Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
NaryExpression |
|
| 1.25;1.25 |
1 | /* | |
2 | * #%L | |
3 | * NaryExpression.java - mongodb-async-driver - Allanbank Consulting, Inc. | |
4 | * %% | |
5 | * Copyright (C) 2011 - 2014 Allanbank Consulting, Inc. | |
6 | * %% | |
7 | * Licensed under the Apache License, Version 2.0 (the "License"); | |
8 | * you may not use this file except in compliance with the License. | |
9 | * You may obtain a copy of the License at | |
10 | * | |
11 | * http://www.apache.org/licenses/LICENSE-2.0 | |
12 | * | |
13 | * Unless required by applicable law or agreed to in writing, software | |
14 | * distributed under the License is distributed on an "AS IS" BASIS, | |
15 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
16 | * See the License for the specific language governing permissions and | |
17 | * limitations under the License. | |
18 | * #L% | |
19 | */ | |
20 | package com.allanbank.mongodb.builder.expression; | |
21 | ||
22 | import java.io.StringWriter; | |
23 | import java.util.ArrayList; | |
24 | import java.util.List; | |
25 | ||
26 | import com.allanbank.mongodb.bson.Element; | |
27 | import com.allanbank.mongodb.bson.ElementAssignable; | |
28 | import com.allanbank.mongodb.bson.element.ArrayElement; | |
29 | import com.allanbank.mongodb.bson.element.DocumentElement; | |
30 | import com.allanbank.mongodb.bson.element.JsonSerializationVisitor; | |
31 | ||
32 | /** | |
33 | * NaryExpression provides an implementation of an {@link Expression} with 2-N | |
34 | * operands. | |
35 | * | |
36 | * @api.no This class is <b>NOT</b> part of the drivers API. This class may be | |
37 | * mutated in incompatible ways between any two releases of the driver. | |
38 | * @copyright 2012-2013, Allanbank Consulting, Inc., All Rights Reserved | |
39 | */ | |
40 | 7 | public class NaryExpression implements Expression, ElementAssignable { |
41 | ||
42 | /** The expression expressed as an {@link ArrayElement}. */ | |
43 | protected final ArrayElement myExpressions; | |
44 | ||
45 | /** | |
46 | * Creates a new NaryExpression. | |
47 | * | |
48 | * @param operator | |
49 | * The operator this object represents. | |
50 | * @param expressions | |
51 | * The sub expressions. | |
52 | */ | |
53 | public NaryExpression(final String operator, | |
54 | 32 | final Expression... expressions) { |
55 | 32 | final List<Element> elements = new ArrayList<Element>( |
56 | expressions.length); | |
57 | 102 | for (int i = 0; i < expressions.length; ++i) { |
58 | 70 | elements.add(expressions[i].toElement(String.valueOf(i))); |
59 | } | |
60 | ||
61 | 32 | myExpressions = new ArrayElement(operator, elements); |
62 | 32 | } |
63 | ||
64 | /** | |
65 | * {@inheritDoc} | |
66 | * <p> | |
67 | * Overridden to return the sub expressions as a {@link ArrayElement}: | |
68 | * </p> | |
69 | * <blockquote> | |
70 | * | |
71 | * <pre> | |
72 | * <code> | |
73 | * "$op" : [ <e1>, <e2>, <e2>, ... ] | |
74 | * </code> | |
75 | * </pre> | |
76 | * | |
77 | * </blockquote> | |
78 | */ | |
79 | @Override | |
80 | public ArrayElement asElement() { | |
81 | 19 | return myExpressions; |
82 | } | |
83 | ||
84 | /** | |
85 | * {@inheritDoc} | |
86 | * <p> | |
87 | * Overridden to return the sub expressions as a document with a nested | |
88 | * array element: | |
89 | * </p> | |
90 | * <blockquote> | |
91 | * | |
92 | * <pre> | |
93 | * <code> | |
94 | * { <name> : { "$op" : [ <e1>, <e2>, <e2>, ... ] } } | |
95 | * </code> | |
96 | * </pre> | |
97 | * | |
98 | * </blockquote> | |
99 | */ | |
100 | @Override | |
101 | public DocumentElement toElement(final String name) { | |
102 | 32 | return new DocumentElement(name, myExpressions); |
103 | } | |
104 | ||
105 | /** | |
106 | * {@inheritDoc} | |
107 | * <p> | |
108 | * Overridden to return the expression in JSON format. | |
109 | * </p> | |
110 | * <blockquote> | |
111 | * | |
112 | * <pre> | |
113 | * <code> | |
114 | * "$op" : [ <e1>, <e2>, <e2>, ... ] | |
115 | * </code> | |
116 | * </pre> | |
117 | * | |
118 | * </blockquote> | |
119 | */ | |
120 | @Override | |
121 | public String toString() { | |
122 | 1 | final StringWriter sink = new StringWriter(); |
123 | 1 | final JsonSerializationVisitor json = new JsonSerializationVisitor( |
124 | sink, true); | |
125 | ||
126 | 1 | myExpressions.accept(json); |
127 | ||
128 | 1 | return sink.toString(); |
129 | } | |
130 | } |