1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
//
// ListPartitioner.cs
//
// Author:
// Jérémie "Garuma" Laval <jeremie.laval@gmail.com>
//
// Copyright (c) 2009 Jérémie "Garuma" Laval
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#if NET_4_0
using System;
using System.Threading;
using System.Collections.Generic;
using System.Runtime.InteropServices;
namespace System.Collections.Concurrent.Partitioners
{
// Represent a Range partitioner
internal class ListPartitioner<T> : OrderablePartitioner<T>
{
IList<T> source;
public ListPartitioner (IList<T> source) : base (true, true, true)
{
this.source = source;
}
public override IList<IEnumerator<KeyValuePair<long, T>>> GetOrderablePartitions (int partitionCount)
{
if (partitionCount <= 0)
throw new ArgumentOutOfRangeException ("partitionCount");
IEnumerator<KeyValuePair<long, T>>[] enumerators
= new IEnumerator<KeyValuePair<long, T>>[partitionCount];
int count = source.Count / partitionCount;
int extra = 0;
if (source.Count < partitionCount) {
count = 1;
} else {
extra = source.Count % partitionCount;
if (extra > 0)
++count;
}
int currentIndex = 0;
Range[] ranges = new Range[enumerators.Length];
for (int i = 0; i < ranges.Length; i++) {
ranges[i] = new Range (currentIndex,
currentIndex + count);
currentIndex += count;
if (--extra == 0)
--count;
}
for (int i = 0; i < enumerators.Length; i++) {
enumerators[i] = GetEnumeratorForRange (ranges, i);
}
return enumerators;
}
class Range
{
public int Actual;
public readonly int LastIndex;
public Range (int frm, int lastIndex)
{
Actual = frm;
LastIndex = lastIndex;
}
}
IEnumerator<KeyValuePair<long, T>> GetEnumeratorForRange (Range[] ranges, int workerIndex)
{
if (ranges[workerIndex].Actual >= source.Count)
return GetEmpty ();
return GetEnumeratorForRangeInternal (ranges, workerIndex);
}
IEnumerator<KeyValuePair<long, T>> GetEmpty ()
{
yield break;
}
IEnumerator<KeyValuePair<long, T>> GetEnumeratorForRangeInternal (Range[] ranges, int workerIndex)
{
Range range = ranges[workerIndex];
int lastIndex = range.LastIndex;
int index = range.Actual;
for (int i = index; i < lastIndex; i = ++range.Actual) {
yield return new KeyValuePair<long, T> (i, source[i]);
}
}
}
}
#endif
|
