Given class Value :
public class Value { private int xVal1; private int xVal2; private double pVal; // constructor of the Value class
You need to locate the exact constructor for this. Class.newInstance() can only be used to call the nullary constructor. So write
Class.newInstance()
final Value v = Value.class.getConstructor( int.class, int.class, double.class).newInstance(_xval1,_xval2,_pval);