java8中lamba表达式的使用

JButton jButton = new JButton("123");
　　jButton.addActionListener(new ActionListener() {
　　@Override
　　public void actionPerformed(ActionEvent e) {}});

jButton.addActionListener(e->System.out.println("Hello world"));
　　jButton.addActionListener((e)->System.out.println("Hello world"));
　　jButton.addActionListener((ActionEvent e)->System.out.println("Hello world"));
　　jButton.addActionListener((ActionEvent e)->{System.out.println("Hello world");return;});

Runnable runnable = ()->System.out.println(sign);
　　Runnable runnable2 = new Runnable() {
　　@Override
　　public void run() {
　　// TODO Auto-generated method stub}
　　};
　　通过匿名内部类我们知道run方法是不需要参数的
　　System.out.println(sign) 相当于run方法的方法体
　　Comparator<Integer> lol = (x,y)->x-y;
　　Comparator<Integer> lol = (x,y)->{System.out.println(x+y);return x-y;};
　　new Comparator<Integer>() {
　　@Override
　　public int compare(Integer o1, Integer o2) {
　　// TODO Auto-generated method stub
　　return 0;
　　}
};

int[] oop = {3,1,2,1};
　　static void sayHello(Integer name)
　　{
　　System.out.println(123);
　　}
　　Arrays.stream(oop).forEach(Test::sayHello);
　　Arrays.stream(oop).forEach(s->Test.sayHello(s));

Stream<Object> strings = shapelist.stream().<Object>map(s->s.getColor());
　　s.getColor())

int sum = Arrays.stream(oop).sum();
int sum1 = Arrays.stream(oop).reduce(0,(x,y)->x+y);

public class Shape
　　{
　　private String color;
　　public Shape() {
　　// TODO Auto-generated constructor stub
　　}
　　public String getColor() {
　　return color;
　　}
　　public void setColor(String color) {
　　this.color = color;
　　}
　　public Shape(String color)
　　{
　　this.color = color;
　　}
　　}
　　ArrayList<String> colorList = new ArrayList<String>(){
　　{
　　add("Red");
　　add("Blue");
　　add("Yellow");
　　}
　　};
　　List<Shape> shapeList = colorList.stream().map(Shape::new).collect(Collectors.toList());
　　List<String> colos = shpaeList.stream().map(s->s.getColor()).collect(Collectors.toList());
　　Set<String> colosSet = shpaeList.stream().map(s->s.getColor()).collect(Collectors.toSet());
　　Map<String, String> colorMap = colorList.stream().collect(Collectors.toMap(a->a,s->s));
　　Map<String,Shape> shapesMap = shpaeList.stream().collect(Collectors.toMap(s->s.getColor(), s->s));

Map<String,Set<Shape>> shapeMapSet = shpaeList.stream().collect(Collectors.groupingBy(s->s.getColor(),Collectors.toSet()));
　　Map<String,Map<String, List<Shape>>> shapeMap3 = shpaeList.stream().collect(Collectors.groupingBy(s->s.getColor(),Collectors.groupingBy(s->s.getColor(),Collectors.toList())));

　Iterable.forEach(Consumer)，Collection.removeAll(Predicate)，List.replaceAll(UnaryOperator)，List.sort(Comparator)和Map.computeIfAbsent()等
　　shpaeList.sort(Comparator.comparing(Shape::getColor));