001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.functor.adapter;
018
019 import java.io.Serializable;
020
021 import org.apache.commons.functor.BinaryProcedure;
022 import org.apache.commons.functor.UnaryProcedure;
023
024 /**
025 * Adapts a
026 * {@link UnaryProcedure UnaryProcedure}
027 * to the
028 * {@link BinaryProcedure BinaryProcedure} interface
029 * by ignoring the second binary argument.
030 * <p/>
031 * Note that although this class implements
032 * {@link Serializable}, a given instance will
033 * only be truly <code>Serializable</code> if the
034 * underlying functor is. Attempts to serialize
035 * an instance whose delegate is not
036 * <code>Serializable</code> will result in an exception.
037 *
038 * @param <L> the left argument type.
039 * @param <R> the right argument type.
040 * @version $Revision: 1157617 $ $Date: 2011-08-14 21:53:50 +0200 (Sun, 14 Aug 2011) $
041 * @author Rodney Waldhoff
042 */
043 public final class IgnoreRightProcedure<L, R> implements BinaryProcedure<L, R>, Serializable {
044 /**
045 * serialVersionUID declaration.
046 */
047 private static final long serialVersionUID = -7374293905310619206L;
048 /** The {@link UnaryProcedure UnaryProcedure} I'm wrapping. */
049 private final UnaryProcedure<? super L> procedure;
050
051 /**
052 * Create a new IgnoreRightProcedure.
053 * @param procedure UnaryProcedure to adapt
054 */
055 public IgnoreRightProcedure(UnaryProcedure<? super L> procedure) {
056 if (procedure == null) {
057 throw new IllegalArgumentException("UnaryProcedure argument was null");
058 }
059 this.procedure = procedure;
060 }
061
062 /**
063 * {@inheritDoc}
064 */
065 public void run(L left, R right) {
066 procedure.run(left);
067 }
068
069 /**
070 * {@inheritDoc}
071 */
072 public boolean equals(Object that) {
073 return that == this || (that instanceof IgnoreRightProcedure<?, ?>
074 && equals((IgnoreRightProcedure<?, ?>) that));
075 }
076
077 /**
078 * Learn whether another IgnoreRightProcedure is equal to this.
079 * @param that IgnoreRightProcedure to test
080 * @return boolean
081 */
082 public boolean equals(IgnoreRightProcedure<?, ?> that) {
083 return null != that && (null == procedure ? null == that.procedure : procedure.equals(that.procedure));
084 }
085
086 /**
087 * {@inheritDoc}
088 */
089 public int hashCode() {
090 int hash = "IgnoreRightProcedure".hashCode();
091 if (null != procedure) {
092 hash ^= procedure.hashCode();
093 }
094 return hash;
095 }
096
097 /**
098 * {@inheritDoc}
099 */
100 public String toString() {
101 return "IgnoreRightProcedure<" + procedure + ">";
102 }
103
104 /**
105 * Adapt a UnaryProcedure to the BinaryProcedure interface.
106 * @param <L> left type
107 * @param <R> right type
108 * @param procedure UnaryProcedure to adapt
109 * @return IgnoreRightProcedure
110 */
111 public static <L, R> IgnoreRightProcedure<L, R> adapt(UnaryProcedure<? super L> procedure) {
112 return null == procedure ? null : new IgnoreRightProcedure<L, R>(procedure);
113 }
114
115 }