小编Pus*_*pak的帖子

在多线程环境中，我正在 ConcurrentHashMap 实现上执行 get 和 put 操作。然而，结果却出乎意料。请找到下面的代码和输出。

import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

public class Test {

    private static final List<String> bars = Arrays.asList("1","2","3","4","5","6","7","8","9","10");
    private static final String KEY = UUID.randomUUID().toString();
    private static ExecutorService executorService = null;

    public static void main(String[] args) {
        for (int i = 1; i <= 20; i++) {
            executorService = Executors.newFixedThreadPool(2);
            Map<String, AtomicInteger> map = new ConcurrentHashMap<>();
            performMapOps(map);
            executorService.shutdown();
            try {
                while (!executorService.awaitTermination(1, …