Coverage Report - org.apache.commons.functor.adapter.BinaryPredicateBinaryFunction
 
Classes in this File Line Coverage Branch Coverage Complexity
BinaryPredicateBinaryFunction
100%
13/13
70%
14/20
2
 
 1  
 /*
 2  
  * Licensed to the Apache Software Foundation (ASF) under one or more
 3  
  * contributor license agreements.  See the NOTICE file distributed with
 4  
  * this work for additional information regarding copyright ownership.
 5  
  * The ASF licenses this file to You under the Apache License, Version 2.0
 6  
  * (the "License"); you may not use this file except in compliance with
 7  
  * the License.  You may obtain a copy of the License at
 8  
  *
 9  
  *      http://www.apache.org/licenses/LICENSE-2.0
 10  
  *
 11  
  * Unless required by applicable law or agreed to in writing, software
 12  
  * distributed under the License is distributed on an "AS IS" BASIS,
 13  
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 14  
  * See the License for the specific language governing permissions and
 15  
  * limitations under the License.
 16  
  */
 17  
 package org.apache.commons.functor.adapter;
 18  
 
 19  
 import java.io.Serializable;
 20  
 
 21  
 import org.apache.commons.functor.BinaryFunction;
 22  
 import org.apache.commons.functor.BinaryPredicate;
 23  
 
 24  
 /**
 25  
  * Adapts a
 26  
  * {@link BinaryPredicate BinaryPredicate}
 27  
  * to the
 28  
  * {@link BinaryFunction BinaryFunction} interface.
 29  
  * <p/>
 30  
  * Note that although this class implements
 31  
  * {@link Serializable}, a given instance will
 32  
  * only be truly <code>Serializable</code> if the
 33  
  * underlying predicate is.  Attempts to serialize
 34  
  * an instance whose delegate is not
 35  
  * <code>Serializable</code> will result in an exception.
 36  
  *
 37  
  * @param <L> the left argument type.
 38  
  * @param <R> the right argument type.
 39  
  * @version $Revision: 1156767 $ $Date: 2011-08-11 21:38:12 +0200 (Thu, 11 Aug 2011) $
 40  
  * @author Rodney Waldhoff
 41  
  */
 42  8
 public final class BinaryPredicateBinaryFunction<L, R> implements BinaryFunction<L, R, Boolean>, Serializable {
 43  
     /**
 44  
      * serialVersionUID declaration.
 45  
      */
 46  
     private static final long serialVersionUID = 207209665276797678L;
 47  
     /** The {@link BinaryPredicate BinaryPredicate} I'm wrapping. */
 48  
     private final BinaryPredicate<? super L, ? super R> predicate;
 49  
 
 50  
     /**
 51  
      * Create a new BinaryPredicateBinaryFunction.
 52  
      * @param predicate to adapt
 53  
      */
 54  38
     public BinaryPredicateBinaryFunction(BinaryPredicate<? super L, ? super R> predicate) {
 55  38
         this.predicate = predicate;
 56  38
     }
 57  
 
 58  
     /**
 59  
      * {@inheritDoc}
 60  
      * Returns <code>Boolean.TRUE</code> (<code>Boolean.FALSE</code>)
 61  
      * when the {@link BinaryPredicate#test test} method of my underlying
 62  
      * predicate returns <code>true</code> (<code>false</code>).
 63  
      *
 64  
      * @return a non-<code>null</code> <code>Boolean</code> instance
 65  
      */
 66  
     public Boolean evaluate(L left, R right) {
 67  8
         return predicate.test(left, right) ? Boolean.TRUE : Boolean.FALSE;
 68  
     }
 69  
 
 70  
     /**
 71  
      * {@inheritDoc}
 72  
      */
 73  
     public boolean equals(Object that) {
 74  34
         return that == this
 75  
                 || (that instanceof BinaryPredicateBinaryFunction<?, ?>
 76  
                 && equals((BinaryPredicateBinaryFunction<?, ?>) that));
 77  
     }
 78  
 
 79  
     /**
 80  
      * Learn whether another BinaryPredicateBinaryFunction is equal to this.
 81  
      * @param that BinaryPredicateBinaryFunction to test
 82  
      * @return boolean
 83  
      */
 84  
     public boolean equals(BinaryPredicateBinaryFunction<?, ?> that) {
 85  26
         return null != that && (null == predicate ? null == that.predicate : predicate.equals(that.predicate));
 86  
     }
 87  
 
 88  
     /**
 89  
      * {@inheritDoc}
 90  
      */
 91  
     public int hashCode() {
 92  44
         int hash = "BinaryPredicateBinaryFunction".hashCode();
 93  44
         if (null != predicate) {
 94  44
             hash ^= predicate.hashCode();
 95  
         }
 96  44
         return hash;
 97  
     }
 98  
 
 99  
     /**
 100  
      * {@inheritDoc}
 101  
      */
 102  
     public String toString() {
 103  32
         return "BinaryPredicateBinaryFunction<" + predicate + ">";
 104  
     }
 105  
 
 106  
     /**
 107  
      * Adapt the given, possibly-<code>null</code>,
 108  
      * {@link BinaryPredicate BinaryPredicate} to the
 109  
      * {@link BinaryFunction BinaryFunction} interface.
 110  
      * When the given <code>BinaryPredicate</code> is <code>null</code>,
 111  
      * returns <code>null</code>.
 112  
      *
 113  
      * @param <L> left type
 114  
      * @param <R> right type
 115  
      * @param predicate the possibly-<code>null</code>
 116  
      *        {@link BinaryPredicate BinaryPredicate} to adapt
 117  
      * @return a <code>BinaryPredicateBinaryFunction</code> wrapping the given
 118  
      *         {@link BinaryPredicate BinaryPredicate}, or <code>null</code>
 119  
      *         if the given <code>BinaryPredicate</code> is <code>null</code>
 120  
      */
 121  
     public static <L, R> BinaryPredicateBinaryFunction<L, R> adapt(BinaryPredicate<? super L, ? super R> predicate) {
 122  20
         return null == predicate ? null : new BinaryPredicateBinaryFunction<L, R>(predicate);
 123  
     }
 124  
 
 125  
 }