package org.exolab.castor.mapping.loader.collection.handler;
   
   import java.lang.reflect.Array;
   import java.util.Enumeration;
   
   import org.exolab.castor.mapping.CollectionHandler;
   import org.exolab.castor.mapping.loader.CollectionHandlers;
   import org.exolab.castor.mapping.loader.J1CollectionHandlers.ArrayEnumerator;
   
  public final class ArrayCollectionHandler<T> implements CollectionHandler<T> {
     public Object add(Object collection, T object) {
        if (collection == null) {
  
           // If the collection is of primitive type, the instantiation
           // (if it was null) is handled in the FieldHandlerImpl. We
           // can rely here that we deal only with array of object.
           Object newArray = Array.newInstance(object.getClass(), 1);
           Array.set(newArray, 0, object);
           return newArray;
        }
  
        Class<?> type = collection.getClass();
        if (!type.isArray()) {
           String err = "J1CollectionHandlers.array#add: type "
                 + "mismatch, expecting an array, instead received: ";
           err += type.getName();
           throw new IllegalArgumentException(err);
        }
  
        type = type.getComponentType();
  
        Object newArray = Array.newInstance(type, Array.getLength(collection) + 1);
  
        for (int i = 0; i < Array.getLength(collection); ++i)
           Array.set(newArray, i, Array.get(collection, i));
  
        Array.set(newArray, Array.getLength(collection), object);
  
        return newArray;
  
     }
  
     public Enumeration<T> elements(Object collection) {
        if (collection == null)
           return new CollectionHandlers.EmptyEnumerator<T>();
        return new ArrayEnumerator<T>(collection);
     }
  
     public int size(Object collection) {
        if (collection == null)
           return 0;
        return Array.getLength(collection);
     }
  
     public Object clear(Object collection) {
        if (collection == null) {
           return null;
        }
        Class<?> type = collection.getClass();
        if (!type.isArray()) {
           String err = "J1CollectionHandlers.array#add: type "
                 + "mismatch, expecting an array, instead received: ";
           err += type.getName();
           throw new IllegalArgumentException(err);
        }
        type = type.getComponentType();
        return Array.newInstance(type, 0);
     }
  
     public String toString() {
        return "Object[]";
     }
  }