modules/cldc-compact/src/main/java/cc/squirreljme/runtime/cldc/util/ReferenceIterator.java
// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// Multi-Phasic Applications: 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 cc.squirreljme.runtime.cldc.util;
import java.lang.ref.Reference;
import java.util.Iterator;
/**
* Wraps a reference based iterator and exposes the elements underneath.
*
* If the reference was garbage collected then {@link IllegalStateException}
* will be thrown.
*
* @param <T> The element type.
* @since 2022/08/27
*/
public final class ReferenceIterator<T>
implements Iterator<T>
{
/** The iterator used. */
protected final Iterator<Reference<T>> iterator;
/**
* Initializes the iterator wrapper.
*
* @param __iterator The iterator.
* @throws NullPointerException On null arguments.
* @since 2022/08/27
*/
public ReferenceIterator(Iterator<Reference<T>> __iterator)
throws NullPointerException
{
if (__iterator == null)
throw new NullPointerException("NARG");
this.iterator = __iterator;
}
/**
* {@inheritDoc}
* @since 2022/08/27
*/
@Override
public boolean hasNext()
{
return this.iterator.hasNext();
}
/**
* {@inheritDoc}
* @since 2022/08/27
*/
@Override
public T next()
{
Reference<T> ref = this.iterator.next();
if (ref == null)
return null;
T rv = ref.get();
if (rv == null)
throw new IllegalStateException("GCGC");
return rv;
}
/**
* {@inheritDoc}
* @since 2022/08/27
*/
@Override
public void remove()
{
this.iterator.remove();
}
}