JAVA8stream 끼 워 넣 기 순환 및 설정 값

    public static void main(String[] args)throws Exception {
        List<IG> igs1 = Arrays.asList(new IG(11),
                                      new IG(12));

        List<IG> igs2 = Arrays.asList(new IG(11),
                                      new IG(13));
        List<IG> igs3 = Arrays.asList(new IG(11),
                                      new IG(13),
                                      new IG(13));

        //找出skuId相同的对象组成集合
        List<IG> gs1 =  igs2.stream().filter(a1 -> igs1.stream().anyMatch(a2 ->a1.getSkuId() == a2.getSkuId())
        ).collect(Collectors.toList());
        //打印输出 tSnipingGoodSkus1{11}
        gs1.stream().map(IG::getSkuId).forEach(System.out::println);

        //对skuId相同的对象属性进行操作
        List<IG> gs2 = igs2.parallelStream().map(a1 ->{//parallelStream :多线程异步stream
            IG tSnipingGoodSku =  igs1.stream().filter(a2 -> a1.getSkuId() == a2.getSkuId()).findFirst().orElse(null); //orElse 值为空返回null防止空指针异常
            if (null != tSnipingGoodSku){
                a1.setSkuId(666);
            }
            return a1;
        }).collect(Collectors.toList());
        //打印输出 tSnipingGoodSkus2{666,13}
        gs2.stream().map(IG::getSkuId).forEach(System.out::println);

        //sorted()方法: 有参从低到高排序（升序），无参从高到底排序（降序）
        List<IG> sortedEmp = igs3.stream().sorted(Comparator.comparing(IG::getSkuId)).collect(Collectors.toList());
        //输出11 13 13
        sortedEmp.stream().map(IG::getSkuId).forEach(System.out::println);
    }


    public static class IG {

        private Integer skuId;

        public Integer getSkuId() {
            return skuId;
        }

        public void setSkuId(Integer skuId) {
            this.skuId = skuId;
        }

        public IG(Integer skuId) {
            this.skuId = skuId;
        }
    }