ConcurrentMap<String, String> map = new ConcurrentHashMap<>();
map.put("key", "value");
Lock lock = new ReentrantLock();
lock.lock();
try {
} finally {
lock.unlock();
}
ExecutorService executor = Executors.newFixedThreadPool(5);
executor.execute(() -> {
try {
} catch (Exception e) {
}
});
CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> {
});
future.exceptionally(ex -> {
return null;
});
CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> {
});
try {
} catch (TimeoutException e) {
}
