1.异步处理(最常用)
runAsync(Runnable runnable,Executor executor)
supplyAsync(Supplier<U> supplier, Executor executor)
2.completeFuture结果处理
CompletableFuture<U> thenApply( Function<? super T,? extends U> fn)
CompletableFuture<Void> thenAccept(Consumer<? super T> action)
CompletableFuture<V> thenCombine(CompletionStage<? extends U> other, BiFunction<? super T,? super U,? extends V> fn)
3.多个completeFuture并行控制
CompletableFuture<Void> allOf(CompletableFuture<?>... cfs)
CompletableFuture<Object> anyOf(CompletableFuture<?>... cfs)
常用方法说明:
thenCombine -合并两个线程任务的结果,并进一步处理。
applyToEither-两个线程任务相比较,先获得执行结果的,就对该结果进行下一步的转化操作。
acceptEither-两个线程任务相比较,先获得执行结果的,就对该结果进行下一步的消费操作。
runAfterEither-两个线程任务相比较,有任何一个执行完成,就进行下一步操作,不关心运行结果。
runAfterBoth-两个线程任务相比较,两个全部执行完成,才进行下一步操作,不关心运行结果。
anyOf-anyOf 方法的参数是多个给定的 CompletableFuture,当其中的任何一个完成时,方法返回这个 CompletableFuture。
allOf-allOf方法用来实现多 CompletableFuture 的同时返回。
测试用例:
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.function.BiConsumer;
import java.util.function.Function;
public class CompleteFutureTest {
public static void main(String[] args) throws ExecutionException, InterruptedException {
// step1:异步执行
Runnable runnable = () -> {
System.out.println("执行无返回结果的异步任务-开始");
try {
TimeUnit.SECONDS.sleep(5);
} catch (InterruptedException e) {
e.printStackTrace();
System.out.println("执行无返回结果的异步任务-结束");
CompletableFuture.runAsync(runnable);
// step2:异步执行 阻塞获取结果
CompletableFuture<String> future = CompletableFuture.supplyAsync(() -> {
System.out.println("执行有返回值的异步任务");
try {
TimeUnit.SECONDS.sleep(5);
} catch (InterruptedException e) {
e.printStackTrace();
return "Hello World";
String result = future.get();
System.out.println(result);
// step3:异步执行 阻塞获取结果后对结果进行运算处理 不改变最终结果
String result2 = future.whenComplete(new BiConsumer<String, Throwable>() {
@Override
public void accept(String t, Throwable action) {
t = t + 1;
System.out.println("任务执行后结果处理");
}).exceptionally(new Function<Throwable, String>() {
@Override
public String apply(Throwable t) {
System.out.println("任务执行后结果额外处理-如果有异常进入此处");
return "异常结果";
}).get();
System.out.println("最终结果" + result2);
// step4:
// thenCombine会将两个任务的执行结果作为所提供函数的参数,且该方法有返回值;
// thenAcceptBoth同样将两个任务的执行结果作为方法入参,但是无返回值;
// runAfterBoth没有入参,也没有返回值。注意两个任务中只要有一个执行异常,则将该异常信息作为指定任务的执行结果
CompletableFuture<Integer> cf1 = CompletableFuture.supplyAsync(() -> {
System.out.println(Thread.currentThread() + " cf1 do something....");
return 1;
CompletableFuture<Integer> cf2 = CompletableFuture.supplyAsync(() -> {
System.out.println(Thread.currentThread() + " cf2 do something....");
return 2;
CompletableFuture<Integer> cf3 = cf1.thenCombine(cf2, (a, b) -> {
System.out.println(Thread.currentThread() + " cf3 do something....");
return a + b;
System.out.println("cf3结果->" + cf3.get());
CompletableFuture<Integer> cf4 = CompletableFuture.supplyAsync(() -> {
System.out.println(Thread.currentThread() + " cf4 do something....");
return 1;
CompletableFuture<Integer> cf5 = CompletableFuture.supplyAsync(() -> {
System.out.println(Thread.currentThread() + " cf5 do something....");
return 2;
CompletableFuture<Void> cf6 = cf4.thenAcceptBoth(cf5, (a, b) -> {
System.out.println(Thread.currentThread() + " cf6 do something....");
System.out.println("处理结果不返回:"+(a + b));
System.out.println("cf3结果->" + cf6.get());
// step5:
//allOf:
// CompletableFuture是多个任务都执行完成后才会执行,只有有一个任务执行异常,则返回的CompletableFuture执行get方法时会抛出异常,如果都是正常执行,则get返回null。
//anyOf:
// CompletableFuture是多个任务只要有一个任务执行完成,则返回的CompletableFuture执行get方法时会抛出异常,如果都是正常执行,则get返回执行完成任务的结果。
CompletableFuture<String> cf7 = CompletableFuture.supplyAsync(() -> {
try {
System.out.println(Thread.currentThread() + " cf7 do something....");
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
System.out.println("cf7 任务完成");
return "cf7 任务完成";
CompletableFuture<String> cf8 = CompletableFuture.supplyAsync(() -> {
try {
System.out.println(Thread.currentThread() + " cf8 do something....");
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
System.out.println("cf8 任务完成");
return "cf8 任务完成";
CompletableFuture<String> cf9 = CompletableFuture.supplyAsync(() -> {
try {
System.out.println(Thread.currentThread() + " cf9 do something....");
Thread.sleep(3000);
} catch (InterruptedException e) {
e.printStackTrace();
System.out.println("cf9 任务完成");
return "cf9 任务完成";
CompletableFuture<Void> cfAll = CompletableFuture.allOf(cf7, cf8, cf9);
System.out.println("cfAll结果->" + cfAll.get());
CompletableFuture<Object> cfAny = CompletableFuture.anyOf(cf7, cf8, cf9);
System.out.println("cfAny结果->" + cfAny.get());