SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the Mozilla Public License Version 2.0.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package net.multiphasicapps.collections;

import java.io.Closeable;
import java.io.IOException;
import java.util.ArrayList;

/**
 * This is based on top of {@link ArrayList} and is the same interface except
 * that it is {@link Closeable} and on close will attempt to close all
 * elements within the list.
 *
 * @since 2017/11/28
 */
public class CloseableList<T extends Closeable>
    extends ArrayList<T>
    implements Closeable
{
    /**
     * {@inheritDoc}
     * @since 2017/11/28
     */
    @Override
    public void close()
        throws IOException
    {
        int count = 0;
        IOException defer = null;
        for (int i = 0, n = this.size(); i < n; i++)
            try
            {
                T v = this.get(i);
                if (v != null)
                    v.close();
            }
            catch (IOException e)
            {
                if (defer == null)
                    defer = e;
                count++;
            }
        
        /* {@squirreljme.error AC01 There was at least one exception which
        occurred while closing the list. (The number of exceptions thrown)} */
        if (defer != null)
            throw new IOException(String.format("AC01 %d", count), defer);
    }
    
    /**
     * Adds the specified item to the list and returns it.
     *
     * @param __t The element to add.
     * @return {@code __t}.
     * @since 2017/11/28
     */
    public final T addThis(T __t)
    {
        this.add(__t);
        return __t;
    }
    
    /**
     * Adds the specified item to the list and returns it.
     *
     * @param <E> The class to cast to.
     * @param __t The element to add.
     * @param __cl The class to cast to on return.
     * @return {@code __t} cast to {@code E}.
     * @throws NullPointerException If no class was specified.
     * @since 2017/11/28
     */
    public final <E extends T> E addThis(E __t, Class<E> __cl)
        throws NullPointerException
    {
        if (__cl == null)
            throw new NullPointerException("NARG");
        
        this.add(__t);
        return __cl.cast(__t);
    }
}