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 org.zwobble.mammoth.internal.util;
import java.util.Optional;
import java.util.OptionalInt;
import java.util.function.BiFunction;
import java.util.function.IntFunction;
public class Optionals {
public static <T> Optional<T> first(Optional<T> first, Optional<T> second) {
if (first.isPresent()) {
return first;
} else {
return second;
}
}
public static <T1, T2, R> Optional<R> flatMap(
Optional<T1> first,
Optional<T2> second,
BiFunction<T1, T2, Optional<R>> function)
{
if (first.isPresent() && second.isPresent()) {
return function.apply(first.get(), second.get());
} else {
return Optional.empty();
}
}
public static <T1, T2, R> Optional<R> map(
Optional<T1> first,
Optional<T2> second,
BiFunction<T1, T2, R> function)
{
if (first.isPresent() && second.isPresent()) {
return Optional.of(function.apply(first.get(), second.get()));
} else {
return Optional.empty();
}
}
public static <R> Optional<R> map(
OptionalInt first,
IntFunction<R> function)
{
if (first.isPresent()) {
return Optional.of(function.apply(first.getAsInt()));
} else {
return Optional.empty();
}
}
}
|
