/*

  *  Copyright 2003-2004 The Apache Software Foundation

  *

  *  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 org.apache.commons.convert1.util;

 import java.util.ArrayList;

 import java.util.Iterator;

 import java.util.List;

 /**

  * An inheritence sequence. The target class is first, 

  * followed by its superclass and its interfaces. Then the 

  * lookup recurses through the superclass and interfaces 

  * with the same strategy. 

  * It is ensured that java.lang.Object is last in the sequence.

  */

 public class BasicInheritor implements Inheritor {

     private Class clazz;

     public BasicInheritor() {

     }

     public BasicInheritor(Class clazz) {

         setTarget(clazz);

     }

     public void setTarget(Class clazz) {

         this.clazz = clazz;

     }

     public Class getTarget() {

         return clazz;

     }

     public Iterator iterator() {

         List list = new ArrayList();

         addToList(list, clazz);

         addClassParents(list, clazz);

         list.add( Object.class );

         return list.iterator();

     }

     private void addClassParents(List list, Class clazz) {

         if (clazz == null) {

             return;

         }

         Class superclass = clazz.getSuperclass();

         addToList(list, superclass);

         Class[] interfaces = clazz.getInterfaces();

         for (int i = 0; i < interfaces.length; i++) {

             addToList(list, interfaces[i]);

         }

         for (int i = 0; i < interfaces.length; i++) {

             addClassParents(list, interfaces[i]);

         }

         addClassParents(list, superclass);

     }

     private void addToList(List list, Class clazz) {

         if( clazz == null ) {

             return;

         }

         if( Object.class == clazz ) {

             return;

         }

         if( list.contains( clazz ) ) {

             return;

         }

         list.add(clazz);

     }

 }