Comparable接口的使用：（知识回顾）

爱被打了一巴掌 2022-09-04 11:59 156阅读 0赞

### Comparable接口的使用：（知识回顾） ###

#### 1、定义一个学生类，具有年龄age和姓名username两个属性，并通过Comparable接口提供比较规则。 ####

package demo02.sort;
    public class Student implements Comparable<Student>{
        
        private String username;
        private int age;
    
        public String getUsername() {
        
            return username;
        }
    
        public int getAge() {
        
            return age;
        }
    
        public void setUsername(String username) {
        
            this.username = username;
        }
    
        public void setAge(int age) {
        
            this.age = age;
        }
    
        @Override
        public String toString() {
        
            return "Student{" +
                    "username='" + username + '\'' +
                    ", age=" + age +
                    '}';
        }
    
        @Override
        public int compareTo(Student o) {
        
            return this.getAge()-o.getAge();
        }
    }

#### 2、定义测试类TestComparable，在测试类Test中定义测试方法Comparable getMax（comparable c1，comparable c2）完成测试 ####

package demo02.test;
    import demo02.sort.Student;
    public class TestComparable {
        
        public static void main(String[] args) {
        
            Student s1 = new Student();
            s1.setUsername("张三");
            s1.setAge(18);
    
            Student s2 = new Student();
            s2.setUsername("李四");
            s2.setAge(20);
    
            Comparable max = getMax(s1, s2);
    
            System.out.println(max);
        }
    
        public static Comparable getMax(Comparable c1, Comparable c2) {
        
            int result = c1.compareTo(c2);
            //如果result>0，则c1比c2大，如果result<0，则c2比c1大如果result=0，则c1==c2大
            if (result >= 0) {
        
                return c1;
            } else {
        
                return c2;
            }
        }
    }

**运行结果**：

![image-20210811161236197][]

[image-20210811161236197]: /images/20220829/00ea3a1884ac409cab2308215114a74c.png