| /* |
| * 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.functor.adapter; |
| |
| import java.io.Serializable; |
| |
| import org.apache.commons.functor.NullaryFunction; |
| import org.apache.commons.functor.NullaryPredicate; |
| import org.apache.commons.lang3.Validate; |
| |
| /** |
| * Adapts a <code>Boolean</code>-valued |
| * {@link NullaryFunction NullaryFunction} to the |
| * {@link NullaryPredicate NullaryPredicate} interface. |
| * <p/> |
| * Note that although this class implements |
| * {@link Serializable}, a given instance will |
| * only be truly <code>Serializable</code> if the |
| * underlying functor is. Attempts to serialize |
| * an instance whose delegate is not |
| * <code>Serializable</code> will result in an exception. |
| * |
| * @version $Revision: 1365377 $ $Date: 2012-07-24 21:59:23 -0300 (Tue, 24 Jul 2012) $ |
| */ |
| public final class NullaryFunctionNullaryPredicate implements NullaryPredicate, Serializable { |
| |
| /** |
| * serialVersionUID declaration. |
| */ |
| private static final long serialVersionUID = 6564796937660102222L; |
| /** The {@link NullaryFunction NullaryFunction} I'm wrapping. */ |
| private final NullaryFunction<Boolean> function; |
| |
| /** |
| * Create a new NullaryFunctionNullaryPredicate. |
| * @param function to adapt |
| */ |
| public NullaryFunctionNullaryPredicate(NullaryFunction<Boolean> function) { |
| this.function = Validate.notNull(function, "NullaryFunction argument was null"); |
| } |
| |
| /** |
| * Returns the <code>boolean</code> value of the non-<code>null</code> |
| * <code>Boolean</code> returned by the {@link NullaryFunction#evaluate evaluate} |
| * method of my underlying function. |
| * {@inheritDoc} |
| */ |
| public boolean test() { |
| return function.evaluate().booleanValue(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public boolean equals(Object that) { |
| return that == this || (that instanceof NullaryFunctionNullaryPredicate |
| && equals((NullaryFunctionNullaryPredicate) that)); |
| } |
| |
| /** |
| * Learn whether another NullaryFunctionNullaryPredicate is equal to this. |
| * @param that NullaryFunctionNullaryPredicate to test |
| * @return boolean |
| */ |
| public boolean equals(NullaryFunctionNullaryPredicate that) { |
| return null != that && function.equals(that.function); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public int hashCode() { |
| int hash = "NullaryFunctionNullaryPredicate".hashCode(); |
| hash ^= function.hashCode(); |
| return hash; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public String toString() { |
| return "NullaryFunctionNullaryPredicate<" + function + ">"; |
| } |
| |
| /** |
| * Adapt a NullaryFunction as a NullaryPredicate. |
| * @param function to adapt |
| * @return NullaryFunctionNullaryPredicate |
| */ |
| public static NullaryFunctionNullaryPredicate adapt(NullaryFunction<Boolean> function) { |
| return null == function ? null : new NullaryFunctionNullaryPredicate(function); |
| } |
| } |