Java学习----一个对象怎么调用另一个对象呢？

打包

jar cvfm test1.jar manifmest.mf teacher.class student.class test1.class

运行

java -jar test1.jar

public class Teacher {
    private String name;
    private String subject;
    
    public Teacher() {}
    
    public Teacher(String name, String subject) {
        this.name = name;
        this.subject = subject;
    }
    
    public void teaching() {
        System.out.println(name + "is teaching" + subject);
    }
}

public class Student {
    private String name;
    
    public Student() {}
    
    public Student(String name) {
        this.name = name;
    }
    
    public String getName() {
        return name;
    }
    
    public void study(Teacher teacher) {
        // 调用Teacher 类(1)
        //Teacher teacher1 = new Teacher("cindy", "software programming");
        
        teacher1.teaching();
        System.out.println(name + "is studying.....");
    }
}

public class Test1 {
    public static void main(String[] args) {
        Teacher teacher1 = new Teacher("cindy", "software programming");
        Student stu1 = new Student("jack");
        //stu1.study();
        
        // 调用Teacher(2)
        stu1.study(teacher1);
    }
}