Add implement interface [#1 state:resolved]

TODO.txt

@@ -9,8 +9,6 @@ Short term
 - goto-type-at-point (with disassembly if needed)
   - create if necessary
 
-- Implement interface
-
 - Code generation
   - getters/setters
   - delegation

src/main/lisp/malabar-mode.el

@@ -634,6 +634,11 @@ in the list")
   (or (semantic-current-tag-of-class 'type)
       (car (semantic-find-tags-by-class 'type (current-buffer)))))
 
+(defun malabar-goto-start-of-class ()
+  (interactive)
+  (let ((class-tag (malabar-get-class-tag-at-point)))
+    (goto-char (semantic-tag-start class-tag))))
+
 (defun malabar-goto-end-of-class ()
   (interactive)
   (let ((class-tag (malabar-get-class-tag-at-point)))
@@ -754,9 +759,9 @@ in the list")
   (unless (bolp)
     (forward-line 1)))
 
-(defun malabar-prompt-for-and-qualify-class (&optional class)
+(defun malabar-prompt-for-and-qualify-class (prompt &optional class)
   (let* ((class (or class
-                    (read-from-minibuffer "Class to extend: ")))
+                    (read-from-minibuffer prompt)))
          (qualified-class (or (malabar-import-find-import class)
                               (malabar-qualify-class-name-in-buffer class)))
          (class-info (malabar-get-class-info qualified-class)))
@@ -769,25 +774,45 @@ in the list")
 (defun malabar-implement-interface (&optional interface)
   (interactive)
   (destructuring-bind (interface qualified-interface interface-info)
-      (malabar-prompt-for-and-qualify-class interface)
-    (unless (malabar--class-accessible-p qualified-interface interface-info)
-      (error "You cannot implement %s, it is not accessible from %s"
-             qualified-interface (malabar-get-package-name)))
+      (malabar-prompt-for-and-qualify-class "Interface to implement: " interface)
     (unless (malabar--interface-p interface-info)
       (error "You cannot implement %s, it is not an interface"
              qualified-interface))
-    ;; Move to correct insertion point
-    ;; insert "implements" and indent if first interface, insert ", " if not
-    (insert qualified-interface)
+    (unless (malabar--class-accessible-p qualified-interface interface-info)
+      (error "You cannot implement %s, it is not accessible from %s"
+             qualified-interface (malabar-get-package-name)))
+    (malabar--implement-interface-move-to-insertion-point)
+    (if (semantic-tag-type-interfaces (malabar-get-class-tag-at-point))
+        (insert ", ")
+      (unless (bolp)
+        (newline))
+      (insert "implements ")
+      (indent-according-to-mode))
+    (insert interface)
+    (when (malabar--get-type-parameters interface-info)
+      (insert (concat "<"
+                      (mapconcat #'identity (malabar--get-type-parameters interface-info)
+                                 ", ")
+                      ">")))
+    (unless (eolp)
+      (newline-and-indent))
     (mapc #'malabar-override-method (malabar--get-abstract-methods interface-info))))
 
+(defun malabar--implement-interface-move-to-insertion-point ()
+  (malabar-goto-start-of-class)
+  (skip-chars-forward "^{")
+  (when (semantic-tag-type-interfaces (malabar-get-class-tag-at-point))
+    (search-backward
+     (car (last (semantic-tag-type-interfaces (malabar-get-class-tag-at-point)))))
+    (goto-char (match-end 0))))
+
 (defun malabar-extend-class (&optional class)
   (interactive)
   (unless (equal "java.lang.Object" (malabar-get-superclass-at-point))
     (error "Java is limited to single inheritance, class already extends %s"
            (malabar-get-superclass-at-point)))
   (destructuring-bind (class qualified-class class-info)
-      (malabar-prompt-for-and-qualify-class class)
+      (malabar-prompt-for-and-qualify-class "Class to extend: " class)
     (when (equal qualified-class "java.lang.Enum")
       (error "You cannot extend %s, see the Java Language Specification" qualified-class))
     (unless (malabar--class-accessible-p qualified-class class-info)