org.jboss.cdi.tck.util.TransformationUtils Maven / Gradle / Ivy
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* Copyright 2010, Red Hat, Inc., and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* 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.jboss.cdi.tck.util;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
public final class TransformationUtils {
/**
* @param the input type of this function
* @param the output type of this function
*/
public static interface Function {
/**
* Returns the result of applying this function to {@code input}.
*/
T apply(F input);
}
/**
* Returns a list that applies {@code function} to each element of {@code fromCollection}.
*
* @throws IllegalArgumentException in case of a null argument
*/
public static List transform(final Function function, final Collection fromCollection) {
checkNotNull(fromCollection);
checkNotNull(function);
List result = new ArrayList(fromCollection.size());
for (F element : fromCollection) {
result.add(function.apply(element));
}
return result;
}
/**
* Returns a list that applies {@code function} to each element of {@code inputElements}.
*/
@SafeVarargs
public static List transform(final Function function, final F... inputElements) {
return transform(function, Arrays.asList(inputElements));
}
private static void checkNotNull(Object o) {
if (o == null) {
throw new IllegalArgumentException("Null argument.");
}
}
}