AP® Computer Science A glossary

Aliasing

Also called: alias

Course: AP® Computer Science A Shows up in: Unit 3: Class Creation

Two or more references that refer to the same object, so a change made through one reference is seen through the others.

Appears in the course and exam description (CED): 3.6.A.13.6.A.2

Aliases are created by assigning one reference variable to another, by passing an object to a method, and by returning a stored object from a method. To avoid aliasing, make a new object with the same values.

public class Point
{
    private int x;

    public Point(int x)
    {
        this.x = x;
    }

    public static void main(String[] args)
    {
        Point p = new Point(1);
        Point q = p;      // q is an alias of p
        q.x = 9;
        System.out.println(p.x);
    }
}

Output:

9

Related terms

• Passing references
• Object reference
• Object