how do I write the test for this?

Here is the Java class. Create a Java file - Vector 10. Java and copy the below code. Thank You public clana Vector30 private double x; private dorable y private double si puble Vector3D(double , double y, doable ) this.x - MI this.y - Y this.z. 2; poble double getx1 return x: puble double getY return Yi 1 pablic doble get return; puble double gettagnitude return Math.artixx.yy. 2): override public Steing costringe) return". > pable Vector normalized double mag ganitude): 1 Double.comparete, nag- throw new illegalStateException "Error Vector cannot be normalized } else return tew Vector3D1%/ nav./mag. / nagy 2 public Vector3D add (Vector3D vector3D) { double xxx.vector D.getX()1 double yy - y vector Det double - vector3D.get) return new Vector3D, YY. poble Vector multiply double factor) { double XXX factor double yyy factors double factor return new Vector DIN, YY. ) > puble double dot Product Vector3D vector3D) double xxx vector3D.get double yy y vector 3D.getY(); doubte -vector3D.get return xx.yy. 24; public double angleBetween Vector vector) double den - et Magnitude) vector3D.getMagnitude(); 11 Double.compareo, den) - 0) { throw new illegalstatexception "Error: Vector cannot be normalized); else { return Math.acos (dat Product vector3D) / den) 1