ResettableNullHandler.java

/*license*\
   XBN-Java: Copyright (C) 2014, Jeff Epstein (aliteralmind __DASH__ github __AT__ yahoo __DOT__ com)

   This software is dual-licensed under the:
   - Lesser General Public License (LGPL) version 3.0 or, at your option, any later version;
   - Apache Software License (ASL) version 2.0.

   Either license may be applied at your discretion. More information may be found at
   - http://en.wikipedia.org/wiki/Multi-licensing.

   The text of both licenses is available in the root directory of this project, under the names "LICENSE_lgpl-3.0.txt" and "LICENSE_asl-2.0.txt". The latest copies may be downloaded at:
   - LGPL 3.0: https://www.gnu.org/licenses/lgpl-3.0.txt
   - ASL 2.0: http://www.apache.org/licenses/LICENSE-2.0.txt
\*license*/
package  com.github.xbn.util.copyval;
/**
   <p>Mutable {@code NullHandler} for static internal use only.</p>

 * @since  0.1.0
 * @author  Copyright (C) 2014, Jeff Epstein ({@code aliteralmind __DASH__ github __AT__ yahoo __DOT__ com}), dual-licensed under the LGPL (version 3.0 or later) or the ASL (version 2.0). See source code for details. <a href="http://xbnjava.aliteralmind.com">{@code http://xbnjava.aliteralmind.com}</a>, <a href="https://github.com/aliteralmind/xbnjava">{@code https://github.com/aliteralmind/xbnjava}</a>
 **/
public class ResettableNullHandler<O> implements NullHandler<O>  {
   private O e = null;
   public ResettableNullHandler(O non_nullRplcmnt)  {
      nonNullValue(non_nullRplcmnt);
   }
   /**
      <p>Create a new {@code ResettableNullHandler} as a duplicate of another.</p>

      <p>This<ol>
         <li>YYY</li>
      </ol></p>

    * @param  to_copy  May not be {@code null}.
    * @see  #getObjectCopy()
    */
   public ResettableNullHandler(ResettableNullHandler<O> to_copy)  {
      nonNullValue(to_copy.getNonNull());
   }
   public final ResettableNullHandler nonNullValue(O non_nullRplcmnt)  {
      if(non_nullRplcmnt == null)  {
         throw  new NullPointerException("non_nullRplcmnt");
      }
      e = non_nullRplcmnt;
      return  this;
   }
   public ActionForNull getAction()  {
      return  ActionForNull.USE_NON_NULL;
   }
   public final boolean doCrash()  {
      return  false;
   }
   public final boolean doUseNull()  {
      return  false;
   }
   public final boolean doDelete()  {
      return  false;
   }
   public final boolean doUseNonNull()  {
      return  true;
   }
   public final O getNonNull()  {
      return  e;
   }
   /**
      <p>Duplicate this {@code ResettableNullHandler}.</p>

    * @return  <code>(new {@link #ResettableNullHandler(ResettableNullHandler) ResettableNullHandler}<O>(this))</code>
    */
   public NullHandler<O> getObjectCopy()  {
      return  (new ResettableNullHandler<O>(this));
   }
   public String toString()  {
      return  "getNonNull()=[" + getNonNull() + "]";
   }

}