package org.java.learn.collection;
import java.util.*;
public class ARemoveBListExample {
public static void main(String[] args) {
Set<String> aSet = new HashSet<>();
Set<String> bSet = new HashSet<>();
for (int i = 0; i < 10000; i++) {
String str = UUID.randomUUID().toString();
aSet.add(str);
bSet.add(str);
}
for (int i = 0; i < 10000000; i++) {
aSet.add(UUID.randomUUID().toString());
}
//求A集合到B集合的差
long start = System.currentTimeMillis();
// List<String> result = aSet.parallelStream().filter(a -> !bSet.contains(a)).collect(Collectors.toList());
aSet.removeIf(a -> bSet.contains(a));
long end = System.currentTimeMillis(); System.out.println("cost: " + (end-start) + "ms, result size:" + aSet.size());
}
}