public boolean validated()
    {
	// if there is not data then this object is invalid.
	if(data.elementAt(0) != null) 
	{
	    columns = data.elementAt(0).getDataLength();
	    
	    // Check that each data row agrees on the number 
	    // of columns in the data.
	    for(int i = 0; i < data.size(); i++)
	    {
		// A row does not agree, meaning input data
		// is inconsistent.
		if(data.elementAt(i).getDataLength() != columns)
		    return false;
	    }
	    
	    // If we arrive here then all is well
	    return true;
	}
	else 
	    return false;
    }