/*
 * Zorbage: an Algebraic data hierarchy for use in numeric processing.
 *
 * Copyright (C) 2016-2018 Barry DeZonia
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package nom.bdezonia.zorbage.type.storage;

import nom.bdezonia.zorbage.procedure.Procedure2;
import nom.bdezonia.zorbage.type.algebra.Algebra;

/**
 * 
 * @author Barry DeZonia
 *
 */
public class TransformedDataSource<T extends IndexedDataSource<T,U>, U, V extends IndexedDataSource<V,W>, W> implements IndexedDataSource<V,W>
{
	private final IndexedDataSource<?,U> uCollection;
	private final Algebra<?, U> uAlg;
	private final Procedure2<W,U> wToU;
	private final Procedure2<U,W> uToW;
	
	/**
	 * 
	 * @param uCollection
	 * @param uAlg
	 * @param uToW
	 * @param wToU
	 */
	public TransformedDataSource(IndexedDataSource<?,U> uCollection, Algebra<?,U> uAlg, Procedure2<U,W> uToW, Procedure2<W,U> wToU) {
		this.uCollection = uCollection;
		this.uAlg = uAlg;
		this.uToW = uToW;
		this.wToU = wToU;
	}

	/**
	 * 
	 */
	@SuppressWarnings("unchecked") // TODO: unchecked cast required. I can't find workaround. 
	@Override
	public V duplicate() {
		// shallow copy
		return (V) new TransformedDataSource<T,U,V,W>(uCollection, uAlg, uToW, wToU);
	}

	/**
	 * 
	 */
	@Override
	public void set(long index, W value) {
		U tmp = tmpU.get();
		wToU.call(value, tmp);
		uCollection.set(index, tmp);
	}

	/**
	 * 
	 */
	@Override
	public void get(long index, W value) {
		U tmp = tmpU.get();
		uCollection.get(index, tmp);
		uToW.call(tmp, value);
	}

	/**
	 * 
	 */
	@Override
	public long size() {
		return uCollection.size();
	}
	
	private ThreadLocal<U> tmpU = new ThreadLocal<U>() {
		@Override
		protected U initialValue() {
			return uAlg.construct();
		}
	};
}

@@ -2862,16 +2862,22 @@
 private 
+final 
 ThreadLo

Mark an instance variable as final