CompletableFuture是java8提供的异步任务创建,回调,编排和异常处理.

示例

ExecutorService executor = Executors.newFixedThreadPool(5);CommonUtil.printThreadLog("start");CompletableFuture future = CompletableFuture.supplyAsync(() -> {CommonUtil.printThreadLog("读取文件");String news = CommonUtil.readFile("news.txt");CommonUtil.printThreadLog("读取文件结束");return news;},executor);CommonUtil.printThreadLog(future.get());//关闭线程池executor.shutdown();CommonUtil.printThreadLog("end");

示例中使用到的CommonUtil

public class CommonUtil {/*** 读取指定路径的文件* @param pathFile* @return*/public static String readFile(String pathFile){try {pathFile = "D:\\study\\zlm_platform\\src\\main\\resources\\"+pathFile;return Files.readString(Paths.get(pathFile));} catch (IOException e) {e.printStackTrace();return "";}}/*** 休眠指定毫秒数* @param millis*/public static void sleepMillis(long millis){try {TimeUnit.MILLISECONDS.sleep(millis);} catch (InterruptedException e) {e.printStackTrace();}}/*** 休眠指定秒数* @param seconds*/public static void sleepSecond(int seconds){try {TimeUnit.SECONDS.sleep(seconds);} catch (InterruptedException e) {e.printStackTrace();}}/*** 答应输出带线程信息的日志* @param message*/public static void printThreadLog(String message){String result = new StringJoiner(" | ").add(String.valueOf(System.currentTimeMillis())).add(String.format("%2d",Thread.currentThread().getId())).add(String.valueOf(Thread.currentThread().getName())).add(message).toString();System.out.println(result);}}