Re: access levels for private field which is inherited

On Sun, 13 Apr 2008 09:37:03 -0700, Mark Space wrote:


I want to use the factory method, but am running into a conceptual
problem with regards to packages, interfaces and casting. If I make
StudentDescriptor an interface then things would would work, or maybe a
cast? I'd like to keep StudentDescriptor an abstract class which Student
extends, and use the factory pattern.

I've seemingly painted myself into a corner with:

bcit@arrakis:~/java/src$
bcit@arrakis:~/java/src$ javac -d /home/bcit/java/prod/ -cp . a00720398/
Lab1.java a00720398/data/*.java
a00720398/Lab1.java:13: incompatible types
found : a00720398.data.StudentDescriptor
required: a00720398.data.Student
                        Student student = Student.newStudent();
                                                            ^
1 error
bcit@arrakis:~/java/src$
bcit@arrakis:~/java/src$ cat a00720398/data/StudentDescriptor.java
package a00720398.data;

class StudentDescriptor
implements HasName, HasNumber {

        private String name = MY_NAME;
        private String number = MY_NUMBER;

        public StudentDescriptor() {}

        public static StudentDescriptor newInstance() {
                return new StudentDescriptor();
        }

        public String getName() {
                return name;
        }

        public String getNumber() {
                return number;
        }

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

        public void setNumber(String number) {
                this.number = number;
        }

        public String toString(){
                return getNumber() + ", " + getName();
        }

}
bcit@arrakis:~/java/src$
bcit@arrakis:~/java/src$ cat a00720398/data/Student.java
package a00720398.data;

public class Student extends StudentDescriptor {

        public static StudentDescriptor newStudent() {
                return StudentDescriptor.newInstance();
        }

}
bcit@arrakis:~/java/src$

thanks,

Thufir