/*
* Redberry: symbolic tensor computations.
*
* Copyright (c) 2010-2014:
* Stanislav Poslavsky <stvlpos@mail.ru>
* Bolotin Dmitriy <bolotin.dmitriy@gmail.com>
*
* This file is part of Redberry.
*
* Redberry is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Redberry is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Redberry. If not, see <http://www.gnu.org/licenses/>.
*/
package cc.redberry.core.transformations;
import cc.redberry.core.tensor.Tensor;
import cc.redberry.core.tensor.iterator.TraverseGuide;
import cc.redberry.core.tensor.iterator.TraverseState;
import cc.redberry.core.tensor.iterator.TreeTraverseIterator;
/**
*
* @author Dmitry Bolotin
* @author Stanislav Poslavsky
*/
public class Transformer implements Transformation {
private final TraverseState state;
private final Transformation[] transformations;
private final TraverseGuide guide;
public Transformer(TraverseState state, Transformation[] transformations, TraverseGuide guide) {
this.state = state;
this.transformations = transformations;
this.guide = guide;
}
public Transformer(TraverseState state, Transformation[] transformations) {
this.state = state;
this.transformations = transformations;
this.guide = TraverseGuide.ALL;
}
@Override
public Tensor transform(Tensor t) {
TreeTraverseIterator iterator = new TreeTraverseIterator(t, guide);
TraverseState currentState;
Tensor currentTensor, newTensor;
while ((currentState = iterator.next()) != null) {
if (currentState != state)
continue;
currentTensor = newTensor = iterator.current();
for (Transformation transformation : transformations)
newTensor = transformation.transform(newTensor);
if (currentTensor != newTensor)
iterator.set(newTensor);
}
return iterator.result();
}
}