If Else and Exception in JForm

Question

I am trying to throw the exception when the user enters other integer than 1 and 2 into the jtextfield,

public class SearchEmployee extends javax.swing.JFrame  {

    /**
     * Creates new form SearchEmployee
     */
    public SearchEmployee() {
        
        initComponents();

    }
     // A utility function to check
    // whether a code is valid or not
       public static boolean isCodeValid(String id)
        throws IdNotFoundException
    {
        if(!id.equals("1")){
            throw new IdNotFoundException();
        }else if(!id.equals("2")){
            throw new IdNotFoundException();
        }
        else{
            return true;
        }
    }

and supposedly after users clicked the search button, they are supposedly going to the new page where employee details will be displayed.

 private void searchActionPerformed(java.awt.event.ActionEvent evt) {                                       
        // TODO add your handling code here:
        String id = staffID.getText();

        try{
            if(isCodeValid("1")){
                EmployeeDetails emp = new EmployeeDetails();
                emp.name.setText("Sky Peach");
                emp.email.setText("[email protected]");
                emp.address.setText("Pangsapuri Sri Puteri");
                emp.phoneNo.setText("1999999999");
                emp.department.setText("IT");
                emp.designation.setText("Software Developer");
                emp.show();
            }else if(isCodeValid("2")){
                EmployeeDetails emp = new EmployeeDetails();
                emp.name.setText("Sky Orange");
                emp.email.setText("[email protected]");
                emp.address.setText("Pangsapuri Sri Puteri");
                emp.phoneNo.setText("2999999999");
                emp.department.setText("IT");
                emp.designation.setText("Software Engineer");
                emp.show();
            }
        }catch (IdNotFoundException ex) {
                JOptionPane.showMessageDialog(this, ex.getMessage());
            }
        
        
        
  
    }   

however, the exception was thrown even when i entered the integer 1 and 2. How to fix this error?

Answer 1

Expanding on Rogue and DevilsHnd answer in the comments, I would suggest to switch the arguments used for the string comparison. This avoids NPEs when the id parameter is null.

public static boolean isCodeValid(String id) { return "1".equals(id) || "2".equals(id); }

Or make an excplicit null check (defensive programming) before. The approach with the regex is simpler to expand

public static boolean isCodeValid(String id) { 
    Objects.requireNonNull(id);
    return id.matches("[12]"); 
}