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 
18 package org.apache.commons.math3.fraction;
19 
20 import java.io.Serializable;
21 
22 import org.apache.commons.math3.Field;
23 import org.apache.commons.math3.FieldElement;
24 
25 /**
26  * Representation of the fractional numbers  without any overflow field.
27  * <p>
28  * This class is a singleton.
29  * </p>
30  * @see Fraction
31  * @since 2.0
32  */
33 public class BigFractionField implements Field<BigFraction>, Serializable  {
34 
35     /** Serializable version identifier */
36     private static final long serialVersionUID = -1699294557189741703L;
37 
38     /** Private constructor for the singleton.
39      */
BigFractionField()40     private BigFractionField() {
41     }
42 
43     /** Get the unique instance.
44      * @return the unique instance
45      */
getInstance()46     public static BigFractionField getInstance() {
47         return LazyHolder.INSTANCE;
48     }
49 
50     /** {@inheritDoc} */
getOne()51     public BigFraction getOne() {
52         return BigFraction.ONE;
53     }
54 
55     /** {@inheritDoc} */
getZero()56     public BigFraction getZero() {
57         return BigFraction.ZERO;
58     }
59 
60     /** {@inheritDoc} */
getRuntimeClass()61     public Class<? extends FieldElement<BigFraction>> getRuntimeClass() {
62         return BigFraction.class;
63     }
64     // CHECKSTYLE: stop HideUtilityClassConstructor
65     /** Holder for the instance.
66      * <p>We use here the Initialization On Demand Holder Idiom.</p>
67      */
68     private static class LazyHolder {
69         /** Cached field instance. */
70         private static final BigFractionField INSTANCE = new BigFractionField();
71     }
72     // CHECKSTYLE: resume HideUtilityClassConstructor
73 
74     /** Handle deserialization of the singleton.
75      * @return the singleton instance
76      */
readResolve()77     private Object readResolve() {
78         // return the singleton instance
79         return LazyHolder.INSTANCE;
80     }
81 
82 }
83