/*
* Copyright 2002-2013 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.util;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.springframework.expression.MethodFilter;
import org.springframework.util.Assert;
/**
* A {@link MethodFilter} implementation that will always return
* the same Method instance within a single-element list if it is
* present in the candidate list. If the Method is not present
* in the candidate list, it will return an empty list.
*
* @author Mark Fisher
* @author Gary Russell
* @since 2.0
*/
public class FixedMethodFilter implements MethodFilter {
private final Method method;
public FixedMethodFilter(Method method) {
Assert.notNull(method, "method must not be null");
this.method = method;
}
public List<Method> filter(List<Method> methods) {
if (methods != null && methods.contains(this.method)) {
List<Method> filteredList = new ArrayList<Method>(1);
filteredList.add(this.method);
return filteredList;
}
return Collections.<Method>emptyList();
}
}