Java中的封装试什么意思？

public class Student {
    /*public Student(){}//无参构造器
    public Student(int age){//有参构造器
        this.age=10;
    }*/
     private String name;//属性
    private int age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public void paly(){
        System.out.println(this.name+"在学习"+this.age+"3岁了");
    }


}
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public class ApplicationDemo01 {
    public static void main(String[] args) {
        Student x = new Student();
      x.setName("Jack");
        System.out.println(x.getName());
}}
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