for (BlockSubscription blockSubscription : blockSubscriptions) { for (BlockSubscriptionData blockSubscriptionData : subscriptionCountList) { if (blockSubscription.getId() == blockSubscriptionData.getActivityId()){ blockSubscription.setSubscriptionCount(blockSubscriptionData.getSubscriptionCount()); } } for (BlockSubscriptionData blockSubscriptionData : subscriptionPeopleCountList) { if (blockSubscription.getId() == blockSubscriptionData.getActivityId()){ blockSubscription.setSubscriptionPeopleCount(blockSubscriptionData.getSubscriptionPeopleCount()); } } }使用Stream优化

可以使用Stream API对这段代码进行优化，如下所示：

blockSubscriptions.forEach(blockSubscription -> {
    subscriptionCountList.stream()
        .filter(data -> blockSubscription.getId() == data.getActivityId())
        .findFirst()
        .ifPresent(data -> blockSubscription.setSubscriptionCount(data.getSubscriptionCount()));
    
    subscriptionPeopleCountList.stream()
        .filter(data -> blockSubscription.getId() == data.getActivityId())
        .findFirst()
        .ifPresent(data -> blockSubscription.setSubscriptionPeopleCount(data.getSubscriptionPeopleCount()));
});

这段代码使用了Stream的filter和findFirst方法，避免了多层嵌套循环的问题，提高了代码的可读性和性能。

相关问题

for (BlockSubscription blockSubscription : blockSubscriptions) { for (BlockSubscriptionData blockSubscriptionData : subscriptionCountList) { if (blockSubscription.getId() == blockSubscriptionData.getActivityId()){ blockSubscription.setSubscriptionCount(blockSubscriptionData.getSubscriptionCount()); } } for (BlockSubscriptionData blockSubscriptionData : subscriptionPeopleCountList) { if (blockSubscription.getId() == blockSubscriptionData.getActivityId()){ blockSubscription.setSubscriptionPeopleCount(blockSubscriptionData.getSubscriptionPeopleCount()); break; } } } 使用 stream优化

可以使用 Java 8 引入的 Stream API 来优化上述代码。具体实现方式如下：

blockSubscriptions.forEach(blockSubscription ->
        subscriptionCountList.stream()
                .filter(blockSubscriptionData -> blockSubscription.getId() == blockSubscriptionData.getActivityId())
                .findFirst()
                .ifPresent(blockSubscriptionData -> blockSubscription.setSubscriptionCount(blockSubscriptionData.getSubscriptionCount())));

blockSubscriptions.forEach(blockSubscription ->
        subscriptionPeopleCountList.stream()
                .filter(blockSubscriptionData -> blockSubscription.getId() == blockSubscriptionData.getActivityId())
                .findFirst()
                .ifPresent(blockSubscriptionData -> blockSubscription.setSubscriptionPeopleCount(blockSubscriptionData.getSubscriptionPeopleCount())));

上面的代码中，我们使用 forEach 方法遍历 blockSubscriptions 列表，然后使用 Stream API 进行过滤、查找以及设置属性值。这样做的好处是代码更加简洁，可读性更高，同时也可以提高代码的执行效率。