记录一个Comparator例子

public class Main { public static void main(String[] args) { Queue<User> q = new PriorityQueue<>(new Comparator<User>() { public int compare(User u1, User u2) { if (u1.number.charAt(0) == u2.number.charAt(0)) { // 如果两人的号都是A开头或者都是V开头,比较号的大小: return u1.number.compareTo(u2.number); } if (u1.number.charAt(0) == 'V') { // u1的号码是V开头,优先级高: return -1; } else { return 1; } } }); // 添加3个元素到队列: q.offer(new User("Bob", "A1")); q.offer(new User("Alice", "A2")); q.offer(new User("Boss", "V1")); System.out.println(q.poll()); // Boss/V1 System.out.println(q.poll()); // Bob/A1 System.out.println(q.poll()); // Alice/A2 System.out.println(q.poll()); // null,因为队列为空 } } class User { public final String name; public final String number; public User(String name, String number) { this.name = name; this.number = number; } public String toString() { return name + "/" + number; } } public class Main { public static void main(String[] args) { Queue<User> q = new PriorityQueue<>(new UserComparator()); // 添加3个元素到队列: q.offer(new User("Bob", "A1")); q.offer(new User("Alice", "A2")); q.offer(new User("Boss", "V1")); System.out.println(q.poll()); // Boss/V1 System.out.println(q.poll()); // Bob/A1 System.out.println(q.poll()); // Alice/A2 System.out.println(q.poll()); // null,因为队列为空 } } class UserComparator implements Comparator<User> { public int compare(User u1, User u2) { if (u1.number.charAt(0) == u2.number.charAt(0)) { // 如果两人的号都是A开头或者都是V开头,比较号的大小: return u1.number.compareTo(u2.number); } if (u1.number.charAt(0) == 'V') { // u1的号码是V开头,优先级高: return -1; } else { return 1; } } } class User { public final String name; public final String number; public User(String name, String number) { this.name = name; this.number = number; } public String toString() { return name + "/" + number; } }