How to check if an unset object has attributes

hh_vv :

I'm trying to form a method to call on a object to check if it contains some of the attributes in the class

This is the code that I've tried so far

public class BoundingBox {

    public int x, y, width, height;

    public BoundingBox() {

    }

    public Integer getX() {
        return x;
    }

    public void setX(Integer x) {
        this.x = x;
    }

    public Integer getY() {
        return y;
    }

    public void setY(Integer Y) {
        this.y = y;
    }

    public boolean contains(int x, int y) {
        if (x == getX() & y == getY()) {
            return true;
        } else {
            return false;
        }
    }
}

However when I created the object with all attributes holding the value of 10 and tested it using object.contains(15,15), it does not return false

Louis :

In Java the operator & can assume different meanings:

• & : Bitwise operator
• && : Logical operator

In the if statement if (x == getX() & y == getY()) { you used the & bitwise operator instead of the && logical operator.
Plus there was a typo in the setY method and, as stated by @alvinalvord, comparing int with Integer can give unexpected results.

Change your code like this and it will work:

public class BoundingBox {

    public int x, y, width, height;

    public BoundingBox() {

    }

    public Integer getX() {
        return x;
    }

    public void setX(Integer x) {
        this.x = x;
    }

    public Integer getY() {
        return y;
    }

    public void setY(Integer y) {
        this.y = y;
    }

    public boolean contains(int x, int y) {
        return getX().equals(x) && getY().equals(y);
    }
}

---

Alternative Code

Or, if there's no particular reason to keep the Integer variables, you can change the code like this:

public class BoundingBox {

    public int x, y, width, height;

    public BoundingBox(int x, int y) {
        this.x = x;
        this.y = y;
    }

    public int getX() {
        return x;
    }

    public void setX(int x) {
        this.x = x;
    }

    public int getY() {
        return y;
    }

    public void setY(int y) {
        this.y = y;
    }

    public boolean contains(int x, int y) {
        return getX() == x && getY() == y;
    }
}