Add in class for dewey decimal representation

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@272500 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/taskdefs/optional/extension/DeweyDecimal.java

@@ -0,0 +1,275 @@
+/*
+ * 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", "Ant", 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 Group.
+ *
+ * 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.tools.ant.taskdefs.optional.extension;
+
+import java.util.StringTokenizer;
+
+/**
+ * Utility class to contain version numbers in "Dewey Decimal"
+ * syntax.  Numbers in the "Dewey Decimal" syntax consist of positive
+ * decimal integers separated by periods ".".  For example, "2.0" or
+ * "1.2.3.4.5.6.7".  This allows an extensible number to be used to
+ * represent major, minor, micro, etc versions.  The version number
+ * must begin with a number.
+ *
+ * @author <a href="mailto:peter@apache.org">Peter Donald</a>
+ * @version $Revision$ $Date$
+ */
+public final class DeweyDecimal
+{
+    ///Array of components that make up DeweyDecimal
+    private int[] m_components;
+
+    /**
+     * Construct a DeweyDecimal from an array of integer components.
+     *
+     * @param components an array of integer components.
+     */
+    public DeweyDecimal( final int[] components )
+    {
+        m_components = new int[ components.length ];
+
+        for( int i = 0; i < m_components.length; i++ )
+        {
+            m_components[ i ] = components[ i ];
+        }
+    }
+
+    /**
+     * Construct a DeweyDecimal from string in DeweyDecimal format.
+     *
+     * @param string the string in dewey decimal format
+     * @exception NumberFormatException if string is malformed
+     */
+    public DeweyDecimal( final String string )
+        throws NumberFormatException
+    {
+        final StringTokenizer tokenizer = new StringTokenizer( string, ".", true );
+        final int size = tokenizer.countTokens();
+
+        m_components = new int[ ( size + 1 ) / 2 ];
+
+        for( int i = 0; i < m_components.length; i++ )
+        {
+            final String component = tokenizer.nextToken();
+            if( component.equals( "" ) )
+            {
+                throw new NumberFormatException( "Empty component in string" );
+            }
+
+            m_components[ i ] = Integer.parseInt( component );
+
+            //Strip '.' token
+            if( tokenizer.hasMoreTokens() )
+            {
+                tokenizer.nextToken();
+
+                //If it ended in a dot, throw an exception
+                if( !tokenizer.hasMoreTokens() )
+                {
+                    throw new NumberFormatException( "DeweyDecimal ended in a '.'" );
+                }
+            }
+        }
+    }
+
+    /**
+     * Return number of components in <code>DeweyDecimal</code>.
+     *
+     * @return the number of components in dewey decimal
+     */
+    public int getSize()
+    {
+        return m_components.length;
+    }
+
+    /**
+     * Return the component at specified index.
+     *
+     * @param index the index of components
+     * @return the value of component at index
+     */
+    public int get( final int index )
+    {
+        return m_components[ index ];
+    }
+
+    /**
+     * Return <code>true</code> if this <code>DeweyDecimal</code> is
+     * equal to the other <code>DeweyDecimal</code>.
+     *
+     * @param other the other DeweyDecimal
+     * @return true if equal to other DeweyDecimal, false otherwise
+     */
+    public boolean isEqual( final DeweyDecimal other )
+    {
+        final int max = Math.max( other.m_components.length, m_components.length );
+
+        for( int i = 0; i < max; i++ )
+        {
+            final int component1 = ( i < m_components.length ) ? m_components[ i ] : 0;
+            final int component2 = ( i < other.m_components.length ) ? other.m_components[ i ] : 0;
+
+            if( component2 != component1 )
+            {
+                return false;
+            }
+        }
+
+        return true; // Exact match
+    }
+
+    /**
+     * Return <code>true</code> if this <code>DeweyDecimal</code> is
+     * less than the other <code>DeweyDecimal</code>.
+     *
+     * @param other the other DeweyDecimal
+     * @return true if less than other DeweyDecimal, false otherwise
+     */
+    public boolean isLessThan( final DeweyDecimal other )
+    {
+        return !isGreaterThanOrEqual( other );
+    }
+
+    /**
+     * Return <code>true</code> if this <code>DeweyDecimal</code> is
+     * less than or equal to the other <code>DeweyDecimal</code>.
+     *
+     * @param other the other DeweyDecimal
+     * @return true if less than or equal to other DeweyDecimal, false otherwise
+     */
+    public boolean isLessThanOrEqual( final DeweyDecimal other )
+    {
+        return !isGreaterThan( other );
+    }
+
+    /**
+     * Return <code>true</code> if this <code>DeweyDecimal</code> is
+     * greater than the other <code>DeweyDecimal</code>.
+     *
+     * @param other the other DeweyDecimal
+     * @return true if greater than other DeweyDecimal, false otherwise
+     */
+    public boolean isGreaterThan( final DeweyDecimal other )
+    {
+        final int max = Math.max( other.m_components.length, m_components.length );
+
+        for( int i = 0; i < max; i++ )
+        {
+            final int component1 = ( i < m_components.length ) ? m_components[ i ] : 0;
+            final int component2 = ( i < other.m_components.length ) ? other.m_components[ i ] : 0;
+
+            if( component2 > component1 )
+            {
+                return false;
+            }
+            if( component2 < component1 )
+            {
+                return true;
+            }
+        }
+
+        return false; // Exact match
+    }
+
+    /**
+     * Return <code>true</code> if this <code>DeweyDecimal</code> is
+     * greater than or equal to the other <code>DeweyDecimal</code>.
+     *
+     * @param other the other DeweyDecimal
+     * @return true if greater than or equal to other DeweyDecimal, false otherwise
+     */
+    public boolean isGreaterThanOrEqual( final DeweyDecimal other )
+    {
+        final int max = Math.max( other.m_components.length, m_components.length );
+
+        for( int i = 0; i < max; i++ )
+        {
+            final int component1 = ( i < m_components.length ) ? m_components[ i ] : 0;
+            final int component2 = ( i < other.m_components.length ) ? other.m_components[ i ] : 0;
+
+            if( component2 > component1 )
+            {
+                return false;
+            }
+            if( component2 < component1 )
+            {
+                return true;
+            }
+        }
+
+        return true; // Exact match
+    }
+
+    /**
+     * Return string representation of <code>DeweyDecimal</code>.
+     *
+     * @return the string representation of DeweyDecimal.
+     */
+    public String toString()
+    {
+        final StringBuffer sb = new StringBuffer();
+
+        for( int i = 0; i < m_components.length; i++ )
+        {
+            if( i != 0 )
+            {
+                sb.append( '.' );
+            }
+            sb.append( m_components[ i ] );
+        }
+
+        return sb.toString();
+    }
+}