1、測試異步調用：

static void testCompletableFuture1() throws ExecutionException, InterruptedException {// 1、無返回值的異步任務。異步線程執行RunnableCompletableFuture.runAsync(() -> System.out.println("only you"));// 2、有返回值的異步任務。執行Supplier函數并返回結果CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> "3個時辰內必須找人解毒，不過老夫也可以幫忙哦");System.out.println("supplyAsync, result: " + future.get()); // 阻塞獲取結果}

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2、鏈式調用：

static void testCompletableFuture2() throws ExecutionException, InterruptedException {System.out.println("main thread, id: " +  Thread.currentThread().getId());// 鏈式操作CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> {System.out.println("supplyAsync thread: " + Thread.currentThread().getId());return "我行我素";});// 結果轉換future = future.thenApply(s -> {System.out.println("thenApply thread: " + Thread.currentThread().getId());return s + " !!!";});// 結果消費CompletableFuture<Void> future2 = future.thenAccept(s -> {System.out.println("thenAccept thread: " + Thread.currentThread().getId());System.out.println(s);// 輸出結果});}

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3、依賴其他Future任務

// thenCompose()串聯多個異步任務,前一個任務結果為后一個任務的輸入static void testCompletableFuture3() throws ExecutionException, InterruptedException {CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> "haiyangxuanfeng");future = future.thenCompose(s -> CompletableFuture.supplyAsync(s::toUpperCase));future.thenAccept(new Consumer<String>() {@Overridepublic void accept(String s) {System.out.println(s);}}).get();}

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