root/trunk/src/java/org/jcoderz/commons/util/ArraysUtil.java

/*
 * $Id$
 *
 * Copyright 2006, The jCoderZ.org Project. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * 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.
 *    * Neither the name of the jCoderZ.org Project nor the names of
 *      its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written
 *      permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS 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 REGENTS AND 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.
 */
package org.jcoderz.commons.util;



/**
 * This class contains a static factory that allows arrays to be viewed as
 * lists.
 * 
 * @author Michael Griffel
 */
public final class ArraysUtil
{
   /**
    * No constructor for util class.
    */
   private ArraysUtil ()
   {
      // No instances allowed - contains only static utility functions.
   }
   
   
   /**
    * Returns a string representation of the contents of the specified array. 
    * If the array contains other arrays as elements, they are converted 
    * to strings by the {@link Object#toString}method inherited 
    * from <tt>Object</tt>, which describes their <i>identities</i> 
    * rather than their contents.
    * <p>
    * The value returned by this method is equal to the value that would be
    * returned by <tt>Arrays.asList(a).toString()</tt>, unless <tt>array</tt>
    * is <tt>null</tt>, in which case <tt>"null"</tt> is returned.
    * <p>
    * This method is useful to dump the content of the array in a tracing 
    * method, e.g.:
    * <pre>
    * logger.entering(CLASSNAME, "foo(Object[])", ArraysUtil.toString(array));
    * </pre>
    * @param array The array whose string representation to return.  
    * @return A string representation of <tt>array</tt>.
    */
   public static String toString (Object[] array)
   {
      final String result;
      
      if (array == null)
      {
         result = "null";
      }
      else if (array.length == 0)
      {
         result = "[]";
      }
      else
      {
         final StringBuffer buf = new StringBuffer();
         for (int i = 0; i < array.length; i++)
         {
            if (i == 0)
            {
               buf.append('[');
            }
            else
            {
               buf.append(", ");
            }
            if (array[i] instanceof Object[]) 
            {
               buf.append(ArraysUtil.toString((Object[]) array[i]));
            }
            else
            {
               buf.append(String.valueOf(array[i]));
            }
         }
         buf.append(']');
         result = buf.toString();
      }
      return result;
   }
}