Java学习----方法的重载

public class Student {
    public Student() {
        System.out.println("Student构造方法1");
    }
    
    public Student(int x, float y) {
        System.out.println("Student构造方法2");
    }
    
    public Student(float x, int y) {
        System.out.println("Student构造方法3");
    }
    
    // 普通方法
    public String study() {
        System.out.println("学习");
        return "study方法1";
    }
    
    public String study(String subject) {
        System.out.println("学习" + subject);
        return "study方法2";
    }
    
    public static void main(String[] args) {
        Student s1 = new Student();
        
        s1.study();
        s1.study("数学");
    }
}

Student构造方法1
学习
学习数学