多线程之CompletableFuture（下）

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thenAcceptBothAsync

thenAcceptBothAsync(CompletionStage<? extends U> other,        BiConsumer<? super T, ? super U> action)

同时执行两个线程，获取两个返回结果T,U作为参数，进入BiConsumer<T, U>，retrun Void,返回 CompletableFuture<Void>

public static void main(String[] args) {        CompletableFuture<Void> voidCompletableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------开始---");            try {                TimeUnit.SECONDS.sleep(1);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------结束---");            return "hello";        }).thenAcceptBothAsync(CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------开始---");            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------结束---");            return "hello".length();        }), (t, v) -> {            try {                TimeUnit.SECONDS.sleep(5);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "........." + t + "---" + v);        });        System.out.println("---------------------------");        voidCompletableFuture.join();    }

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acceptEitherAsync

acceptEitherAsync(        CompletionStage<? extends T> other, Consumer<? super T> action)

获取快的线程的结果(两个线程返回类型需一致)T，T作为参数，进入Consumer，return void,返回CompletableFuture<Void>

public static void main(String[] args) {        CompletableFuture<Void> voidCompletableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------开始---");            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------结束---");            return "hello1";        }).acceptEitherAsync(CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------开始---");            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------结束---");            return "hello2";        }), t -> {            try {                TimeUnit.SECONDS.sleep(5);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "........." + t);        });        System.out.println("---------------------------");        voidCompletableFuture.join();    }

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runAfterBothAsync

runAfterBothAsync(CompletionStage<?> other, Runnable action)

两个线程执行完毕后,不关心结果,进入Runnable ，return void,返回CompletableFuture<Void>

public static void main(String[] args) {        CompletableFuture<Void> voidCompletableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------开始---");            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------结束---");            return "hello1";        }).runAfterBothAsync(CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------开始---");            try {                TimeUnit.SECONDS.sleep(5);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------结束---");            return "hello2".length();        }), () -> {            System.out.println(Thread.currentThread().getName() + ".........");            try {                TimeUnit.SECONDS.sleep(5);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + ".........");        });        System.out.println("---------------------------");        voidCompletableFuture.join();    }

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runAfterEitherAsync

CompletableFuture<Void> runAfterEitherAsync(CompletionStage<?> other,                                                       Runnable action)

有线程结束后,不关心结果,进入Runnable ，return void,返回CompletableFuture<Void>

public static void main(String[] args) {        CompletableFuture<Void> voidCompletableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------开始---");            try {                TimeUnit.SECONDS.sleep(5);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------结束---");            return "hello1";        }).runAfterEitherAsync(CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------开始---");            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------结束---");            return "hello2".length();        }), () -> {            System.out.println(Thread.currentThread().getName() + ".........");            try {                TimeUnit.SECONDS.sleep(3);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + ".........");        });        System.out.println("---------------------------");        voidCompletableFuture.join();    }

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thenCombineAsync

CompletableFuture<V> thenCombineAsync(        CompletionStage<? extends U> other,        BiFunction<? super T,? super U,? extends V>

同时执行两个线程，获取两个返回结果T,U作为参数，进入BiFunction,return v , CompletableFuture<V>

public static void main(String[] args) {        CompletableFuture<String> completableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------开始---");            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------结束---");            return "hello1";        }).thenCombineAsync(CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------开始---");            System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------结束---");            return 100;        }), (t, u) -> {            System.out.println(Thread.currentThread().getName() + "........." + t);            try {                TimeUnit.SECONDS.sleep(3);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "........." + u);            return "=thenCombine=";        });        try {            System.out.println("---------------------------" + completableFuture.get());        } catch (Exception e) {            e.printStackTrace();        }    }

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thenComposeAsync

CompletableFuture<U> thenComposeAsync(        Function<? super T, ? extends CompletionStage<U>> fn)

public static void main(String[] args) {        CompletableFuture<Integer> completableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------开始---");            try {                TimeUnit.SECONDS.sleep(3);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "---------supplyAsync1---------结束---");            return "hello1";        }).thenComposeAsync(t -> {            CompletableFuture<Integer> integerCompletableFuture = CompletableFuture.supplyAsync(() -> {                System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------开始---" + t);                try {                    TimeUnit.SECONDS.sleep(3);                } catch (Exception e) {                    e.printStackTrace();                }                System.out.println(Thread.currentThread().getName() + "---------supplyAsync2---------结束---" + t);                return 100;            });            return integerCompletableFuture;        });        try {            System.out.println("=----------------------------=");            System.out.println("---------------------------" + completableFuture.get());        } catch (Exception e) {            e.printStackTrace();        }    }

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其它方法

getNow(T valueIfAbsent)：线程执行完了，获取返回的值，如果没有执行完毕，返回指定值。不阻塞。

public static void main(String[] args) {        CompletableFuture<String> stringCompletableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync----begin-------"+ System.currentTimeMillis());            try {                TimeUnit.SECONDS.sleep(3);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "---------supplyAsync-----end------"+ System.currentTimeMillis());            return "hello";        });        //执行完了 获取返回的值，如果没有执行完毕，返回指定值        String now = stringCompletableFuture.getNow("i am getNow value");        System.err.println(Thread.currentThread().getName() + "=====getNow值：" + now + " ====时间： " + System.currentTimeMillis());        try {            System.err.println(Thread.currentThread().getName() + "====get值：" + stringCompletableFuture.get() + "===时间： " + System.currentTimeMillis());        } catch (Exception e) {            e.printStackTrace();        }    }

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complete(T value)：若完成，返回false,get()时获取返回值; 若未完成，返回true,get()时获取指定值。

public static void main(String[] args) {        CompletableFuture<String> stringCompletableFuture = CompletableFuture.supplyAsync(() -> {            System.out.println(Thread.currentThread().getName() + "---------supplyAsync----begin-------"+ System.currentTimeMillis());            try {                TimeUnit.SECONDS.sleep(4);            } catch (Exception e) {                e.printStackTrace();            }            System.out.println(Thread.currentThread().getName() + "---------supplyAsync-----end------"+ System.currentTimeMillis());            return "hello";        });        try {            TimeUnit.SECONDS.sleep(5);        } catch (Exception e) {            e.printStackTrace();        }        //若完成，返回false,get()时获取返回值; 若未完成，返回true,get()时获取指定值        boolean complete = stringCompletableFuture.complete("WWWWW");        System.out.println(complete);        try {            System.out.println(Thread.currentThread().getName() + "  get值：" + stringCompletableFuture.get() + " 时间： " + System.currentTimeMillis());        } catch (Exception e) {            e.printStackTrace();        }    }

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completeExceptionally(Throwable ex)：//若完成，返回false,get()时获取返回值; 若未完成，返回true,get()时抛出指定异常

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