stringmorpher.java

iBATIS似乎已远离众说纷纭的OR框架之列

/*
 * Copyright 2006 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.sf.ezmorph.object;

import net.sf.ezmorph.MorphException;
import net.sf.ezmorph.ObjectMorpher;

/**
 * Morphs to a String.
 *
 * @author Andres Almiray <[e-mail]>
 */
public final class StringMorpher implements ObjectMorpher
{
   private static final StringMorpher INSTANCE = new StringMorpher();

   public static StringMorpher getInstance()
   {
      return INSTANCE;
   }

   private StringMorpher()
   {
   }

   public boolean equals( Object obj )
   {
      return INSTANCE == obj;
   }

   public int hashCode()
   {
      return 42 + getClass().hashCode();
   }

   public Object morph( Object value )
   {
      if( value == null ){
         return null;
      }

      if( !supports( value.getClass() ) ){
         throw new MorphException( "Class not supported. " + value.getClass() );
      }

      if( String.class.isAssignableFrom( value.getClass() ) ){
         return (String) value;
      }

      return String.valueOf( value );
   }

   public Class morphsTo()
   {
      return String.class;
   }

   /**
    * Returns true if the Morpher supports conversion from this Class.<br>
    * Supports any type that is not an Array.
    *
    * @param clazz the source Class
    * @return true if clazz is supported by this morpher, false otherwise.
    */
   public boolean supports( Class clazz )
   {
      return !clazz.isArray();
   }
}