/*
* =============================================================================
*
* Copyright (c) 2011-2014, The THYMELEAF team (http://www.thymeleaf.org)
*
* 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.thymeleaf.standard.expression;
import java.math.BigDecimal;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.thymeleaf.Configuration;
import org.thymeleaf.TemplateEngine;
import org.thymeleaf.context.IProcessingContext;
import org.thymeleaf.exceptions.TemplateProcessingException;
import org.thymeleaf.util.EvaluationUtil;
/**
*
* @author Daniel Fernández
*
* @since 1.1
*
*
*/
public final class SubtractionExpression extends AdditionSubtractionExpression {
private static final long serialVersionUID = 4125686854902098944L;
private static final Logger logger = LoggerFactory.getLogger(SubtractionExpression.class);
public SubtractionExpression(final IStandardExpression left, final IStandardExpression right) {
super(left, right);
}
@Override
public String getStringRepresentation() {
return getStringRepresentation(SUBTRACTION_OPERATOR);
}
static Object executeSubtraction(final Configuration configuration, final IProcessingContext processingContext,
final SubtractionExpression expression, final StandardExpressionExecutionContext expContext) {
if (logger.isTraceEnabled()) {
logger.trace("[THYMELEAF][{}] Evaluating subtraction expression: \"{}\"", TemplateEngine.threadIndex(), expression.getStringRepresentation());
}
Object leftValue = expression.getLeft().execute(configuration, processingContext, expContext);
Object rightValue = expression.getRight().execute(configuration, processingContext, expContext);
if (leftValue == null) {
leftValue = "null";
}
if (rightValue == null) {
rightValue = "null";
}
final BigDecimal leftNumberValue = EvaluationUtil.evaluateAsNumber(leftValue);
final BigDecimal rightNumberValue = EvaluationUtil.evaluateAsNumber(rightValue);
if (leftNumberValue != null && rightNumberValue != null) {
// Addition will act as a mathematical 'plus'
return leftNumberValue.subtract(rightNumberValue);
}
throw new TemplateProcessingException(
"Cannot execute subtraction: operands are \"" + LiteralValue.unwrap(leftValue) + "\" and \"" + LiteralValue.unwrap(rightValue) + "\"");
}
}