头等舱(父类)
package revisionOOP;
public class Myclass {
private int x;
public void changeThis() {
x = 10;
System.out.println("x = " + x);
}
//getter
public int UnprivateX() {
return this.x;
}
public static void main(String[] args) {
Myclass inst = new Myclass();
inst.changeThis();
}
}
另一个类(子类)
package revisionOOP;
public class MySecondClass extends Myclass {
static int y;
public void changeExThis() {
y = 20;
System.out.println("x = " + inst.UnprivateX());
//I want to get the private x value from Myclass class ,How ?
System.out.println("y = " + y);
}
public static void main(String[] args) {
MySecondClass inst = new MySecondClass();
Myclass inst2 = new Myclass();
inst2.changeThis();
inst.changeThis();
inst.changeExThis();
}
}
如何使用getter函数访问另一个类中的私有变量?在子类中如何更改它?
您可以在像这样的孩子中使用方法
public void changeExThis() {
y = 20;
System.out.println("x = " + UnprivateX());
System.out.println("y = " + y);
}
也可以使用this.UnprivateX()
或super.UnprivateX()
首先,应该将类的所有字段声明为私有字段,然后为每个字段创建getter和setter,它们的名称必须以getFieldName&setFieldName开头。并且应该是公开的。