ocean.util.container.cache.model.containers.KeyToNode source code

1 /*******************************************************************************
2 
3     Mapping from key to the time-to-index mapping of an item in the cache.
4     Limits the number of available mappings to a fixed value and preallocates
5     all bucket elements in an array buffer.
6 
7     Copyright:
8         Copyright (c) 2009-2016 dunnhumby Germany GmbH.
9         All rights reserved.
10 
11     License:
12         Boost Software License Version 1.0. See LICENSE_BOOST.txt for details.
13         Alternatively, this file may be distributed under the terms of the Tango
14         3-Clause BSD License (see LICENSE_BSD.txt for details).
15 
16 *******************************************************************************/
17 
18 module ocean.util.container.cache.model.containers.KeyToNode;
19 
20 
21 import ocean.util.container.map.HashMap;
22 import ocean.util.container.map.model.BucketElementFreeList;
23 import ocean.util.container.cache.model.containers.ArrayPool;
24 import ocean.util.container.cache.model.containers.TimeToIndex;
25 
26 /******************************************************************************/
27 
28 class KeyToNode: HashMap!(TimeToIndex.Node*)
29 {
30     static class ArrayAllocatedFreeBucketElements: BucketElementFreeList!(Bucket.Element)
31     {
32         /***********************************************************************
33 
34             Preallocated pool of bucket elements.
35 
36         ***********************************************************************/
37 
38         private GenericArrayPool pool;
39 
40         /***********************************************************************
41 
42             Constructor.
43 
44             Params:
45                 n = number of elements in the pool
46 
47         ***********************************************************************/
48 
49         private this ( size_t n )
50         {
51             this.pool = new GenericArrayPool(n, Bucket.Element.sizeof);
52         }
53 
54         /***********************************************************************
55 
56             Obtains a new element from the pool.
57 
58             Returns:
59                 A new pool element.
60 
61         ***********************************************************************/
62 
63         protected override Bucket.Element* newElement ( )
64         {
65             return cast(Bucket.Element*)this.pool.next;
66         }
67     }
68 
69     /***************************************************************************
70 
71         Bucket elements allocator.
72         The elements are allocated only during container construction,
73         and never freed.
74 
75     ***************************************************************************/
76 
77     private ArrayAllocatedFreeBucketElements allocator;
78 
79     /***********************************************************************
80 
81         Constructor.
82 
83         Params:
84             n = maximum number of elements in mapping
85 
86     ***********************************************************************/
87 
88     public this ( size_t n )
89     {
90         this.allocator = new ArrayAllocatedFreeBucketElements(n);
91         super(this.allocator, n);
92     }
93 }
94 
95 unittest
96 {
97     KeyToNode map = new KeyToNode(5);
98     (*map.put(1)) = new TimeToIndex.Node();
99     (*map.put(2)) = new TimeToIndex.Node();
100     (*map.put(3)) = new TimeToIndex.Node();
101     (*map.put(4)) = new TimeToIndex.Node();
102     (*map.put(5)) = new TimeToIndex.Node();
103     map.clear();
104     map.clear();
105     map.clear();
106 }
107 
108 unittest
109 {
110     KeyToNode map = new KeyToNode(100000);
111     map.clear();
112     map.put(9207674216414740734);
113     map.put(8595442437537477107);
114     map.clear();
115     map.put(8595442437537477107);
116     map.clear();
117     map.put(9207674216414740734);
118     map.put(8595442437537477106);
119     map.put(8595442437537477108);
120     map.put(8595442437537477110);
121     map.put(8595442437537477112);
122     map.clear();
123 }