Java reflection: Inject data generically and safely

I have become interested in reflection and I wrote a class to wrap an Object so that I can access its private instance fields. The code works great. I do not need to wory about the exceptions in the get() and set() methods because I cast the values appropriately through my wrappers accessor/mutators, but I was wondering if there is a better way of dealing with different types?

Example

public class Driver {
    public static void main(String... args) {
        Point p = new Point();

        System.out.printf("Point initialized: %s\n", p);

        PointDecorator mp = new PointDecorator(p);

        mp.setX(2);
        mp.setY(4);

        p = mp.getPoint();

        System.out.printf("Point updated:     %s\n", p);
    }
}

Output

Point initialized: (0, 0)
Point updated:     (2, 4)

As you can see, I have modified the Point Objects fields, although they are inaccessible through traditional method calls. I was able to bypass Java's typechecking which I find both neat and dangerous. Does this mean that anyone can just wrap another persons class, unless it is immutable, and inject data?

Point.java

public class Point {
    private int x, y;

    public Point() {
        this(0, 0);
    }

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

    public String toString() {
        return String.format("(%d, %d)", x, y);
    }
}

PointDecorator.java

import java.lang.reflect.Field;

public class PointDecorator extends Point {

     protected Point point;

    public PointDecorator(Point point) {
        this.point = point;
    }

    public void setX(int x) {
        set("x", x);
    }

    public int getX() {
        return (Integer) get("x");
    }

    public void setY(int y) {
        set("y", y);
    }

    public int getY() {
        return (Integer) get("y");
    }

    public Point getPoint() {
        return point;
    }

    protected Object get(String fieldName) {
        try {
            return field(fieldName).get(point);
        } catch (Exception e) { }

        return null;
    }

    protected void set(String fieldName, Object value) {
        try {
            field(fieldName).set(point, value);
        } catch (Exception e) { }
    }

    private Field field(String fieldName) {
        try {
            Field f = point.getClass().getDeclaredField(fieldName);
            f.setAccessible(true);
            return f;
        } catch (Exception e) { }

        return null;
    }
}