forked from mtumilowicz/java11-lambda-patterns
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathCustomer.java
More file actions
76 lines (64 loc) · 1.97 KB
/
Customer.java
File metadata and controls
76 lines (64 loc) · 1.97 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
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
package customer;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import converters.ListToTripleConverter;
import lombok.Builder;
import lombok.Value;
import org.apache.commons.collections4.ListUtils;
import org.apache.commons.collections4.SetUtils;
import org.apache.commons.lang3.tuple.Triple;
import java.math.BigDecimal;
import java.time.Year;
import java.util.Optional;
import java.util.Set;
import java.util.stream.Stream;
import static java.util.Comparator.comparing;
import static java.util.Comparator.reverseOrder;
import static java.util.Objects.nonNull;
import static java.util.stream.Collectors.*;
/**
* Created by mtumilowicz on 2018-11-24.
*/
@Value
@Builder
public class Customer {
ImmutableList<Order> orders;
ImmutableList<Expense> expenses;
Optional<Order> findOrderWithMaxPrice() {
return ListUtils.emptyIfNull(orders).stream()
.filter(Order::hasPrice)
.max(comparing(Order::getPrice));
}
Triple<Order, Order, Order> findTop3OrdersByPrice() {
return ListUtils.emptyIfNull(orders).stream()
.filter(Order::hasPrice)
.sorted(comparing(Order::getPrice, reverseOrder()))
.limit(3)
.collect(collectingAndThen(toList(), ListToTripleConverter::convert));
}
ImmutableMap<Year, Set<String>> yearTagsExpensesMap() {
return ListUtils.emptyIfNull(expenses).stream()
.collect(collectingAndThen(groupingBy(Expense::getYear, flatMapping(Expense::getTagsStream, toSet())),
ImmutableMap::copyOf)
);
}
}
@Value
@Builder
class Expense {
Year year;
ImmutableSet<String> tags;
Stream<String> getTagsStream() {
return SetUtils.emptyIfNull(tags).stream();
}
}
@Value
@Builder
class Order {
int id;
BigDecimal price;
boolean hasPrice() {
return nonNull(price);
}
}