java.lang.reflect.field getText when field is JTextfield

Question

I have a class with over 50 JTextfield they all contain text

How to get the text from all Textfield without calling the fields in the code again.

I tried:

    Field[] fields = getClass().getDeclaredFields();       
    for (Field field : fields) {        
        if (field.getName().contains("_") == true) {
            // .getText();
        }
    }

Then I must get the text from the fields but how to manage this??

Or have someone a better idea to the the values??

Answer 1

As Hovercraft Full Of Eels suggested, a clean implementation separates the matter : grouping fields gather and performing a processing on them. Especially, if grouping is performed by reflection.
The following code is more readable and maintainable.

public class MyComponent extends JFrame{
  List<JTextField> fields = new ArrayList(); 

  private JTextField textField1;
  private JTextField textField2;
  private JTextField textField3;

  public MyComponent(){
   textField1 = new JTextField ("");
   textField2 = new JTextField ("");
   textField3 = new JTextField ("");
   addTextFieldInList(textField1, textField2, textField3);
  }

  public void addTextFieldInList(JTextField fieldArgs...) {
    fields.addAll(Arrays.asList(fieldArgs));
  }

  public void iterateAllTextFields(){
    for (JTextField field : fields){
      String yourValue = field.getText();
    }    
}

---

UPDATE after the update of the question where it is specified that the processing handle more than over 50 JTtextField.

In this case, another solution that which I proposed could be more suitable. Indeed, with a dozen of fields, risking to forget to add a JTextField in the list is not very probable but with over 50, we can understand that is a error-prone processing. Creating your custom JTextField is maybe a better alternative. The idea is the following : extending the JTextField with a new class JTextFieldWatched and forcing JTextFieldWatched constructor with an additional parameter : a object which registers JTextField instances.

JTextFieldWatched which extends JTextField :

public class JTextFieldWatched extends JTextField{
  public JTextFieldWatched(String text, JTextFieldWatcher textFieldWatcher){
    super(text);
    if (textFieldWatcher==null){
      // force the constraint
      throw new IllegalArgumentException("textFieldWatcher is mandatory");
    }        
     textFieldWatcher.add(this);
  }
}

A class which registers JTextfield instances :

public class JTextFieldWatcher {
   List<JTextField> fields = new ArrayList(); 

   public void add(JTextField textField){
      fields.add(textField);
   }   

   public List<JTextField> getAllTextField(){
      return new ArrayList(fields);
   }
}

How to use these classes:

public class MyComponent extends JFrame{
  private JTextFieldWatcher fieldsWatcher = new JTextFieldWatcher();

  private JTextFieldWatched textField1;
  private JTextFieldWatched textField2;
  private JTextFieldWatched textField3;

  public MyComponent(){
   textField1 = new JTextFieldWatched ("",fieldsWatcher);
   textField2 = new JTextFieldWatched ("",fieldsWatcher);
   textField3 = new JTextFieldWatched ("",fieldsWatcher);
  }   

  public void iterateAllTextFields(){
    for (JTextField field : fieldsWatcher.getAllTextField()){
      String yourValue = field.getText();
    }    
  }
}

All code is written at the hand without IDE, so sorry if any mistake.