private void NumberMinus10ActionPerformed(
     java.awt.event.ActionEvent evt) { // GEN-FIRST:event_NumberMinus10ActionPerformed
   int temp = Integer.parseInt(NumberField.getText()) - 10;
   if (temp < 0) {
     temp = 0;
   }
   NumberField.setText(String.valueOf(temp));
 } // GEN-LAST:event_NumberMinus10ActionPerformed
 private void NumberPlusTenActionPerformed(
     java.awt.event.ActionEvent evt) { // GEN-FIRST:event_NumberPlusTenActionPerformed
   int temp = Integer.parseInt(NumberField.getText()) + 10;
   if (temp < 0) {
     temp = 0;
   }
   NumberField.setText(String.valueOf(temp)); // TODO add your handling code here:
 } // GEN-LAST:event_NumberPlusTenActionPerformed
 private void BackspaceButtonActionPerformed(
     java.awt.event.ActionEvent evt) { // GEN-FIRST:event_BackspaceButtonActionPerformed
   if (NumberField.getCaretPosition()
       != 0) { // only do something if the caret is not the at the beginning
     int tmpcaretpos = NumberField.getCaretPosition();
     NumberField.setText(
         NumberField.getText().substring(0, NumberField.getCaretPosition() - 1)
             + NumberField.getText()
                 .substring(NumberField.getCaretPosition(), NumberField.getText().length()));
     NumberField.setCaretPosition(tmpcaretpos - 1);
   }
 } // GEN-LAST:event_BackspaceButtonActionPerformed
 private void DelButtonActionPerformed(
     java.awt.event.ActionEvent evt) { // GEN-FIRST:event_DelButtonActionPerformed
   if (NumberField.getCaretPosition()
       != NumberField.getText().length()) { // only do something if the caret is not the at the end
     int tmpcaretpos = NumberField.getCaretPosition();
     NumberField.setText(
         NumberField.getText().substring(0, NumberField.getCaretPosition())
             + NumberField.getText()
                 .substring(NumberField.getCaretPosition() + 1, NumberField.getText().length()));
     NumberField.setCaretPosition(tmpcaretpos);
   }
 } // GEN-LAST:event_DelButtonActionPerformed
 void AppendCharacter(String character) {
   int tmpcaretpos =
       NumberField
           .getCaretPosition(); // save positon of the caret so we can use it again after replacing
                                // the string
   NumberField.setText(
       NumberField.getText().substring(0, NumberField.getCaretPosition())
           + character
           + NumberField.getText()
               .substring(NumberField.getCaretPosition(), NumberField.getText().length()));
   NumberField.setCaretPosition(tmpcaretpos + 1); // use the save caret position again
   NumberField.getCaret().setVisible(true);
 }
 private void NumberClearActionPerformed(
     java.awt.event.ActionEvent evt) { // GEN-FIRST:event_NumberClearActionPerformed
   NumberField.setText("");
 } // GEN-LAST:event_NumberClearActionPerformed