/*
* Copyright 2012 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.planner.examples.nqueens.solver.score;
import java.util.ArrayList;
import java.util.List;
import org.drools.planner.core.score.buildin.simple.DefaultSimpleScore;
import org.drools.planner.core.score.buildin.simple.SimpleScore;
import org.drools.planner.core.score.director.incremental.AbstractIncrementalScoreCalculator;
import org.drools.planner.examples.nqueens.domain.NQueens;
import org.drools.planner.examples.nqueens.domain.Queen;
import org.drools.planner.examples.nqueens.domain.Row;
public class NQueensBasicIncrementalScoreCalculator extends AbstractIncrementalScoreCalculator<NQueens> {
private List<Queen> insertedQueenList;
private int score;
public void resetWorkingSolution(NQueens nQueens) {
insertedQueenList = new ArrayList<Queen>(nQueens.getN());
score = 0;
for (Queen queen : nQueens.getQueenList()) {
insert(queen);
}
}
public void beforeEntityAdded(Object entity) {
// Do nothing
}
public void afterEntityAdded(Object entity) {
insert((Queen) entity);
}
public void beforeAllVariablesChanged(Object entity) {
retract((Queen) entity);
}
public void afterAllVariablesChanged(Object entity) {
insert((Queen) entity);
}
public void beforeVariableChanged(Object entity, String variableName) {
retract((Queen) entity);
}
public void afterVariableChanged(Object entity, String variableName) {
insert((Queen) entity);
}
public void beforeEntityRemoved(Object entity) {
retract((Queen) entity);
}
public void afterEntityRemoved(Object entity) {
// Do nothing
}
private void insert(Queen queen) {
Row row = queen.getRow();
if (row != null) {
for (Queen otherQueen : insertedQueenList) {
if (queen.getRowIndex() == otherQueen.getRowIndex()) {
score--;
}
if (queen.getAscendingDiagonalIndex() == otherQueen.getAscendingDiagonalIndex()) {
score--;
}
if (queen.getDescendingDiagonalIndex() == otherQueen.getDescendingDiagonalIndex()) {
score--;
}
}
insertedQueenList.add(queen);
}
}
private void retract(Queen queen) {
Row row = queen.getRow();
if (row != null) {
insertedQueenList.remove(queen);
for (Queen otherQueen : insertedQueenList) {
if (queen.getRowIndex() == otherQueen.getRowIndex()) {
score++;
}
if (queen.getAscendingDiagonalIndex() == otherQueen.getAscendingDiagonalIndex()) {
score++;
}
if (queen.getDescendingDiagonalIndex() == otherQueen.getDescendingDiagonalIndex()) {
score++;
}
}
}
}
public SimpleScore calculateScore() {
return DefaultSimpleScore.valueOf(score);
}
}