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.classfile;

import java.lang.ref.Reference;
import java.lang.ref.WeakReference;
import java.util.AbstractList;
import java.util.ArrayList;
import java.util.List;
import java.util.RandomAccess;

/**
 * Represents multiple class names.
 *
 * @since 2019/04/14
 */
public final class ClassNames
    extends AbstractList<ClassName>
    implements RandomAccess
{
    /** Names. */
    private final ClassName[] _names;
    
    /** Hash code. */
    private int _hash;
    
    /** String. */
    private Reference<String> _string;
    
    /**
     * Initializes the class names.
     *
     * @param __n The names.
     * @throws NullPointerException On null arguments.
     * @since 2019/04/14
     */
    public ClassNames(ClassName... __n)
        throws NullPointerException
    {
        for (ClassName n : (__n =
            (__n == null ? new ClassName[0] : __n.clone())))
            if (n == null)
                throw new NullPointerException("NARG");
            
        this._names = __n;
    }
    
    /**
     * Initializes the class names from the iterable.
     * 
     * @param __n The names.
     * @throws NullPointerException On null arguments.
     * @since 2021/01/13
     */
    public ClassNames(Iterable<ClassName> __n)
        throws NullPointerException
    {
        if (__n == null)
            throw new NullPointerException("NARG");
        
        List<ClassName> names = new ArrayList<>();
        for (ClassName name : __n)
            if (name == null)
                throw new NullPointerException("NARG");
            else
                names.add(name);
        
        this._names = names.<ClassName>toArray(new ClassName[names.size()]);
    }
    
    /**
     * {@inheritDoc}
     * @since 2019/04/14
     */
    @Override
    public final int hashCode()
    {
        int rv = this._hash;
        if (rv == 0)
            this._hash = (rv = super.hashCode());
        return rv;
    }
    
    /**
     * {@inheritDoc}
     * @since 2019/04/14
     */
    @Override
    public final ClassName get(int __i)
    {
        return this._names[__i];
    }
    
    /**
     * {@inheritDoc}
     * @since 2019/04/14
     */
    @Override
    public final int size()
    {
        return this._names.length;
    }
    
    /**
     * {@inheritDoc}
     * @since 2019/04/14
     */
    @Override
    public ClassName[] toArray()
    {
        return this._names.clone();
    }
    
    /**
     * {@inheritDoc}
     * @since 2019/04/14
     */
    @Override
    public final String toString()
    {
        Reference<String> ref = this._string;
        String rv;
        
        if (ref == null || null == (rv = ref.get()))
            this._string = new WeakReference<>((rv = super.toString()));
        
        return rv;
    }
}