- /*
- * Copyright 2001-2004 The Apache Software Foundation
- *
- * 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.apache.commons.collections.functors;
-
- import java.io.Serializable;
-
- import org.apache.commons.collections.Closure;
- import org.apache.commons.collections.Predicate;
-
- /**
- * Closure implementation acts as an if statement calling one or other closure
- * based on a predicate.
- *
- * @since Commons Collections 3.0
- * @version $Revision: 1.6 $ $Date: 2004/05/16 11:47:38 $
- *
- * @author Stephen Colebourne
- */
- public class IfClosure implements Closure, Serializable {
-
- /** Serial version UID */
- static final long serialVersionUID = 3518477308466486130L;
-
- /** The test */
- private final Predicate iPredicate;
- /** The closure to use if true */
- private final Closure iTrueClosure;
- /** The closure to use if false */
- private final Closure iFalseClosure;
-
- /**
- * Factory method that performs validation.
- *
- * @param predicate predicate to switch on
- * @param trueClosure closure used if true
- * @param falseClosure closure used if false
- * @return the <code>if</code> closure
- * @throws IllegalArgumentException if any argument is null
- */
- public static Closure getInstance(Predicate predicate, Closure trueClosure, Closure falseClosure) {
- if (predicate == null) {
- throw new IllegalArgumentException("Predicate must not be null");
- }
- if (trueClosure == null || falseClosure == null) {
- throw new IllegalArgumentException("Closures must not be null");
- }
- return new IfClosure(predicate, trueClosure, falseClosure);
- }
-
- /**
- * Constructor that performs no validation.
- * Use <code>getInstance</code> if you want that.
- *
- * @param predicate predicate to switch on, not null
- * @param trueClosure closure used if true, not null
- * @param falseClosure closure used if false, not null
- */
- public IfClosure(Predicate predicate, Closure trueClosure, Closure falseClosure) {
- super();
- iPredicate = predicate;
- iTrueClosure = trueClosure;
- iFalseClosure = falseClosure;
- }
-
- /**
- * Executes the true or false closure accoring to the result of the predicate.
- *
- * @param input the input object
- */
- public void execute(Object input) {
- if (iPredicate.evaluate(input) == true) {
- iTrueClosure.execute(input);
- } else {
- iFalseClosure.execute(input);
- }
- }
-
- /**
- * Gets the predicate.
- *
- * @return the predicate
- * @since Commons Collections 3.1
- */
- public Predicate getPredicate() {
- return iPredicate;
- }
-
- /**
- * Gets the closure called when true.
- *
- * @return the closure
- * @since Commons Collections 3.1
- */
- public Closure getTrueClosure() {
- return iTrueClosure;
- }
-
- /**
- * Gets the closure called when false.
- *
- * @return the closure
- * @since Commons Collections 3.1
- */
- public Closure getFalseClosure() {
- return iFalseClosure;
- }
-
- }