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
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
/* __ *\
** ________ ___ / / ___ Scala API **
** / __/ __// _ | / / / _ | (c) 2002-2011, LAMP/EPFL **
** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ **
** /____/\___/_/ |_/____/_/ | | **
** |/ **
\* */
package scala.collection
package mutable
import scala.reflect.ArrayTag
import generic.CanBuildFrom
/**
* A class representing `Array[T]`.
*
* @tparam T type of the elements in this wrapped array.
*
* @author Martin Odersky, Stephane Micheloud
* @version 1.0
* @since 2.8
* @define Coll WrappedArray
* @define coll wrapped array
* @define orderDependent
* @define orderDependentFold
* @define mayNotTerminateInf
* @define willNotTerminateInf
*/
abstract sealed class FlatArray[T]
extends AbstractSeq[T]
with IndexedSeq[T]
with IndexedSeqOptimized[T, FlatArray[T]]
{
override protected[this] def thisCollection: FlatArray[T] = this
override protected[this] def toCollection(repr: FlatArray[T]): FlatArray[T] = repr
/** The length of the array */
def length: Int
/** The element at given index */
def apply(index: Int): T
/** Update element at given index */
def update(index: Int, elem: T): Unit
override def stringPrefix = "FlatArray"
override protected[this] def newBuilder: Builder[T, FlatArray[T]] = ??? // implemented in FlatArray.Impl
/** Clones this object, including the underlying Array. */
override def clone: FlatArray[T] = ??? // implemented in FlatArray.Impl
}
/** A companion object used to create instances of `WrappedArray`.
*/
object FlatArray {
def ofDim[Boxed, Unboxed](size:Int)
(implicit boxings: BoxingConversions[Boxed, Unboxed],
tag: ArrayTag[Unboxed]): FlatArray[Boxed] = {
val elems = Array.ofDim[Unboxed](size)
new FlatArray.Impl(elems, boxings, tag)
}
def empty[Boxed, Unboxed](implicit boxings: BoxingConversions[Boxed, Unboxed],
elemTag: ArrayTag[Unboxed]): FlatArray[Boxed] = apply()
def apply[Boxed, Unboxed](elems: Boxed*)
(implicit boxings: BoxingConversions[Boxed, Unboxed], elemTag: ArrayTag[Unboxed]): FlatArray[Boxed] = {
val b = newBuilder[Boxed, Unboxed]
b.sizeHint(elems.length)
b ++= elems
b.result
}
def newBuilder[Boxed, Unboxed]
(implicit boxings: BoxingConversions[Boxed, Unboxed], elemTag: ArrayTag[Unboxed]): Builder[Boxed, FlatArray[Boxed]] =
new Bldr[Boxed, Unboxed](boxings, elemTag)
implicit def canBuildFrom[Boxed, Unboxed](
implicit
boxings: BoxingConversions[Boxed, Unboxed],
elemTag: ArrayTag[Unboxed]): CanBuildFrom[FlatArray[_], Boxed, FlatArray[Boxed]] =
new CanBuildFrom[FlatArray[_], Boxed, FlatArray[Boxed]] {
def apply(from: FlatArray[_]): Builder[Boxed, FlatArray[Boxed]] =
newBuilder[Boxed, Unboxed]
def apply: Builder[Boxed, FlatArray[Boxed]] =
newBuilder[Boxed, Unboxed]
}
private class Bldr[Boxed, Unboxed](boxings: BoxingConversions[Boxed, Unboxed], tag: ArrayTag[Unboxed]) extends Builder[Boxed, FlatArray[Boxed]] {
private var elems: Array[Unboxed] = _
private var capacity: Int = 0
private var size: Int = 0
private def resize(size: Int) {
val newelems = tag.newArray(size)
if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size)
elems = newelems
capacity = size
}
override def sizeHint(size: Int) {
if (capacity < size) resize(size)
}
private def ensureSize(size: Int) {
if (capacity < size) {
var newsize = if (capacity == 0) 16 else capacity * 2
while (newsize < size) newsize *= 2
resize(newsize)
}
}
def +=(elem: Boxed): this.type = {
ensureSize(size + 1)
elems(size) = boxings.unbox(elem)
size += 1
this
}
def clear() {
size = 0
}
def result(): FlatArray[Boxed] = {
if (capacity == 0 || capacity != size) resize(size)
new FlatArray.Impl(elems, boxings, tag)
}
}
private class Impl[Boxed, Unboxed](
elems: Array[Unboxed],
boxings: BoxingConversions[Boxed, Unboxed],
elemTag: ArrayTag[Unboxed]) extends FlatArray[Boxed] {
def length = elems.length
def apply(idx: Int): Boxed = boxings.box(elems(idx))
def update(idx: Int, elem: Boxed) = elems(idx) = boxings.unbox(elem)
/** Creates new builder for this collection ==> move to subclasses
*/
override protected[this] def newBuilder: Builder[Boxed, FlatArray[Boxed]] =
new Bldr[Boxed, Unboxed](boxings, elemTag)
/** Clones this object, including the underlying Array. */
override def clone: FlatArray[Boxed] = new Impl[Boxed, Unboxed](elems.clone(), boxings, elemTag)
}
}
|
