blob: c8365f5cd073d8d489764fa10cf59d91740ea918 (
plain)
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
|
package com.pitchedapps.frost.utils
import java.io.Serializable
import kotlin.reflect.KProperty
/**
* Created by Allan Wang on 2017-05-30.
*
* Lazy delegate that can be invalidated if needed
* https://stackoverflow.com/a/37294840/4407321
*/
private object UNINITIALIZED
fun <T : Any> lazyResettable(initializer: () -> T): LazyResettable<T> = LazyResettable<T>(initializer)
class LazyResettable<T : Any>(private val initializer: () -> T, lock: Any? = null) : Lazy<T>, Serializable {
@Volatile private var _value: Any = UNINITIALIZED
private val lock = lock ?: this
fun invalidate() {
_value = UNINITIALIZED
}
override val value: T
get() {
val _v1 = _value
if (_v1 !== UNINITIALIZED)
@Suppress("UNCHECKED_CAST")
return _v1 as T
return synchronized(lock) {
val _v2 = _value
if (_v2 !== UNINITIALIZED) {
@Suppress("UNCHECKED_CAST")
_v2 as T
} else {
val typedValue = initializer()
_value = typedValue
typedValue
}
}
}
override fun isInitialized(): Boolean = _value !== UNINITIALIZED
override fun toString(): String = if (isInitialized()) value.toString() else "Lazy value not initialized yet."
operator fun setValue(any: Any, property: KProperty<*>, t: T) {
_value = t
}
}
|
