java8关于CompletableFuture使用

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package com.xxx.tools.demo.forker;

import lombok.Data;
import org.junit.Test;

import java.util.Arrays;
import java.util.List;
import java.util.Random;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.util.stream.Collectors;

import static com.xxx.tools.demo.forker.CompletableFutureTest.delay;
import static com.xxx.tools.demo.forker.CompletableFutureTest.random;

//import java.util.stream.Stream;

/**
 */
public class CompletableFutureTest {
    List<Shop> shops = Arrays.asList(new Shop("BP1"), new Shop("BP2"), new Shop("BP3"), new Shop("BP4"));
    public final Executor executor = Executors.newFixedThreadPool(Math.max(shops.size(), 100), r->{
        Thread t = new Thread(r);
        t.setDaemon(true);
        t.setName("shopPool");
        return t;
    });
    public final Executor thenCombinePool = Executors.newFixedThreadPool(Math.max(shops.size(), 100), r->{
        Thread t = new Thread(r);
        t.setDaemon(true);
        t.setName("thenCombine");
        return t;
    });
    public static final Random random = new Random();
    public static void delay() {
        int delay = 1000;
        try {
            Thread.sleep(delay);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    public List<CompletableFuture<String>> findPrice(String product){
//    public Stream<CompletableFuture<String>> findPrice(String product){
        return shops.stream()
                .map(shop -> CompletableFuture.supplyAsync(() -> shop.getPrice(product),executor))
//                .map(priceStr->priceStr.thenApply())实时转换
                .map(priceStr->priceStr.thenApply(str->str+":thenApply"))
//                .map(priceStr->priceStr.thenCompose())上一步结果，接着异步(与上一个同步)
                .map(priceStr->priceStr.thenCompose((str) -> CompletableFuture.supplyAsync(
                        ()->{
                            delay();
//                            System.out.println("thenCompose---name:"+Thread.currentThread().getName());
                            return str+":thenCompose";
                        },executor
                )))
//                .map(priceStr->priceStr.thenCombine())上一步结果，和下一个异步结合
                .map(priceStr->priceStr.thenCombine(CompletableFuture.supplyAsync(()->{
                    delay();
//                    System.out.println("thenCombine---name:"+Thread.currentThread().getName());
                    return ":thenCombine";
                },thenCombinePool),(a,b)->a+b))
                .collect(Collectors.toList());

//        return collect.stream()
//                .map(CompletableFuture::join)
//                .collect(Collectors.toList());

    }
    @Test
    public void test1(){
        long start = System.nanoTime();
//        List<String> myPhone = findPrice("myPhone").stream()
//                .map(CompletableFuture::join)
//                .collect(Collectors.toList());
//        System.out.println(myPhone);
//        long run =(System.nanoTime()-start)/1_000_000;
//        System.out.println("1运行了："+run);

        CompletableFuture[] myPhones = (CompletableFuture[]) findPrice("myPhone").stream()
                .map(f -> f.thenAccept(System.out::println))
                .toArray(size -> new CompletableFuture[size]);
        CompletableFuture.allOf(myPhones).join();
        long run1 =(System.nanoTime()-start)/1_000_000;
        System.out.println("2运行了："+run1);

    }


}
@Data
class Shop {
    private String name;
    public Shop(String name) {
        this.name = name;
    }
    public String getPrice(String product){
        return calculatePrice(product);
    }
    private String calculatePrice(String product){
        delay();
        return String.format("%s:%.2f:%s",name,random.nextDouble()*product.charAt(0)+product.charAt(1),Discount.Code.GOLD);
    }
}



for (String B00 : b00s) {
    bzzsglService.synZsxx(B00);
}

改多线程1

ExecutorService executor = Executors.newFixedThreadPool(5);
try{
    List<CompletableFuture<Void>> futures = b00s.stream()
    .map(B00 -> CompletableFuture.runAsync(() -> {
        bzzsglService.synZsxx(B00);
    }, executor))
    .collect(Collectors.toList());

    CompletableFuture.allOf(futures.toArray(new CompletableFuture[0])).join();
}catch (Exception e){
    e.printStackTrace();
}finally {
    executor.shutdown();
}



改多线程2
ExecutorService personThreadPool = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
try{
    List<Future<?>> batchFutures = new ArrayList<>();
    batchFutures.add(personThreadPool.submit(()->{}));
    for (Future<?> f : batchFutures) {
        try {
            f.get();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } catch (ExecutionException e) {
            e.printStackTrace();
        }
    }
}catch (Exception e){
    e.printStackTrace();
}finally {
    personThreadPool.shutdown();
}