This tutorial will teach you how to make make a Currency Converter Using Java step by step. Paste the below the code inside the convert button. private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { Double tot; Double amount = Double.parseDouble(txtamount.getText()); if(txtfrom.getSelectedItem().toString() == "USD" && txtto.getSelectedItem().toString() == "Srilankan Rupees") { tot = amount * 179.50; JOptionPane.showMessageDialog(this, "Your Amount will be " + tot.toString()); } …