java - 如何在Java中用lambda和stream替换for循环？

如何将以下for循环转换为将Java lambda与流一起使用？

List<Fruit> fruits = createFruitArrayList (); // creates a list of fruits
Fruit largeApple = null;    // holds the largest apple so far for
for (Fruit fruit : fruits) {
  if (fruit.getType () == “Apple”) {
    if (largeApple == null ||
     largeApple.size () < fruit.size ()) {
      largeApple = fruit;
    }
  }
}

最佳答案

您可以使用comparator比较两个值

Comparator<Fruit> comp = (fruit1, fruit2) -> Integer.compare( fruit1.size(), fruit2.size());
Fruit largeApple = fruits.stream().max(comp).get();

而且比较字符串的方法是错误的

if (fruit.getType () == “Apple”)

你想要什么

if (fruit.getType().equals("Apple"))

有关更多信息，请看以下问题：
How do I compare strings in Java?