Collections类

Collections类

public class Cat /*implements Comparable<Cat>*/ {//类继承Comparable接口 private String name; public Cat(String name) { this.name = name; } public Cat() { } public String getName() { return name; } public void setName(String name) { this.name = name; } @Override public String toString() { return "Cat{" + "name='" + name + '\'' + '}'; } //重写比较原则 /*@Override public int compareTo(Cat o) { return this.name.compareTo(o.name); }*/ } //比较器 public class CatComparator implements Comparator<Cat> { @Override public int compare(Cat o1, Cat o2) { return o1.getName().compareTo(o2.getName()); } } public class ListTest02 { public static void main(String[] args) { //创建集合 List<Cat> cats = Collections.synchronizedList(new ArrayList<Cat>()); //添加元素 cats.add(new Cat("小咪")); cats.add(new Cat("小喵")); cats.add(new Cat("小咩")); cats.add(new Cat("小缪")); //排序 在排序方法中传入一个比较器 或者在这里写一个匿名内部类 Collections.sort(cats,new CatComparator()); //匿名内部类 /*Collections.sort(cats, new Comparator<Cat>() { @Override public int compare(Cat o1, Cat o2) { return o1.getName().compareTo(o2.getName()); } });*/ //遍历 for (Cat cat : cats) { System.out.println(cat); } } }