/*
* Copyright 2002-2017 the original author or authors.
*
* 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.springframework.integration.aggregator;
import org.springframework.expression.Expression;
import org.springframework.integration.store.MessageGroup;
import org.springframework.integration.util.AbstractExpressionEvaluator;
import org.springframework.util.Assert;
/**
* A {@link ReleaseStrategy} that evaluates an expression.
*
* @author Dave Syer
* @author Artem Bilan
*/
public class ExpressionEvaluatingReleaseStrategy extends AbstractExpressionEvaluator implements ReleaseStrategy {
private final Expression expression;
public ExpressionEvaluatingReleaseStrategy(String expression) {
Assert.hasText(expression, "'expression' must not be empty");
this.expression = EXPRESSION_PARSER.parseExpression(expression);
}
public ExpressionEvaluatingReleaseStrategy(Expression expression) {
Assert.notNull(expression, "'expression' must not be null");
this.expression = expression;
}
/**
* Evaluate the expression provided on the {@link MessageGroup}
* and return the result (must be boolean).
*/
public boolean canRelease(MessageGroup messages) {
return evaluateExpression(this.expression, messages, Boolean.class);
}
}