| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF 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 org.apache.commons.collections4.functors; |
| |
| import java.util.Objects; |
| |
| import org.apache.commons.collections4.Closure; |
| import org.apache.commons.collections4.Predicate; |
| |
| /** |
| * Closure implementation that executes a closure repeatedly until a condition is met, |
| * like a do-while or while loop. |
| * <p> |
| * <b>WARNING:</b> from v4.1 onwards this class will <b>not</b> be serializable anymore |
| * in order to prevent potential remote code execution exploits. Please refer to |
| * <a href="https://issues.apache.org/jira/browse/COLLECTIONS-580">COLLECTIONS-580</a> |
| * for more details. |
| * </p> |
| * |
| * @since 3.0 |
| */ |
| public class WhileClosure<E> implements Closure<E> { |
| |
| /** |
| * Factory method that performs validation. |
| * |
| * @param <E> the type that the closure acts on |
| * @param predicate the predicate used to evaluate when the loop terminates, not null |
| * @param closure the closure to execute, not null |
| * @param doLoop true to act as a do-while loop, always executing the closure once |
| * @return the {@code while} closure |
| * @throws NullPointerException if the predicate or closure is null |
| */ |
| public static <E> Closure<E> whileClosure(final Predicate<? super E> predicate, |
| final Closure<? super E> closure, final boolean doLoop) { |
| return new WhileClosure<>(Objects.requireNonNull(predicate, "predicate"), |
| Objects.requireNonNull(closure, "closure"), doLoop); |
| } |
| /** The test condition */ |
| private final Predicate<? super E> iPredicate; |
| /** The closure to call */ |
| private final Closure<? super E> iClosure; |
| |
| /** The flag, true is a do loop, false is a while */ |
| private final boolean iDoLoop; |
| |
| /** |
| * Constructor that performs no validation. |
| * Use {@code whileClosure} if you want that. |
| * |
| * @param predicate the predicate used to evaluate when the loop terminates, not null |
| * @param closure the closure to execute, not null |
| * @param doLoop true to act as a do-while loop, always executing the closure once |
| */ |
| public WhileClosure(final Predicate<? super E> predicate, final Closure<? super E> closure, final boolean doLoop) { |
| iPredicate = predicate; |
| iClosure = closure; |
| iDoLoop = doLoop; |
| } |
| |
| /** |
| * Executes the closure until the predicate is false. |
| * |
| * @param input the input object |
| */ |
| @Override |
| public void execute(final E input) { |
| if (iDoLoop) { |
| iClosure.execute(input); |
| } |
| while (iPredicate.evaluate(input)) { |
| iClosure.execute(input); |
| } |
| } |
| |
| /** |
| * Gets the closure. |
| * |
| * @return the closure |
| * @since 3.1 |
| */ |
| public Closure<? super E> getClosure() { |
| return iClosure; |
| } |
| |
| /** |
| * Gets the predicate in use. |
| * |
| * @return the predicate |
| * @since 3.1 |
| */ |
| public Predicate<? super E> getPredicate() { |
| return iPredicate; |
| } |
| |
| /** |
| * Is the loop a do-while loop. |
| * |
| * @return true is do-while, false if while |
| * @since 3.1 |
| */ |
| public boolean isDoLoop() { |
| return iDoLoop; |
| } |
| |
| } |