Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
PairWritable |
|
| 1.1428571428571428;1.143 |
1 | /* | |
2 | * Licensed to the Apache Software Foundation (ASF) under one | |
3 | * or more contributor license agreements. See the NOTICE file | |
4 | * distributed with this work for additional information | |
5 | * regarding copyright ownership. The ASF licenses this file | |
6 | * to you under the Apache License, Version 2.0 (the | |
7 | * "License"); you may not use this file except in compliance | |
8 | * with the License. You may obtain a copy of the License at | |
9 | * | |
10 | * http://www.apache.org/licenses/LICENSE-2.0 | |
11 | * | |
12 | * Unless required by applicable law or agreed to in writing, software | |
13 | * distributed under the License is distributed on an "AS IS" BASIS, | |
14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
15 | * See the License for the specific language governing permissions and | |
16 | * limitations under the License. | |
17 | */ | |
18 | package org.apache.giraph.writable.tuple; | |
19 | ||
20 | import java.io.DataInput; | |
21 | import java.io.DataOutput; | |
22 | import java.io.IOException; | |
23 | ||
24 | import org.apache.commons.lang3.tuple.Pair; | |
25 | import org.apache.hadoop.io.Writable; | |
26 | ||
27 | /** | |
28 | * Pair Writable class, that knows types upfront and can deserialize itself. | |
29 | * | |
30 | * PairWritable knows types, as instances are passed through constructor, and | |
31 | * are references are immutable (values themselves are mutable). | |
32 | * | |
33 | * Child classes specify no-arg constructor that passes concrete types in. | |
34 | * | |
35 | * Extends Pair, not ImmutablePair, since later class is final. Code is | |
36 | * copied from it. | |
37 | * | |
38 | * @param <L> Type of the left element | |
39 | * @param <R> Type of the right element | |
40 | */ | |
41 | 0 | public class PairWritable<L extends Writable, R extends Writable> |
42 | extends Pair<L, R> implements Writable { | |
43 | /** Left object */ | |
44 | private final L left; | |
45 | /** Right object */ | |
46 | private final R right; | |
47 | ||
48 | /** | |
49 | * Create a new pair instance. | |
50 | * | |
51 | * @param left the left value | |
52 | * @param right the right value | |
53 | */ | |
54 | 0 | public PairWritable(L left, R right) { |
55 | 0 | this.left = left; |
56 | 0 | this.right = right; |
57 | 0 | } |
58 | ||
59 | /** | |
60 | * <p> | |
61 | * Obtains an immutable pair of from two objects inferring | |
62 | * the generic types.</p> | |
63 | * | |
64 | * <p>This factory allows the pair to be created using inference to | |
65 | * obtain the generic types.</p> | |
66 | * | |
67 | * @param <L> the left element type | |
68 | * @param <R> the right element type | |
69 | * @param left the left element, may be null | |
70 | * @param right the right element, may be null | |
71 | * @return a pair formed from the two parameters, not null | |
72 | */ | |
73 | public static <L extends Writable, R extends Writable> | |
74 | PairWritable<L, R> of(L left, R right) { | |
75 | 0 | return new PairWritable<L, R>(left, right); |
76 | } | |
77 | ||
78 | @Override | |
79 | public final L getLeft() { | |
80 | 0 | return left; |
81 | } | |
82 | ||
83 | @Override | |
84 | public final R getRight() { | |
85 | 0 | return right; |
86 | } | |
87 | ||
88 | /** | |
89 | * <p>Throws {@code UnsupportedOperationException}.</p> | |
90 | * | |
91 | * <p>This pair is immutable, so this operation is not supported.</p> | |
92 | * | |
93 | * @param value the value to set | |
94 | * @return never | |
95 | * @throws UnsupportedOperationException as this operation is not supported | |
96 | */ | |
97 | @Override | |
98 | public final R setValue(R value) { | |
99 | 0 | throw new UnsupportedOperationException(); |
100 | } | |
101 | ||
102 | @Override | |
103 | public final void write(DataOutput out) throws IOException { | |
104 | 0 | left.write(out); |
105 | 0 | right.write(out); |
106 | 0 | } |
107 | ||
108 | @Override | |
109 | public final void readFields(DataInput in) throws IOException { | |
110 | 0 | left.readFields(in); |
111 | 0 | right.readFields(in); |
112 | 0 | } |
113 | } |