Java 8 流优化

Question

我有一个下面的代码库，用于查找任何匹配的对象及其状态失败，实现下面代码的最简化方法是什么

DummyCounter dummyCounter=new DummyCounter();
dummyCounter.setDue("DONE");
dummyCounter.setStatus(1);

DummyCounter dummyCounte1=new DummyCounter();
dummyCounte1.setDue("FAILRUE");
dummyCounte1.setStatus(1);

DummyCounter dummyCounte2=new DummyCounter();
dummyCounte2.setDue("DONE");
dummyCounte2.setStatus(1);

List<DummyCounter>  counterList=new ArrayList<DummyCounter>();
counterList.add(dummyCounter);
counterList.add(dummyCounte2);
counterList.add(dummyCounte2);

用法

final Integer integer = counterList.stream()
       .filter(customer -> "DONE".equals(customer.getDue()))
       .map(DummyCounter::getStatus)
       .filter(Objects::nonNull)
       .findAny()
       .get();

System.out.println(integer);

Answer 1

要查找所有失败的条目，您可以执行以下操作：

List<DummyCounter> failedDummies = counterList.stream()
      .filter(dummy-> "FAILURE".equals(dummy.getDue()))
      .collect(Collectors.toList());

查找失败计数：

int totalFailedCounters = counterList.stream()
          .filter(dummy-> "FAILURE".equals(dummy.getDue()))
          .collect(Collectors.toList()).size();