Java优学网Lambda表达式入门解析：告别繁琐匿名类，轻松掌握函数式编程

// 传统方式 Comparator oldWay = new Comparator() {

@Override
public int compare(String s1, String s2) {
    return s1.compareTo(s2);
}

};

// Lambda方式 Comparator newWay = (s1, s2) -> s1.compareTo(s2);

// 匿名内部类方式 new Thread(new Runnable() {

@Override
public void run() {
    System.out.println("任务执行中");
}

}).start();

// Lambda表达式方式 new Thread(() -> System.out.println("任务执行中")).start();

@FunctionalInterface public interface Runnable {

public abstract void run();

}

List words = Arrays.asList("apple", "banana", "cherry", "date"); List filteredWords = words.stream()

.filter(word -> word.length() > 5)
.map(String::toUpperCase)
.collect(Collectors.toList());

// Lambda表达式 list.forEach(s -> System.out.println(s));

// 方法引用 list.forEach(System.out::println);