-
Notifications
You must be signed in to change notification settings - Fork 1.2k
Expand file tree
/
Copy pathFillMap.java
More file actions
38 lines (37 loc) · 1.13 KB
/
FillMap.java
File metadata and controls
38 lines (37 loc) · 1.13 KB
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
// onjava/FillMap.java
// (c)2021 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
package onjava;
import java.util.*;
import java.util.function.*;
import java.util.stream.*;
public class FillMap {
public static <K, V> Map<K,V>
basic(Supplier<Pair<K,V>> pairGen, int size) {
return Stream.generate(pairGen)
.limit(size)
.collect(Collectors
.toMap(Pair::key, Pair::value));
}
public static <K, V> Map<K,V>
basic(Supplier<K> keyGen,
Supplier<V> valueGen, int size) {
return Stream.generate(
() -> Pair.make(keyGen.get(), valueGen.get()))
.limit(size)
.collect(Collectors
.toMap(Pair::key, Pair::value));
}
public static <K, V, M extends Map<K,V>>
M create(Supplier<K> keyGen,
Supplier<V> valueGen,
Supplier<M> mapSupplier, int size) {
return Stream.generate( () ->
Pair.make(keyGen.get(), valueGen.get()))
.limit(size)
.collect(Collectors
.toMap(Pair::key, Pair::value,
(k, v) -> k, mapSupplier));
}
}