Java CompletableFuture组合拼装异步线程任务
private void seq() throws ExecutionException, InterruptedException {
System.out.println("时间1:" + System.currentTimeMillis());
CompletableFuture<String> f1 = CompletableFuture.supplyAsync(new Supplier<String>() {
@Override
public String get() {
try {
TimeUnit.SECONDS.sleep(3);
} catch (InterruptedException e) {
e.printStackTrace();
}
return "2018";
}
});
System.out.println("时间2:" + System.currentTimeMillis());
CompletableFuture<Integer> f2 = f1.thenApply(new Function<String, Integer>() {
@Override
public Integer apply(String s) {
try {
TimeUnit.SECONDS.sleep(3);
} catch (InterruptedException e) {
e.printStackTrace();
}
return Integer.parseInt(s);
}
});
System.out.println("时间3:" + System.currentTimeMillis());
CompletableFuture<Double> f3 = f2.thenApply(new Function<Integer, Double>() {
@Override
public Double apply(Integer i) {
try {
TimeUnit.SECONDS.sleep(3);
} catch (InterruptedException e) {
e.printStackTrace();
}
return (double) i;
}
});
System.out.println("时间4:" + System.currentTimeMillis());
f3.whenComplete((v, a) -> {
System.out.println("v: " + v);
System.out.println("a: " + a);
});
System.out.println("时间5:" + System.currentTimeMillis());
System.out.println(f3.get());
System.out.println("时间6:" + System.currentTimeMillis());
}
输出结果:
06-12 18:49:08.337 6047-6047/zhangphil.test I/System.out: 时间1:1528800548337
06-12 18:49:08.339 6047-6047/zhangphil.test I/System.out: 时间2:1528800548339
06-12 18:49:08.340 6047-6047/zhangphil.test I/System.out: 时间3:1528800548340
06-12 18:49:08.341 6047-6047/zhangphil.test I/System.out: 时间4:1528800548341
06-12 18:49:08.342 6047-6047/zhangphil.test I/System.out: 时间5:1528800548342
06-12 18:49:17.347 6047-6089/zhangphil.test I/System.out: v: 2018.0
a: null
06-12 18:49:17.347 6047-6047/zhangphil.test I/System.out: 2018.0
06-12 18:49:17.348 6047-6047/zhangphil.test I/System.out: 时间6:1528800557348