private void jButtonCalcActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButtonCalcActionPerformed
        /**This method calculates Monthly Mortgage Payment**/ 
        
        /**Get Input**/
        
        //Get the vlaue of the text fiels
        sPrinciple = jTextFieldPrincipal.getText();
        //add error checking
        sAnualInterest = jTextFieldInterest.getText();
        //add error checking
        sTermYr = jTextFieldTerm.getText();
        
        //error checking
        if(sPrinciple.isEmpty()||sAnualInterest.isEmpty()||sTermYr.isEmpty()){
            ErrorLabel.setText("Incorrect or missing value");
            return;}
        
        //convert strings to numbers
        dPrinciple = Double.parseDouble(sPrinciple); //Amount Barrowed            
        dInterest = Double.parseDouble(sAnualInterest); //Anual interest Rate
        iYearTerm = Integer.parseInt(sTermYr); // Loan Payback Period in Years
        
        //TODO add error checking
        
        //get monthly payment info
        dMonthlyPayment=getMoPayment(iYearTerm, dInterest, dPrinciple);
        
        //Formats Monthly Payment
        currency = NumberFormat.getCurrencyInstance(); //creates currency
        sMonthlyPayment=currency.format(dMonthlyPayment);
        
        //write output
        jTextFieldMoPay.setText(sMonthlyPayment);
    }//GEN-LAST:event_jButtonCalcActionPerformed