
               lang/src/java/org/apache/commons/lang/util
                        IdentifierUtils.java
  Log:
  Add Identifier generators to Lang from Util
  
  Revision  Changes    Path
  1.2       +2 -1      jakarta-commons/lang/src/test/org/apache/commons/lang/util/UtilTestSuite.java
  
  Index: UtilTestSuite.java
  ===================================================================
  RCS file: /home/cvs/jakarta-commons/lang/src/test/org/apache/commons/lang/util/UtilTestSuite.java,v
  retrieving revision 1.1
  retrieving revision 1.2
  diff -u -r1.1 -r1.2
  --- UtilTestSuite.java	18 Dec 2002 02:50:36 -0000	1.1
  +++ UtilTestSuite.java	29 Dec 2002 21:35:03 -0000	1.2
  @@ -86,6 +86,7 @@
           TestSuite suite = new TestSuite();
           suite.setName("Commons-Lang-Util Tests");
           suite.addTest(BitFieldTest.suite());
  +        suite.addTest(IdentifierUtilsTest.suite());
           return suite;
       }
   }
  
  
  
  1.1                  jakarta-commons/lang/src/test/org/apache/commons/lang/util/IdentifierUtilsTest.java
  
  Index: IdentifierUtilsTest.java
  ===================================================================
  /* ====================================================================
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 2002 The Apache Software Foundation.  All rights
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "The Jakarta Project", "Commons", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   */
  package org.apache.commons.lang.util;
  
  import junit.framework.Test;
  import junit.framework.TestSuite;
  
  import org.apache.commons.lang.functor.Factory;
  import org.apache.commons.lang.functor.FactoryException;
  /**
   * Tests the org.apache.commons.lang.util.IdentifierUtils class.
   *
   * @author Stephen Colebourne
   * @version $Id: IdentifierUtilsTest.java,v 1.1 2002/12/29 21:35:03 scolebourne Exp $
   */
  public class IdentifierUtilsTest extends junit.framework.TestCase {
  
      /**
       * Construct
       */
      public IdentifierUtilsTest(String name) {
          super(name);
      }
  
      /**
       * Return class aa a test suite.
       */
      public static Test suite() {
          TestSuite suite = new TestSuite(IdentifierUtilsTest.class);
          suite.setName("IdentifierUtils Tests");
          return suite;
      }
  
      //--------------------------------------------------------------------------
  
      public void testLongIncrementing() {
          Factory f = IdentifierUtils.LONG_IDENTIFIER_FACTORY;
          assertEquals(new Long(0), f.create());
          assertEquals(new Long(1), f.create());
          assertEquals(new Long(2), f.create());
          assertEquals(new Long(3), f.create());
          assertEquals(new Long(4), IdentifierUtils.nextLongIdentifier());
          assertEquals(new Long(5), f.create());
          assertEquals(new Long(6), IdentifierUtils.nextLongIdentifier());
          assertEquals(new Long(7), IdentifierUtils.nextLongIdentifier());
      }
  
      public void testLongIncrementingNoArgs() {
          Factory f = IdentifierUtils.longIdentifierFactory();
          assertEquals(new Long(0), f.create());
          assertEquals(new Long(1), f.create());
          assertTrue(f != IdentifierUtils.LONG_IDENTIFIER_FACTORY);
      }
  
      public void testLongIncrementingInit() {
          Factory f = IdentifierUtils.longIdentifierFactory(true, 100);
          assertEquals(new Long(100), f.create());
          assertEquals(new Long(101), f.create());
      }
  
      public void testLongIncrementingWrap() {
          Factory f = IdentifierUtils.longIdentifierFactory(true, Long.MAX_VALUE);
          assertEquals(new Long(Long.MAX_VALUE), f.create());
          assertEquals(new Long(Long.MIN_VALUE), f.create());
      }
  
      public void testLongIncrementingNoWrap() {
          Factory f = IdentifierUtils.longIdentifierFactory(false, Long.MAX_VALUE);
          try {
              f.create();
              fail();
          } catch (FactoryException ex) {}
      }
  
      //--------------------------------------------------------------------------
  
      public void testStringNumericLong() {
          Factory f = IdentifierUtils.STRING_NUMERIC_IDENTIFIER_FACTORY;
          assertEquals("0", f.create());
          assertEquals("1", f.create());
          assertEquals("2", f.create());
          assertEquals("3", f.create());
          assertEquals("4", IdentifierUtils.nextStringNumericIdentifier());
          assertEquals("5", f.create());
          assertEquals("6", IdentifierUtils.nextStringNumericIdentifier());
          assertEquals("7", IdentifierUtils.nextStringNumericIdentifier());
      }
  
      public void testStringNumericNoArgs() {
          Factory f = IdentifierUtils.stringNumericIdentifierFactory();
          assertEquals("0", f.create());
          assertEquals("1", f.create());
          assertTrue(f != IdentifierUtils.STRING_NUMERIC_IDENTIFIER_FACTORY);
      }
  
      public void testStringNumericInit() {
          Factory f = IdentifierUtils.stringNumericIdentifierFactory(true, 100);
          assertEquals("100", f.create());
          assertEquals("101", f.create());
      }
  
      public void testStringNumericWrap() {
          Factory f = IdentifierUtils.stringNumericIdentifierFactory(true, Long.MAX_VALUE);
          assertEquals(Long.toString(Long.MAX_VALUE), f.create());
          assertEquals(Long.toString(Long.MIN_VALUE), f.create());
      }
  
      public void testStringNumericNoWrap() {
          Factory f = IdentifierUtils.stringNumericIdentifierFactory(false, Long.MAX_VALUE);
          try {
              f.create();
              fail();
          } catch (FactoryException ex) { }
      }
  
      //--------------------------------------------------------------------------
  
      public void testStringAlphanumeric() {
          Factory f = IdentifierUtils.STRING_ALPHANUMERIC_IDENTIFIER_FACTORY;
          assertEquals("000000000000001", f.create());
          assertEquals("000000000000002", f.create());
          assertEquals("000000000000003", f.create());
          assertEquals("000000000000004", f.create());
          assertEquals("000000000000005", f.create());
          assertEquals("000000000000006", f.create());
          assertEquals("000000000000007", f.create());
          assertEquals("000000000000008", f.create());
          assertEquals("000000000000009", f.create());
          assertEquals("00000000000000a", f.create());
          assertEquals("00000000000000b", f.create());
          assertEquals("00000000000000c", f.create());
          assertEquals("00000000000000d", IdentifierUtils.nextStringAlphanumericIdentifier());
          assertEquals("00000000000000e", f.create());
          assertEquals("00000000000000f", f.create());
          assertEquals("00000000000000g", f.create());
          assertEquals("00000000000000h", f.create());
          assertEquals("00000000000000i", f.create());
          assertEquals("00000000000000j", f.create());
          assertEquals("00000000000000k", f.create());
          assertEquals("00000000000000l", f.create());
          assertEquals("00000000000000m", f.create());
          assertEquals("00000000000000n", f.create());
          assertEquals("00000000000000o", f.create());
          assertEquals("00000000000000p", f.create());
          assertEquals("00000000000000q", f.create());
          assertEquals("00000000000000r", f.create());
          assertEquals("00000000000000s", f.create());
          assertEquals("00000000000000t", f.create());
          assertEquals("00000000000000u", f.create());
          assertEquals("00000000000000v", f.create());
          assertEquals("00000000000000w", f.create());
          assertEquals("00000000000000x", f.create());
          assertEquals("00000000000000y", f.create());
          assertEquals("00000000000000z", f.create());
          assertEquals("000000000000010", f.create());
          assertEquals("000000000000011", f.create());
          assertEquals("000000000000012", f.create());
          assertEquals("000000000000013", f.create());
      }
  
      public void testLongAlphanumericNoArgs() {
          Factory f = IdentifierUtils.stringAlphanumericIdentifierFactory();
          assertEquals("000000000000001", f.create());
          assertEquals("000000000000002", f.create());
          assertTrue(f != IdentifierUtils.STRING_ALPHANUMERIC_IDENTIFIER_FACTORY);
      }
  
      public void testStringAlphanumericWrap() {
          Factory f = IdentifierUtils.stringAlphanumericIdentifierFactory(true, 1);
          assertEquals("1", f.create());
          assertEquals("2", f.create());
          assertEquals("3", f.create());
          assertEquals("4", f.create());
          assertEquals("5", f.create());
          assertEquals("6", f.create());
          assertEquals("7", f.create());
          assertEquals("8", f.create());
          assertEquals("9", f.create());
          assertEquals("a", f.create());
          assertEquals("b", f.create());
          assertEquals("c", f.create());
          assertEquals("d", f.create());
          assertEquals("e", f.create());
          assertEquals("f", f.create());
          assertEquals("g", f.create());
          assertEquals("h", f.create());
          assertEquals("i", f.create());
          assertEquals("j", f.create());
          assertEquals("k", f.create());
          assertEquals("l", f.create());
          assertEquals("m", f.create());
          assertEquals("n", f.create());
          assertEquals("o", f.create());
          assertEquals("p", f.create());
          assertEquals("q", f.create());
          assertEquals("r", f.create());
          assertEquals("s", f.create());
          assertEquals("t", f.create());
          assertEquals("u", f.create());
          assertEquals("v", f.create());
          assertEquals("w", f.create());
          assertEquals("x", f.create());
          assertEquals("y", f.create());
          assertEquals("z", f.create());
          assertEquals("0", f.create());
      }
  
      public void testStringAlphanumericNoWrap() {
          Factory f = IdentifierUtils.stringAlphanumericIdentifierFactory(false, 1);
          assertEquals("1", f.create());
          assertEquals("2", f.create());
          assertEquals("3", f.create());
          assertEquals("4", f.create());
          assertEquals("5", f.create());
          assertEquals("6", f.create());
          assertEquals("7", f.create());
          assertEquals("8", f.create());
          assertEquals("9", f.create());
          assertEquals("a", f.create());
          assertEquals("b", f.create());
          assertEquals("c", f.create());
          assertEquals("d", f.create());
          assertEquals("e", f.create());
          assertEquals("f", f.create());
          assertEquals("g", f.create());
          assertEquals("h", f.create());
          assertEquals("i", f.create());
          assertEquals("j", f.create());
          assertEquals("k", f.create());
          assertEquals("l", f.create());
          assertEquals("m", f.create());
          assertEquals("n", f.create());
          assertEquals("o", f.create());
          assertEquals("p", f.create());
          assertEquals("q", f.create());
          assertEquals("r", f.create());
          assertEquals("s", f.create());
          assertEquals("t", f.create());
          assertEquals("u", f.create());
          assertEquals("v", f.create());
          assertEquals("w", f.create());
          assertEquals("x", f.create());
          assertEquals("y", f.create());
          assertEquals("z", f.create());
          try {
              f.create();
              fail();
          } catch (FactoryException ex) {}
      }
  
      //--------------------------------------------------------------------------
  
      public void testStringSession() {
          Factory f = IdentifierUtils.STRING_SESSION_IDENTIFIER_FACTORY;
          assertTrue(f != IdentifierUtils.stringSessionIdentifierFactory());
          
          String a = (String) f.create();
          String b = (String) IdentifierUtils.nextStringSessionIdentifier();
          assertTrue(a.length() >= 10);
          assertTrue(b.length() >= 10);
          // could fail, but unlikely
          assertTrue(a.substring(6, 9) != b.substring(6, 9));
          assertEquals("0", a.substring(9));
          assertEquals("1", b.substring(9));
      }
  
      //--------------------------------------------------------------------------
  
  }
  
  
  
  1.1                  jakarta-commons/lang/src/java/org/apache/commons/lang/util/IdentifierUtils.java
  
  Index: IdentifierUtils.java
  ===================================================================
  /* ====================================================================
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 2002 The Apache Software Foundation.  All rights
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "The Jakarta Project", "Commons", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   */
  package org.apache.commons.lang.util;
  
  import java.io.Serializable;
  import java.util.Random;
  
  import org.apache.commons.lang.functor.Factory;
  import org.apache.commons.lang.functor.FactoryException;
  /**
   * <p><code>IdentifierUtils</code> provides a number of different identifier
   * reference implementations.</p>
   * 
   * <p>All the identifer factories are serializable and synchronized. The
   * factories all implement the <i>functor</i> 
   * {@link org.apache.commons.lang.functor.Factory Factory} interface</p>
   *
   * @author Stephen Colebourne
   * @version $Id: IdentifierUtils.java,v 1.1 2002/12/29 21:35:04 scolebourne Exp $
   */
  public class IdentifierUtils {
  
      /**
       * <p>Singleton instance of the
       * <code>LongIdentifierFactory</code>.</p>
       * 
       * <p>The singleton instance will wrap, so in a long-lived server, the id
       * may be duplicated.</p>
       * 
       * <p>The objects returned are:</p>
       * <ul>
       * <li>new Long(0L)
       * <li>new Long(1L)
       * <li>new Long(2L)
       * <li>...
       * </ul>
  	 */
      public static final Factory LONG_IDENTIFIER_FACTORY = new LongIdentifierFactory(true,
0L);
      /**
       * <p>Singleton instance of the <code>StringNumericIdentifierFactory</code>.
       * </p>
       * 
       * <p>The singleton instance will wrap, so in a long-lived server, the id
       * may be duplicated.</p>
       * 
       * <p>The objects returned are:</p>
       * <ul>
       * <li>"0"
       * <li>"1"
       * <li>"2"
       * <li>...
       * </ul>
       */
      public static final Factory STRING_NUMERIC_IDENTIFIER_FACTORY = new StringNumericIdentifierFactory(true,
0L);
      /**
       * <p>Singleton instance of the
       * <code>StringAlphanumericIdentifierFactory</code>.</p>
       * 
       * <p>The singleton instance will wrap, so in a long-lived server, the id
       * may be duplicated. However, the length is 15 in base-36, so thats a
       * lot of identifiers.</p>
       * 
       * <p>The objects returned are:</p>
       * <ul>
       * <li>"000000000000001"
       * <li>"000000000000002"
       * <li>"000000000000003"
       * <li>...
       * <li>"00000000000000y"
       * <li>"00000000000000z"
       * <li>"000000000000010"
       * <li>"000000000000011"
       * <li>...
       * <li>"00000000000001z"
       * <li>"000000000000020"
       * <li>...
       * </ul>
       */
      public static final Factory STRING_ALPHANUMERIC_IDENTIFIER_FACTORY = new StringAlphanumericIdentifierFactory(true,
15);
      /**
       * <p>Singleton instance of the
       * <code>StringSessionIdentifierFactory</code>.</p>
       * 
       * <p>The singleton instance may produce duplicates in a long-lived server,
       * but its unlikely.</p>
       * 
       * <p>The objects returned are 10 or more base-36 digits.</p>
       */
      public static final Factory STRING_SESSION_IDENTIFIER_FACTORY = new StringSessionIdentifierFactory();
  
      //---------------------------------------------------------------------------------
      
      /**
       * <p><code>IdentifierUtils</code> instances should NOT be constructed
in
       * standard programming.</p>
       *
       * <p>This constructor is public to permit tools that require a JavaBean instance
       * to operate.</p>
       */
      public IdentifierUtils() {
          super();
      }
  
      //---------------------------------------------------------------------------------
      
      /**
       * <p>Gets the next identifier using the singleton instance of the
       * Long factory.
       * </p>
       * 
       * <p>The singleton instance will wrap, so in a long-lived server, the id
       * may be duplicated.</p>
       * 
       * @return a new identifier
       */
      public static Long nextLongIdentifier() {
          return (Long) LONG_IDENTIFIER_FACTORY.create();
      }
  
      /**
       * <p>Gets a new identifier factory that returns a series of Long objects
       * increasing in size.</p>
       * 
       * <p>The factory will wrap when the maximum <code>long</code> is
       * reached and return negative numbers. It will start from zero.</p>
       * 
       * @return a new identifier factory
       */
      public static Factory longIdentifierFactory() {
          return new LongIdentifierFactory(true, 0L);
      }
  
      /**
       * <p>Gets a new identifier factory that returns a series of Long objects
       * increasing in size.</p>
       * 
       * @param wrap  should the factory wrap when it reaches the maximum 
       *  long value (or throw an exception)
       * @param initialValue  the initial long value to start at
       * @return a new identifier factory
       */
      public static Factory longIdentifierFactory(boolean wrap, long initialValue) {
          return new LongIdentifierFactory(wrap, initialValue);
      }
      
      //---------------------------------------------------------------------------------
      
      /**
       * <p>Gets the next identifier using the singleton instance of the
       * String Numeric factory.
       * </p>
       * 
       * <p>The singleton instance will wrap, so in a long-lived server, the id
       * may be duplicated.</p>
       * 
       * @return a new identifier
       */
      public static String nextStringNumericIdentifier() {
          return (String) STRING_NUMERIC_IDENTIFIER_FACTORY.create();
      }
  
      /**
       * <p>Gets a new identifier factory that returns a series of String objects
       * representing numbers increasing in size.</p>
       * 
       * <p>The factory will wrap when the maximum <code>long</code> is
       * reached and return negative numbers. It will start from zero.</p>
       * 
       * @return a new identifier factory
       */
      public static Factory stringNumericIdentifierFactory() {
          return new StringNumericIdentifierFactory(true, 0L);
      }
  
      /**
       * <p>Gets a new identifier factory that returns a series of String objects
       * representing numbers increasing in size.</p>
       * 
       * @param wrap  should the factory wrap when it reaches the maximum 
       *  long value (or throw an exception)
       * @param initialValue  the initial long value to start at
       * @return a new identifier factory
       */
      public static Factory stringNumericIdentifierFactory(boolean wrap, long initialValue)
{
          return new StringNumericIdentifierFactory(wrap, initialValue);
      }
      
      //---------------------------------------------------------------------------------
      
      /**
       * <p>Gets the next identifier using the singleton instance of the
       * String Alphanumeric factory.
       * </p>
       * 
       * <p>The singleton instance will wrap, so in a long-lived server, the id
       * may be duplicated.</p>
       * 
       * @return a new identifier
       */
      public static String nextStringAlphanumericIdentifier() {
          return (String) STRING_ALPHANUMERIC_IDENTIFIER_FACTORY.create();
      }
  
      /**
       * <p>Gets a new identifier factory that returns a series of String objects
       * representing numbers increasing in size in base-36.</p>
       * 
       * <p>The factory will wrap when the maximum size (15) is reached.</p>
       * 
       * @return a new identifier factory
       */
      public static Factory stringAlphanumericIdentifierFactory() {
          return new StringAlphanumericIdentifierFactory(true, 15);
      }
  
      /**
       * <p>Gets a new identifier factory that returns a series of String objects
       * representing numbers increasing in size in base-36.</p>
       * 
       * @param wrap  should the factory wrap when it reaches the maximum 
       *  size (or throw an exception)
       * @param size  the number of characters the id should fill
       * @return a new identifier factory
       */
      public static Factory stringAlphanumericIdentifierFactory(boolean wrap, int size) {
          return new StringAlphanumericIdentifierFactory(wrap, size);
      }
      
      //---------------------------------------------------------------------------------
      
      /**
       * <p>Gets the next identifier using the singleton instance of the
       * String Session factory.
       * </p>
       * 
       * <p>The singleton instance is not guaranteed to be unique (although its
       * pretty unlikely), so in a long- lived server, the id may be duplicated.
       * </p>
       * 
       * @return a new identifier
       */
      public static String nextStringSessionIdentifier() {
          return (String) STRING_SESSION_IDENTIFIER_FACTORY.create();
      }
  
      /**
       * <p>Gets a new identifier factory that returns a series of String objects
       * that appear to be random and are suitable for use as session identifiers.
       * </p>
       * 
       * <p>The generation routine is based on a random number and a counter
       * within a 2 second time interval.</p>
       * 
       * @return a new identifier factory
       */
      public static Factory stringSessionIdentifierFactory() {
          return new StringSessionIdentifierFactory();
      }
  
      //---------------------------------------------------------------------------------
  
      /**
       * <code>LongIdentifierFactory</code> is an Identifier Factory
       * that generates an incrementing number as a Long object.
       *
       * @author Stephen Colebourne
       */
      private static class LongIdentifierFactory implements Factory, Serializable {
      
          /** Should the counter wrap. */
          private final boolean wrap;
          /** The counter. */
          private long count = 0;
      
          /**
           * Constructor.
           * 
           * @param wrap  should the factory wrap when it reaches the maximum 
           *  long value (or throw an exception)
           * @param initialValue  the initial long value to start at
           */
          private LongIdentifierFactory(boolean wrap, long initialValue) {
              super();
              this.wrap = wrap;
              this.count = initialValue;
          }
  
          /**
           * Create a new identifier.
           * 
           * @return a new identifier as a Long
           */
          public Object create() {
              long value = 0;
              if (wrap) {
                  synchronized (this) {
                      value = count++;
                  }
              } else {
                  synchronized (this) {
                      if (count == Long.MAX_VALUE) {
                          throw new FactoryException("The maximum number of identifiers has
been reached");
                      }
                      value = count++;
                  }
              }
              return new Long(value);
          }
      }
  
      //---------------------------------------------------------------------------------
  
      /**
       * <code>StringNumericIdentifierFactory</code> is an Identifier Factory
       * that generates an incrementing number as a String object.
       *
       * @author Stephen Colebourne
       */
      private static class StringNumericIdentifierFactory implements Factory, Serializable
{
      
          /** Should the counter wrap. */
          private final boolean wrap;
          /** The counter. */
          private long count = 0;
          
          /**
           * Constructor.
           * 
           * @param wrap  should the factory wrap when it reaches the maximum 
           *  long value (or throw an exception)
           * @param initialValue  the initial long value to start at
           */
          private StringNumericIdentifierFactory(boolean wrap, long initialValue) {
              super();
              this.wrap = wrap;
              this.count = initialValue;
          }
  
          /**
           * Create a new identifier.
           * 
           * @return a new identifier as a String
           */
          public Object create() {
              long value = 0;
              if (wrap) {
                  synchronized (this) {
                      value = count++;
                  }
              } else {
                  synchronized (this) {
                      if (count == Long.MAX_VALUE) {
                          throw new FactoryException("The maximum number of identifiers has
been reached");
                      }
                      value = count++;
                  }
              }
              return Long.toString(value);
          }
  
      }
      
      //---------------------------------------------------------------------------------
  
      /**
       * <code>StringAlphanumericIdentifierFactory</code> is an Identifier Factory
       * that generates an incrementing incrementing number in base 36 as a String
       * object.
       *
       * @author Stephen Colebourne
       */
      private static class StringAlphanumericIdentifierFactory implements Factory, Serializable
{
      
          /** Should the counter wrap. */
          private final boolean wrap;
          /** The counter. */
          private char[] count = null;
          
          /**
           * Constructor.
           * 
           * @param wrap  should the factory wrap when it reaches the maximum 
           *  long value (or throw an exception)
           * @param size  the size of the identifier
           */
          private StringAlphanumericIdentifierFactory(boolean wrap, int size) {
              super();
              this.wrap = wrap;
              if (size < 1) {
                  throw new IllegalArgumentException("The size must be at least one");
              }
              this.count = new char[size];
              for (int i = 0; i < size; i++) {
                  count[i] = '0';  // zero
              }
          }
  
          /**
           * Create a new identifier.
           * 
           * @return a new identifier as a String
           */
          public synchronized Object create() {
              for (int i = count.length - 1; i >= 0; i--) {
                  switch (count[i]) {
                      case 122:  // z
                      count[i] = '0';
                      if (i == 0 && wrap == false) {
                          throw new FactoryException("The maximum number of identifiers has
been reached");
                      }
                      break;
                      
                      case 57:  // 9
                      count[i] = 'a';
                      i = -1;
                      break;
                      
                      default:
                      count[i]++;
                      i = -1;
                      break;
                  }
              }
              return new String(count);
          }
  
      }
      
      //---------------------------------------------------------------------------------
      
      /**
       * <p><code>StringSessionIdentifierFactory</code> is an Identifier
       * Factory that generates an alphanumeric 10+ character identifier. The
       * exact length depends on the number of ids requested per time period.</p>
       * 
       * <p>Originally designed for JServ sessions. Uses synchronized count and
       * time to ensure uniqueness. Not guaranteed unique across JVMs, but
       * fairly safe none the less.</p>
       *
       * @author Jon S. Stevens
       * @author Neeme Praks
       * @author Stephen Colebourne
       */
      private static class StringSessionIdentifierFactory implements Factory, Serializable
{
  
          /**
           * We want to have a random string with a length of 6 characters.
           * Since we encode it base-36, we modulo the random number with
           * this value.
           */
          private static final long MAX_RANDOM_LEN = 2176782336L; // 36 ** 6
          /**
           * The identifier must be unique within the typical lifespan of a
           * session; the value can roll over after that.  3 characters:
           * (this means a roll over after over a day, which is much larger
           * than a typical lifespan).
           */
          private static final long MAX_TIME_SECTION_LEN = 46656L; // 36 ** 3
          /**
           * Milliseconds between different tics.  The 3-character time
           * string has a new value every 2 seconds.
           */
          private static final long TIC_DIFFERENCE = 2000;
          
          /** The incrementing counter. */
          private int counter = 0;
          /** The last time. */
          private long lastTimeValue = 0;
          /** The randmonizer. */
          private Random randomizer = new Random();
  
          /**
           * Constructor.
           */
          private StringSessionIdentifierFactory() {
              super();
          }
  
          /**
           * Create a new identifier. Only guaranteed unique within
           * this JVM, but fairly safe for cross JVM usage as well.
           * 
           * <p>Format of identifier is
           * [6 chars random][3 chars time][1+ chars count]</p>
           * 
           * @return a new identifier as a Long
           */
          public Object create() {
              // Random value
              //--------------
              long currentRandom = randomizer.nextLong();
              if (currentRandom < 0) {
                  currentRandom = -currentRandom;
              }
              // force value into 6 char range, and add to pad with zeros
              // this gives a length of 7, when converted to base 36, and
              // the first character (always 1 from the add) is dropped
              currentRandom %= MAX_RANDOM_LEN;
              currentRandom += MAX_RANDOM_LEN;
  
              long currentTimeValue = 0;
              int currentCount = 0;
          
              synchronized (this) {
                  // Time
                  //--------------
                  currentTimeValue = (System.currentTimeMillis() / TIC_DIFFERENCE);
      
                  // force value into 3 char range, and add to pad with zeros
                  // this gives a length of 4, when converted to base 36, and
                  // the first character (always 1 from the add) is dropped
                  currentTimeValue %= MAX_TIME_SECTION_LEN;
                  currentTimeValue += MAX_TIME_SECTION_LEN;
      
                  // Count
                  //--------------
                  // Make the string unique by appending the count since last
                  // time flip.
      
                  // Count sessions only within tics (so the 'real' counter
                  // isn't exposed to the public).
                  if (lastTimeValue != currentTimeValue) {
                      lastTimeValue = currentTimeValue;
                      counter = 0;
                  }
                  currentCount = counter++;
              }
  
              // build string        
              //--------------
              StringBuffer id = new StringBuffer(15);
              id.append(Long.toString(currentRandom, 36).substring(1));  // 6 chars
              id.append(Long.toString(currentTimeValue, 36).substring(1));  // 3 chars
              id.append(Long.toString(currentCount, 36));  // 1+ chars
              return id.toString();
          }
  
      }
      
  }
  
  
  

--
To unsubscribe, e-mail:   <mailto:commons-dev-unsubscribe@jakarta.apache.org>
For additional commands, e-mail: <mailto:commons-dev-help@jakarta.apache.org>


Mime
View raw message