70 lines
2.1 KiB
Java
70 lines
2.1 KiB
Java
// collectionsindepth/SetPerformance.java
|
|
// (c)2016 MindView LLC: see Copyright.txt
|
|
// We make no guarantees that this code is fit for any purpose.
|
|
// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
|
|
// Demonstrates performance differences in Sets
|
|
// {Args: 100 5000} Small to keep build testing short
|
|
import java.util.*;
|
|
|
|
public class SetPerformance {
|
|
static List<Test<Set<Integer>>> tests =
|
|
new ArrayList<>();
|
|
static {
|
|
tests.add(new Test<Set<Integer>>("add") {
|
|
@Override
|
|
int test(Set<Integer> set, TestParam tp) {
|
|
int loops = tp.loops;
|
|
int size = tp.size;
|
|
for(int i = 0; i < loops; i++) {
|
|
set.clear();
|
|
for(int j = 0; j < size; j++)
|
|
set.add(j);
|
|
}
|
|
return loops * size;
|
|
}
|
|
});
|
|
tests.add(new Test<Set<Integer>>("contains") {
|
|
@Override
|
|
int test(Set<Integer> set, TestParam tp) {
|
|
int loops = tp.loops;
|
|
int span = tp.size * 2;
|
|
for(int i = 0; i < loops; i++)
|
|
for(int j = 0; j < span; j++)
|
|
set.contains(j);
|
|
return loops * span;
|
|
}
|
|
});
|
|
tests.add(new Test<Set<Integer>>("iterate") {
|
|
@Override
|
|
int test(Set<Integer> set, TestParam tp) {
|
|
int loops = tp.loops * 10;
|
|
for(int i = 0; i < loops; i++) {
|
|
Iterator<Integer> it = set.iterator();
|
|
while(it.hasNext())
|
|
it.next();
|
|
}
|
|
return loops * set.size();
|
|
}
|
|
});
|
|
}
|
|
public static void main(String[] args) {
|
|
if(args.length > 0)
|
|
Tester.defaultParams = TestParam.array(args);
|
|
Tester.fieldWidth = 10;
|
|
Tester.run(new TreeSet<>(), tests);
|
|
Tester.run(new HashSet<>(), tests);
|
|
Tester.run(new LinkedHashSet<>(), tests);
|
|
}
|
|
}
|
|
/* Output:
|
|
------------- TreeSet -------------
|
|
size add contains iterate
|
|
100 85 51 9
|
|
------------- HashSet -------------
|
|
size add contains iterate
|
|
100 27 12 12
|
|
---------- LinkedHashSet ----------
|
|
size add contains iterate
|
|
100 28 10 7
|
|
*/
|