aermicioi.aedi.storage.aggregate

1 /**
2 
3 License:
4 	Boost Software License - Version 1.0 - August 17th, 2003
5     
6     Permission is hereby granted, free of charge, to any person or organization
7     obtaining a copy of the software and accompanying documentation covered by
8     this license (the "Software") to use, reproduce, display, distribute,
9     execute, and transmit the Software, and to prepare derivative works of the
10     Software, and to permit third-parties to whom the Software is furnished to
11     do so, all subject to the following:
12     
13     The copyright notices in the Software and this entire statement, including
14     the above license grant, this restriction and the following disclaimer,
15     must be included in all copies of the Software, in whole or in part, and
16     all derivative works of the Software, unless such copies or derivative
17     works are solely in the form of machine-executable object code generated by
18     a source language processor.
19     
20     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21     IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22     FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
23     SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
24     FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
25     ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26     DEALINGS IN THE SOFTWARE.
27 
28 Authors:
29 	Alexandru Ermicioi
30 **/
31 module aermicioi.aedi.storage.aggregate_locator;
32 
33 import aermicioi.aedi.storage.locator;
34 import aermicioi.aedi.exception.not_found_exception;
35 import std.conv : to;
36 import std.range.interfaces;
37 import std.typecons;
38 
39 /**
40 An implementation of AggregateLocator.
41 **/
42 class AggregateLocatorImpl(Type = Object, KeyType = string, LocatorKeyType = KeyType) : MutableAggregateLocator!(Type, KeyType, LocatorKeyType) {
43     
44     protected {
45         
46         Locator!(Type, KeyType)[LocatorKeyType] locators;
47     }
48     
49     public {
50         
51         /**
52         Add a Locator by key.
53         
54         Params:
55         	key = key by which to identify the locator.
56         	locator = the Locator that will be added to AggregateLocator
57         **/
58         AggregateLocatorImpl!(Type, KeyType, LocatorKeyType) set(Locator!(Type, KeyType) locator, LocatorKeyType key) {
59             
60             this.locators[key] = locator;
61             
62             return this;
63         }
64         
65         /**
66         Removes a Locator by key.
67         
68         Params:
69         	key = the identity of locator that should be removed.
70         **/
71         AggregateLocatorImpl!(Type, KeyType, LocatorKeyType) remove(LocatorKeyType key) {
72             
73             this.locators.remove(key);
74             
75             return this;
76         }
77         
78         /**
79 		Get an Type that is associated with key.
80 		
81 		Params:
82 			identity = the element id.
83 			
84 		Throws:
85 			NotFoundException in case if the element wasn't found.
86 		
87 		Returns:
88 			Type element if it is available.
89 		**/
90         Type get(KeyType identity) {
91             
92             foreach (locator; this.locators) {
93                 
94                 if (locator.has(identity)) {
95                     return locator.get(identity);
96                 }
97             }
98             
99             import std.traits;
100             
101             if ((identity in this.locators) !is null) {
102                 auto result = cast(Type) this.locators[identity];
103                 
104                 if (result !is null) {
105                     return result;
106                 }
107             }
108             
109             throw new NotFoundException("Could not find an object with " ~ identity.to!string ~ " identity.");
110         }
111         
112         /**
113         Check if an element is present in Locator by key id.
114         
115         Note:
116         	This check should be done for elements that locator actually contains, and
117         	not in chained locator (when locator is also a DelegatingLocator) for example.
118         Params:
119         	identity = identity of element.
120         	
121     	Returns:
122     		bool true if an element by key is present in Locator.
123         **/
124         bool has(in KeyType identity) inout {
125             
126             if ((identity in this.locators) !is null) {
127                 return true;
128             }
129             
130             foreach (locator; this.locators) {
131                 
132                 if (locator.has(identity)) {
133                     return true;
134                 }
135             }
136             
137             return false;
138         }
139         
140         /**
141         Get a specific locator.
142         
143         Params:
144             key = the locator identity.
145         **/
146         Locator!(Type, KeyType) getLocator(LocatorKeyType key) {
147             
148             if (this.hasLocator(key)) {
149                 return this.locators[key];
150             }
151             
152             throw new NotFoundException("Could not find any locator with identity of " ~ key);
153         }
154         
155         /**
156         Get all locators in aggregate locator
157         
158         Returns:
159         	InputRange!(Tuple!(Locator!(Type, KeyType), LocatorKeyType)) a range of locator => identity
160         **/
161         InputRange!(Tuple!(Locator!(Type, KeyType), LocatorKeyType)) getLocators() {
162             import std.algorithm;
163             
164             return this.locators.byKeyValue.map!(
165                 a => tuple(a.value, a.key)
166             ).inputRangeObject;
167         }
168         
169         /**
170         Check if aggregate locator contains a specific locator.
171         
172         Params:
173         	key = the identity of locator in aggregate locator
174         **/
175         bool hasLocator(LocatorKeyType key) inout {
176             
177             return (key in this.locators) !is null;
178         }
179     }
180 }