net.shibboleth.utilities.java.support.logic.AllMatchPredicate Maven / Gradle / Ivy
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* Licensed to the University Corporation for Advanced Internet Development,
* Inc. (UCAID) under one or more contributor license agreements. See the
* NOTICE file distributed with this work for additional information regarding
* copyright ownership. The UCAID licenses this file to You 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 net.shibboleth.utilities.java.support.logic;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import com.google.common.base.Predicate;
/**
* A {@link Predicate} that checks that all items in an {@link Iterable} match a given target predicate. If the given
* {@link Iterable} is null or contains no items this method will return false, otherwise it passes each
* {@link Iterable} value to the target predicate, even if those values are null. The first
* false returned by the target predicate stops evaluation and causes this predicate to return (i.e., it
* short-circuits the evaluation).
*
* @param type of object upon which this predicate operates
*/
public class AllMatchPredicate implements Predicate> {
/** The predicate applied to each value of the {@link Iterable}. */
private final Predicate predicate;
/**
* Constructor.
*
* @param target the target predicate against which all {@link Iterable} elements are evaluated
*/
public AllMatchPredicate(@Nonnull final Predicate target) {
predicate = Constraint.isNotNull(target, "Target predicate can not be null");
}
/** {@inheritDoc} */
public boolean apply(@Nullable final Iterable inputs) {
if (inputs == null) {
return false;
}
boolean matchedAll = false;
for (final T input : inputs) {
if (!predicate.apply(input)) {
return false;
} else {
matchedAll = true;
}
}
return matchedAll;
}
}