ABCL - error trying to add component to JPanel - add not found

Question

I am trying to build a Java GUI using ABCL. However, it throws an error.

#<THREAD "interpreter" {67D71B82}>: Debugger invoked on condition of type JAVA-EXCEPTION
  Java exception 'java.lang.NoSuchMethodException: No applicable method named add found in javax.swing.JPanel'.
Restarts:
  0: ABORT     Return to debug level 1.
  1: TOP-LEVEL Return to top level.

My code is as follows:

(defconstant +jframe+ "javax.swing.JFrame")
(defconstant +jpanel+ "javax.swing.JPanel")
(defconstant +button+ "javax.swing.JButton")

(defconstant +flowLayout+ "java.awt.FlowLayout")
(defconstant +dimension+ "java.awt.Dimension")

(defun make-frame (name width height) 
   (let ((this (jnew +jframe+ name))
        (dims (jnew +dimension+ width height)))

        (jcall "setPreferredSize" this dims)
        this))

(defun make-panel ()
   (let ((this (jnew +jpanel+)))
       this))

(defun make-button (name)
    (let ((this (jnew +button+ name))
        this)))

(defun main ()
   (let ((frame (make-frame 
                   "This is my frame"
                   400 300))
         (panel (make-panel))
         (button1 (make-button
                   "Press me"))
         )

    (jcall "add" frame panel)  
    (jcall "add" panel button1 (jfield +flowLayout+ "LEFT"))   

    (jcall "pack" frame)
    (jcall "setVisible" frame t)

))

The error is on line (jcall "add" panel button1 (jfield +flowLayout+ "LEFT")). Commenting this out leads to a working application.

Answer 1

According to [1] you need to use jclass to get the java class objects for each of the parameters, and then jmethod to find the right overload, and then finally you can call jcall

1: https://armedbear.common-lisp.dev/doc/abcl-user.html