避坑 | Java8使用并行流(ParallelStream)注意事项

示例分析

/**
 * 避坑 | Java8使用并行流(ParallelStream)注意事项
 *
 * @author WH.L
 * @date 2020/12/26 17:14
 */
public class TestParallelStream {
    public static void main(String[] args) {
        printFun();
    }
    public static void printFun() {
        List<Integer> integersList = new ArrayList<>();
        for (int i = 0; i < 100; i++) {
            integersList.add(i);
        }
        //普通集合 存储
        List<Integer> parallelStorage = new ArrayList<>();
        //同步集合 存储
        List<Integer> parallelStorage2 = Collections.synchronizedList(new ArrayList<>());
        //通过并行流存入普通集合parallelStorage中
        integersList
                .parallelStream()
                .filter(i -> i % 2 == 0)
                .forEach(i -> parallelStorage.add(i));
        System.out.println("开始打印普通集合parallelStorage");
        parallelStorage
                .stream()
                .forEachOrdered(e -> System.out.print(e + " "));
        System.out.println();
        System.out.print("------------------------------------");
        System.out.println();
        //通过并行流存入同步集合parallelStorage2中
        integersList
                .parallelStream()
                .filter(i -> i % 2 == 0)
                .forEach(i -> parallelStorage2.add(i));
        System.out.println("开始打印同步集合parallelStorage");
        parallelStorage2
                .stream()
                .forEachOrdered(e -> System.out.print(e + " "));
    }
}