--- a/NEWS	Sat Dec 16 18:41:41 2017 -0800
+++ b/NEWS	Sun Dec 17 07:04:31 2017 -0800
@@ -69,6 +69,11 @@
  ** An initial implementation of alpha transparency has been made for
     patch and surface objects.  Printing to svg and pdf is supported.
 
+ ** ishandle now returns true for both graphics handle objects and
+    Java objects.  The latter change was made for Matlab compatibility.
+    Use ishghandle or isgraphics if it is important not to include Java
+    objects.
+
  ** The following statistical functions have been moved from core
     Octave to the statistics package available from Octave Forge.
 
@@ -92,6 +97,7 @@
       integral
       integral2
       integral3
+      isgraphics
       openvar
       quad2d
       repelem

--- a/doc/interpreter/genpropdoc.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/doc/interpreter/genpropdoc.m	Sun Dec 17 07:04:31 2017 -0800
@@ -1635,7 +1635,7 @@
 function s = getstructure (objname, base = [])
   hf = [];
   if (! strcmp (objname, "root"))
-    ## Use an improbable number to avoid ishandle to return true for 1
+    ## Use an improbable number to avoid ishghandle to return true for 1
     hf = figure (2265465, "visible", "off");
   endif
 
@@ -1705,7 +1705,7 @@
   def = get (h, field);
 
   ## Don't print default values for graphics handles
-  if (isscalar (def) && def != 0 && ishandle (def))
+  if (isscalar (def) && def != 0 && ishghandle (def))
     def = "";
   else
     if (ischar (def))

--- a/doc/interpreter/plot.txi	Sat Dec 16 18:41:41 2017 -0800
+++ b/doc/interpreter/plot.txi	Sun Dec 17 07:04:31 2017 -0800
@@ -1182,11 +1182,13 @@
 @code{surface}, @code{image}, and @code{light} objects.
 
 Graphics handles may be distinguished from function handles
-(@pxref{Function Handles}) by means of the function @code{ishandle}.
-@code{ishandle} returns true if its argument is a handle of a graphics object.
+(@pxref{Function Handles}) by means of the function @code{ishghandle}.
+@code{ishghandle} returns true if its argument is a handle of a graphics object.
 In addition, a figure or axes object may be tested using @code{isfigure} or
-@code{isaxes} respectively.  The test functions return true only if the
-argument is both a handle and of the correct type (figure or axes).
+@code{isaxes} respectively.  To test for a specific type of graphics handle,
+such as a patch or line object, use @code{isgraphics}.  The more specific test
+functions return true only if the argument is both a graphics handle and of the
+correct type (figure, axes, specified object type).
 
 The @code{whos} function can be used to show the object type of each currently
 defined graphics handle.  (Note: this is not true today, but it is, I hope,
@@ -1352,13 +1354,15 @@
 @cindex handle functions
 
 To determine whether a variable is a graphics object index, or an index
-to an axes or figure, use the functions @code{ishandle}, @code{isaxes}, and
-@code{isfigure}.
+to an axes or figure, use the functions @code{ishghandle}, @code{isgraphics},
+@code{isaxes}, and @code{isfigure}.
+
+@DOCSTRING(ishghandle)
+
+@DOCSTRING(isgraphics)
 
 @DOCSTRING(ishandle)
 
-@DOCSTRING(ishghandle)
-
 @DOCSTRING(isaxes)
 
 @DOCSTRING(isfigure)

--- a/libinterp/corefcn/graphics.cc	Sat Dec 16 18:41:41 2017 -0800
+++ b/libinterp/corefcn/graphics.cc	Sun Dec 17 07:04:31 2017 -0800
@@ -2913,13 +2913,13 @@
 }
 
 static bool
-is_handle (const graphics_handle& h)
+is_hghandle (const graphics_handle& h)
 {
   return h.ok ();
 }
 
 static bool
-is_handle (double val)
+is_hghandle (double val)
 {
   graphics_handle h = gh_manager::lookup (val);
 
@@ -2927,11 +2927,11 @@
 }
 
 static octave_value
-is_handle (const octave_value& val)
+is_hghandle (const octave_value& val)
 {
   octave_value retval = false;
 
-  if (val.is_real_scalar () && is_handle (val.double_value ()))
+  if (val.is_real_scalar () && is_hghandle (val.double_value ()))
     retval = true;
   else if (val.isnumeric () && val.isreal ())
     {
@@ -2940,7 +2940,7 @@
       boolNDArray result (handles.dims ());
 
       for (octave_idx_type i = 0; i < handles.numel (); i++)
-        result.xelem (i) = is_handle (handles(i));
+        result.xelem (i) = is_hghandle (handles(i));
 
       retval = result;
     }
@@ -3645,7 +3645,7 @@
 
       callbackobject = val;
     }
-  else if (is_handle (val))
+  else if (is_hghandle (val))
     {
       if (get_callbackobject ().ok ())
         cbo_stack.push_front (get_callbackobject ());
@@ -3661,7 +3661,7 @@
 {
   graphics_handle val (v);
 
-  if (octave::math::isnan (val.value ()) || is_handle (val))
+  if (octave::math::isnan (val.value ()) || is_hghandle (val))
     {
       currentfigure = val;
 
@@ -3819,7 +3819,7 @@
 {
   graphics_handle hax (val);
 
-  if (octave::math::isnan (hax.value ()) || is_handle (hax))
+  if (octave::math::isnan (hax.value ()) || is_hghandle (hax))
     currentaxes = hax;
   else
     err_set_invalid ("currentaxes");
@@ -10515,15 +10515,15 @@
 
 // ---------------------------------------------------------------------
 
-DEFUN (ishandle, args, ,
+DEFUN (ishghandle, args, ,
        doc: /* -*- texinfo -*-
-@deftypefn {} {} ishandle (@var{h})
+@deftypefn {} {} ishghandle (@var{h})
 Return true if @var{h} is a graphics handle and false otherwise.
 
 @var{h} may also be a matrix of handles in which case a logical array is
 returned that is true where the elements of @var{h} are graphics handles and
 false where they are not.
-@seealso{isaxes, isfigure}
+@seealso{isgraphics, isaxes, isfigure, ishandle}
 @end deftypefn */)
 {
   gh_manager::auto_lock guard;
@@ -10531,8 +10531,27 @@
   if (args.length () != 1)
     print_usage ();
 
-  return ovl (is_handle (args(0)));
-}
+  return ovl (is_hghandle (args(0)));
+}
+
+/*
+%!test
+%! hf = figure ("visible", "off");
+%! unwind_protect
+%!   assert (ishghandle (hf));
+%!   assert (! ishghandle (-hf));
+%!   ax = gca;
+%!   l = line;
+%!   assert (ishghandle (ax));
+%!   assert (! ishghandle (-ax));
+%!   assert (ishghandle ([l, -1, ax, hf]), logical ([1, 0, 1, 1]));
+%!   assert (ishghandle ([l, -1, ax, hf]'), logical ([1, 0, 1, 1]'));
+%! unwind_protect_cleanup
+%!   close (hf);
+%! end_unwind_protect
+
+%!assert (ishghandle ([-1 0]), [false true])
+*/
 
 static bool
 is_handle_visible (const graphics_handle& h)

--- a/scripts/geometry/voronoi.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/geometry/voronoi.m	Sun Dec 17 07:04:31 2017 -0800
@@ -68,7 +68,7 @@
 
   narg = 1;
   hax = NaN;
-  if (isscalar (varargin{1}) && ishandle (varargin{1}))
+  if (isscalar (varargin{1}) && ishghandle (varargin{1}))
     hax = varargin{1};
     if (! isaxes (hax))
       error ("voronoi: HAX argument must be an axes object");

--- a/scripts/gui/guidata.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/gui/guidata.m	Sun Dec 17 07:04:31 2017 -0800
@@ -39,7 +39,7 @@
     print_usage ();
   endif
 
-  if (! ishandle (h))
+  if (! ishghandle (h))
     error ("guidata: H must be a valid object handle");
   endif
   h = ancestor (h, "figure");

--- a/scripts/gui/guihandles.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/gui/guihandles.m	Sun Dec 17 07:04:31 2017 -0800
@@ -42,7 +42,7 @@
   endif
 
   if (nargin == 1)
-    if (! ishandle (h))
+    if (! ishghandle (h))
       error ("guidata: H must be a valid object handle");
     endif
     h = ancestor (h, "figure");

--- a/scripts/gui/private/__uiobject_split_args__.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/gui/private/__uiobject_split_args__.m	Sun Dec 17 07:04:31 2017 -0800
@@ -30,7 +30,7 @@
   offset = 1;
 
   if (! isempty (in_args))
-    if (ishandle (in_args{1}))
+    if (ishghandle (in_args{1}))
       parent = in_args{1};
       offset = 2;
     elseif (! ischar (in_args{1}))
@@ -48,7 +48,7 @@
     i = find (strcmpi (args(1:2:end), "parent"), 1, "first");
     if (! isempty (i) && length (args) >= 2*i)
       parent = args{2*i};
-      if (! ishandle (parent))
+      if (! ishghandle (parent))
         error ("%s: invalid parent handle.", who);
       endif
       args([2*i-1, 2*i]) = [];

--- a/scripts/gui/uibuttongroup.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/gui/uibuttongroup.m	Sun Dec 17 07:04:31 2017 -0800
@@ -64,7 +64,7 @@
 
 function hui = uibuttongroup (varargin)
 
-  if (nargin == 1 && ishandle (varargin{1})
+  if (nargin == 1 && ishghandle (varargin{1})
       && strcmpi (get (varargin{1}, "type"), "uibuttongroup"))
     error ("uibuttongroup: focusing not implemented yet");
   endif

--- a/scripts/gui/uicontrol.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/gui/uicontrol.m	Sun Dec 17 07:04:31 2017 -0800
@@ -100,7 +100,7 @@
 
 function hui = uicontrol (varargin)
 
-  if (nargin == 1 && ishandle (varargin{1})
+  if (nargin == 1 && ishghandle (varargin{1})
       && strcmpi (get (varargin{1}, "type"), "uicontrol"))
     error ("uicontrol: focusing not implemented yet");
   endif

--- a/scripts/gui/uiwait.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/gui/uiwait.m	Sun Dec 17 07:04:31 2017 -0800
@@ -71,7 +71,7 @@
       endif
       waitfor (waitfor_args{:});
     unwind_protect_cleanup
-      if (ishandle (h) && isprop (h, "__uiwait_state__"))
+      if (ishghandle (h) && isprop (h, "__uiwait_state__"))
         set (h, "__uiwait_state__", "none");
       endif
     end_unwind_protect

--- a/scripts/gui/waitbar.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/gui/waitbar.m	Sun Dec 17 07:04:31 2017 -0800
@@ -65,7 +65,7 @@
   endif
 
   ## Use existing waitbar if it still points to a valid graphics handle.
-  if (nargin == 1 && ishandle (curr_waitbar))
+  if (nargin == 1 && ishghandle (curr_waitbar))
     hf = curr_waitbar;
   else
     hf = false;
@@ -264,7 +264,7 @@
 %!              "createcancelbtn", "setappdata (gcbf,'interrupt', true)");
 %! for ii = 1:niter
 %!   ## Check cancel request
-%!   if (! ishandle (hf))
+%!   if (! ishghandle (hf))
 %!     break;
 %!   elseif (getappdata (hf, "interrupt"))
 %!     delete (hf);
@@ -292,7 +292,7 @@
 %!   pause (0.5);
 %! endfor
 %!
-%! if (ishandle (hf))
+%! if (ishghandle (hf))
 %!   delete (hf);
 %! endif
 

--- a/scripts/image/brighten.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/image/brighten.m	Sun Dec 17 07:04:31 2017 -0800
@@ -49,7 +49,7 @@
     m = colormap ();
     h = gcf ();
   else
-    if (ishandle (arg1))
+    if (ishghandle (arg1))
       h = arg1;
       m = get (h, "colormap");
     elseif (iscolormap (arg1))
@@ -70,7 +70,7 @@
   endif
 
   if (nargout == 0)
-    if (ishandle (h))
+    if (ishghandle (h))
       set (h, "colormap", m .^ gamma);
     else
       colormap (m .^ gamma);

--- a/scripts/miscellaneous/delete.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/miscellaneous/delete.m	Sun Dec 17 07:04:31 2017 -0800
@@ -55,7 +55,7 @@
       endfor
     endfor
 
-  elseif (isscalar (varargin) && all (ishandle (varargin{1}(:))))
+  elseif (isscalar (varargin) && all (ishghandle (varargin{1}(:))))
     ## Delete a graphics object.
     __go_delete__ (varargin{1});
 

--- a/scripts/miscellaneous/getappdata.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/miscellaneous/getappdata.m	Sun Dec 17 07:04:31 2017 -0800
@@ -38,7 +38,7 @@
     print_usage ();
   endif
 
-  if (! all (ishandle (h(:))))
+  if (! all (ishghandle (h(:))))
     error ("getappdata: H must be a scalar or vector of graphic handles");
   endif
 

--- a/scripts/miscellaneous/isappdata.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/miscellaneous/isappdata.m	Sun Dec 17 07:04:31 2017 -0800
@@ -34,7 +34,7 @@
     print_usage ();
   endif
 
-  if (! all (ishandle (h(:))))
+  if (! all (ishghandle (h(:))))
     error ("isappdata: H must be a scalar or vector of graphic handles");
   elseif (! ischar (name))
     error ("isappdata: NAME must be a string");

--- a/scripts/miscellaneous/rmappdata.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/miscellaneous/rmappdata.m	Sun Dec 17 07:04:31 2017 -0800
@@ -38,7 +38,7 @@
   endif
 
   h = h(:).';
-  if (! all (ishandle (h)))
+  if (! all (ishghandle (h)))
     error ("rmappdata: H must be a scalar or vector of graphic handles");
   elseif (! iscellstr (varargin))
     error ("rmappdata: NAME must be a string");

--- a/scripts/miscellaneous/setappdata.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/miscellaneous/setappdata.m	Sun Dec 17 07:04:31 2017 -0800
@@ -35,7 +35,7 @@
 function setappdata (h, varargin)
 
   h = h(:).';
-  if (! all (ishandle (h)))
+  if (! all (ishghandle (h)))
     error ("setappdata: H must be a scalar or vector of graphic handles");
   elseif (mod (numel (varargin), 2) != 0)
     error ("setappdata: NAME/VALUE arguments must occur in pairs");

--- a/scripts/plot/appearance/__clabel__.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/appearance/__clabel__.m	Sun Dec 17 07:04:31 2017 -0800
@@ -32,7 +32,7 @@
   xspacing = axpos(3) / (lims(2) - lims (1));
   yspacing = axpos(4) / (lims(4) - lims (3));
 
-  if (isscalar (hparent) && ishandle (hparent)
+  if (isscalar (hparent) && ishghandle (hparent)
       && strcmp (get (hparent, "type"), "hggroup"))
     x = get (hparent, "xdata");
     xmin = min (x(:));

--- a/scripts/plot/appearance/camlookat.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/appearance/camlookat.m	Sun Dec 17 07:04:31 2017 -0800
@@ -58,7 +58,7 @@
     if (isaxes (hh))
       hax = hh;
       hh = get (hax, "children");
-    elseif (all (ishandle (hh)))
+    elseif (all (ishghandle (hh)))
       hax = ancestor (hh, "axes");
       if numel (hax) > 1
         hax = unique ([hax{:}]);
@@ -77,7 +77,7 @@
   for i = 1:numel (hh)
     h = hh(i);
 
-    if (! ishandle (h))
+    if (! ishghandle (h))
       error ("camlookat: Inputs must be handles.");
     end
 

--- a/scripts/plot/appearance/clabel.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/appearance/clabel.m	Sun Dec 17 07:04:31 2017 -0800
@@ -73,7 +73,7 @@
     hparent = gca ();
   else
     arg = varargin{1};
-    if (isscalar (arg) && ishandle (arg)
+    if (isscalar (arg) && ishghandle (arg)
         && strcmp (get (arg, "type"), "hggroup"))
       try
         get (arg, "contourmatrix");

--- a/scripts/plot/appearance/legend.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/appearance/legend.m	Sun Dec 17 07:04:31 2017 -0800
@@ -118,7 +118,7 @@
 function [hleg, hleg_obj, hplot, labels] = legend (varargin)
 
   if (nargin > 0
-      && (! ishandle (varargin{1})
+      && (! ishghandle (varargin{1})
           || (strcmp (get (varargin{1}, "type"), "axes")
               && ! strcmp (get (varargin{1}, "tag"), "legend"))))
     [ca, varargin, nargin] = __plt_get_axis_arg__ ("legend", varargin{:});
@@ -135,13 +135,13 @@
   endif
 
   ## Special handling for plotyy which has two axes objects
-  if (ishandle (ca) && isprop (ca, "__plotyy_axes__"))
+  if (ishghandle (ca) && isprop (ca, "__plotyy_axes__"))
     plty = get (ca, "__plotyy_axes__");
-    if (isscalar (plty) && ishandle (plty))
+    if (isscalar (plty) && ishghandle (plty))
       ca = [ca, plty];
     elseif (iscell (plty))
       ca = [ca, plty{:}];
-    elseif (all (ishandle (plty)))
+    elseif (all (ishghandle (plty)))
       ca = [ca, plty(:).'];
     else
       error ("legend.m: This should not happen.  File a bug report.");
@@ -151,7 +151,7 @@
     ca = ca(sort (n));
   endif
 
-  if (nargin > 0 && all (ishandle (varargin{1})))
+  if (nargin > 0 && all (ishghandle (varargin{1})))
     kids = flipud (varargin{1}(:));
     varargin(1) = [];
   else
@@ -1169,13 +1169,13 @@
     endif
   endfor
 
-  if (ishandle (t1))
+  if (ishghandle (t1))
     set (t1, "deletefcn", "");
     delete (t1);
   endif
 
   for i = 1 : numel (hplots)
-    if (ishandle (hplots(i)) && strcmp (get (hplots(i), "type"), "line"))
+    if (ishghandle (hplots(i)) && strcmp (get (hplots(i), "type"), "line"))
       dellistener (hplots(i), "color");
       dellistener (hplots(i), "linestyle");
       dellistener (hplots(i), "linewidth");

--- a/scripts/plot/appearance/material.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/appearance/material.m	Sun Dec 17 07:04:31 2017 -0800
@@ -82,7 +82,7 @@
   h = [];
   if (nargout == 0)
     ## Check whether first argument is list of graphics handles.
-    if (all (ishandle (varargin{1})))
+    if (all (ishghandle (varargin{1})))
       h = varargin{1};
       varargin(1) = [];
     endif

--- a/scripts/plot/appearance/thetaticks.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/appearance/thetaticks.m	Sun Dec 17 07:04:31 2017 -0800
@@ -65,7 +65,7 @@
       endif
 
     case 2
-      if (! ishandle (varargin{1}))
+      if (! ishghandle (varargin{1}))
         error ("thetaticks: HAX must be a handle to an axes object");
       endif
       hax = varargin{1};

--- a/scripts/plot/appearance/whitebg.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/appearance/whitebg.m	Sun Dec 17 07:04:31 2017 -0800
@@ -66,7 +66,7 @@
   have_fig = false;
 
   if (nargin > 0)
-    if (all (ishandle (varargin{1})))
+    if (all (ishghandle (varargin{1})))
       h = varargin{1};
       have_fig = true;
       if (nargin == 2)

--- a/scripts/plot/draw/camlight.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/camlight.m	Sun Dec 17 07:04:31 2017 -0800
@@ -99,9 +99,9 @@
   ## specifying azimuth and a light handle object (also a numeric double).
   ## We don't worry about that.
   if (numel (varargin) > 0 && numel (varargin{1}) == 1
-      && ishandle (varargin{1}))
+      && ishghandle (varargin{1}))
     hl = varargin{1};
-    if (! ishghandle (hl, "light"))
+    if (! isgraphics (hl, "light"))
       error ("camlight: HL must be a handle to a light object");
     endif
     varargin(1) = [];

--- a/scripts/plot/draw/colorbar.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/colorbar.m	Sun Dec 17 07:04:31 2017 -0800
@@ -331,7 +331,7 @@
 function update_colorbar_cmap (hf, d, hi, vert, init_sz)
   persistent sz = init_sz;
 
-  if (ishandle (hf) && strcmp (get (hf, "type"), "figure")
+  if (ishghandle (hf) && strcmp (get (hf, "type"), "figure")
       && (isempty (gcbf ()) || strcmp (get (gcbf (), "beingdeleted"), "off")))
     clen = rows (get (hf, "colormap"));
     if (clen != sz)

--- a/scripts/plot/draw/isocolors.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/isocolors.m	Sun Dec 17 07:04:31 2017 -0800
@@ -94,7 +94,7 @@
   if (isnumeric (vp) && columns (vp) == 3)
     pa = [];
     v = vp;
-  elseif (ishghandle (vp, "patch"))
+  elseif (isgraphics (vp, "patch"))
     pa = vp;
     v = get (pa, "Vertices");
   else

--- a/scripts/plot/draw/isonormals.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/isonormals.m	Sun Dec 17 07:04:31 2017 -0800
@@ -92,7 +92,7 @@
   if (isnumeric (vp) && columns (vp) == 3)
     pa = [];
     v = vp;
-  elseif (ishghandle (vp, "patch"))
+  elseif (isgraphics (vp, "patch"))
     pa = vp;
     v = get (pa, "Vertices");
   else

--- a/scripts/plot/draw/plotmatrix.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/plotmatrix.m	Sun Dec 17 07:04:31 2017 -0800
@@ -121,7 +121,7 @@
     if (isaxes (hc) && strcmpi (get (hc, "beingdeleted"), "off"))
       parent = get (hc, "parent");
       ## If the parent is invalid or being deleted, then do nothing
-      if (ishandle (parent) && strcmpi (get (parent, "beingdeleted"), "off"))
+      if (ishghandle (parent) && strcmpi (get (parent, "beingdeleted"), "off"))
         delete (hc);
       endif
     endif

--- a/scripts/plot/draw/plotyy.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/plotyy.m	Sun Dec 17 07:04:31 2017 -0800
@@ -183,18 +183,18 @@
   addlistener (ax(2), "nextplot", {@update_nextplot, ax(1)});
 
   ## Store the axes handles for the sister axes.
-  if (ishandle (ax(1)) && ! isprop (ax(1), "__plotyy_axes__"))
+  if (ishghandle (ax(1)) && ! isprop (ax(1), "__plotyy_axes__"))
     addproperty ("__plotyy_axes__", ax(1), "data");
     set (ax(1), "__plotyy_axes__", ax);
-  elseif (ishandle (ax(1)))
+  elseif (ishghandle (ax(1)))
     set (ax(1), "__plotyy_axes__", ax);
   else
     error ("plotyy.m: This shouldn't happen.  File a bug report.");
   endif
-  if (ishandle (ax(2)) && ! isprop (ax(2), "__plotyy_axes__"))
+  if (ishghandle (ax(2)) && ! isprop (ax(2), "__plotyy_axes__"))
     addproperty ("__plotyy_axes__", ax(2), "data");
     set (ax(2), "__plotyy_axes__", ax);
-  elseif (ishandle (ax(2)))
+  elseif (ishghandle (ax(2)))
     set (ax(2), "__plotyy_axes__", ax);
   else
     error ("plotyy.m: This shouldn't happen.  File a bug report.");

--- a/scripts/plot/draw/reducepatch.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/reducepatch.m	Sun Dec 17 07:04:31 2017 -0800
@@ -181,7 +181,7 @@
     endif
   elseif (isscalar (arg1))
     patch_handle = arg1;
-    if (ishghandle (patch_handle, "patch"))
+    if (isgraphics (patch_handle, "patch"))
       vertices = get (patch_handle, "Vertices");
       faces = get (patch_handle, "Faces");
     else

--- a/scripts/plot/draw/shrinkfaces.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/draw/shrinkfaces.m	Sun Dec 17 07:04:31 2017 -0800
@@ -76,7 +76,7 @@
   colors = [];
   p = varargin{1};
 
-  if (isscalar (p) && ishandle (p) && nargin < 3
+  if (isscalar (p) && ishghandle (p) && nargin < 3
       && strcmp (get (p, "type"), "patch"))
     faces = get (p, "Faces");
     vertices = get (p, "Vertices");
@@ -134,7 +134,7 @@
 
   switch (nargout)
     case 0
-      if (ishandle (p))
+      if (ishghandle (p))
         ## avoid exceptions
         set (p, "FaceVertexCData", [], "CData", []);
         set (p, "Vertices", v, "Faces", f, "FaceVertexCData", c);

--- a/scripts/plot/util/__actual_axis_position__.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/__actual_axis_position__.m	Sun Dec 17 07:04:31 2017 -0800
@@ -26,7 +26,7 @@
 
 function pos = __actual_axis_position__ (h)
 
-  if (ishandle (h))
+  if (ishghandle (h))
     axis_obj = get (h);
   elseif (isstruct (h))
     axis_obj = h;

--- a/scripts/plot/util/__opengl_info__.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/__opengl_info__.m	Sun Dec 17 07:04:31 2017 -0800
@@ -78,7 +78,7 @@
 
   info = [];
 
-  if (ishandle (h) && strcmp (get (h, "renderer"), "opengl"))
+  if (ishghandle (h) && strcmp (get (h, "renderer"), "opengl"))
     vend = get (h, "__gl_vendor__");
     if (isempty (vend))
       return;

--- a/scripts/plot/util/__plt_get_axis_arg__.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/__plt_get_axis_arg__.m	Sun Dec 17 07:04:31 2017 -0800
@@ -31,7 +31,7 @@
   ## Look for a scalar which is a graphics handle but not the
   ## Root Figure (0) or an ordinary figure (integer).
   if (numel (varargin) > 0 && numel (varargin{1}) == 1
-      && ishandle (varargin{1}) && varargin{1} != 0 && ! isfigure (varargin{1}))
+      && ishghandle (varargin{1}) && varargin{1} != 0 && ! isfigure (varargin{1}))
     htmp = varargin{1};
     if (! isaxes (htmp))
       error ("%s: first argument must be axes handle", caller);
@@ -42,7 +42,7 @@
     endif
   ## Look for "parent"/axis prop/value pair
   elseif (numel (varargin) > 1 && ! isempty (parent))
-    if (parent < numel (varargin) && ishandle (varargin{parent+1}))
+    if (parent < numel (varargin) && ishghandle (varargin{parent+1}))
       htmp = varargin{parent+1};
       if (isaxes (htmp) && ! strcmp (get (htmp, "tag"), "legend"))
         h = htmp;

--- a/scripts/plot/util/ancestor.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/ancestor.m	Sun Dec 17 07:04:31 2017 -0800
@@ -61,7 +61,7 @@
     h = num2cell (h);
     for nh = 1:numel (h)
       while (true)
-        if (isempty (h{nh}) || ! ishandle (h{nh}))
+        if (isempty (h{nh}) || ! ishghandle (h{nh}))
           break;
         endif
         if (any (strcmpi (get (h{nh}, "type"), type)))

--- a/scripts/plot/util/copyobj.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/copyobj.m	Sun Dec 17 07:04:31 2017 -0800
@@ -44,9 +44,9 @@
   othertypes = {"line", "patch", "surface", "image", "text"};
   alltypes = [partypes othertypes];
 
-  if (! ishandle (horig) || nargin > 2)
+  if (! ishghandle (horig) || nargin > 2)
     print_usage ();
-  elseif (! ishandle (hparent))
+  elseif (! ishghandle (hparent))
     hparent = figure (fix (hparent));
   else
     for hp = hparent(:)'

--- a/scripts/plot/util/findobj.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/findobj.m	Sun Dec 17 07:04:31 2017 -0800
@@ -96,7 +96,7 @@
     n1 = 0;
   else
     if (! isempty (varargin{1}))
-      if (ishandle (varargin{1}(1)))
+      if (ishghandle (varargin{1}(1)))
         handles = varargin{1};
         n1 = 2;
       else

--- a/scripts/plot/util/hdl2struct.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/hdl2struct.m	Sun Dec 17 07:04:31 2017 -0800
@@ -31,7 +31,7 @@
 
 function s = hdl2struct (h)
 
-  if (nargin != 1 || ! ishandle (h))
+  if (nargin != 1 || ! ishghandle (h))
     print_usage ();
   endif
 

--- a/scripts/plot/util/hgsave.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/hgsave.m	Sun Dec 17 07:04:31 2017 -0800
@@ -65,7 +65,7 @@
     if (isempty (h))
       error ("hgsave: No current figure to save");
     endif
-  elseif (! (ishandle (h) && ischar (filename)))
+  elseif (! (ishghandle (h) && ischar (filename)))
     print_usage ();
   endif
 

--- a/scripts/plot/util/hold.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/hold.m	Sun Dec 17 07:04:31 2017 -0800
@@ -56,7 +56,7 @@
     varargin(1) = [];
     nargs = numel (varargin);
     hfig = ancestor (hax, "figure");
-  elseif (nargin > 0 && numel (varargin{1}) > 1 && ishandle (varargin{1}))
+  elseif (nargin > 0 && numel (varargin{1}) > 1 && ishghandle (varargin{1}))
     print_usage ();
   else
     hax = gca ();

--- a/scripts/plot/util/isaxes.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/isaxes.m	Sun Dec 17 07:04:31 2017 -0800
@@ -22,7 +22,7 @@
 ##
 ## If @var{h} is a matrix then return a logical array which is true where the
 ## elements of @var{h} are axes graphics handles and false where they are not.
-## @seealso{isaxes, ishandle}
+## @seealso{isaxes, ishghandle}
 ## @end deftypefn
 
 ## Author: jwe
@@ -33,7 +33,7 @@
     print_usage ();
   endif
 
-  hlist = ishandle (h);
+  hlist = ishghandle (h);
   retval = hlist;
 
   if (any (hlist))

--- a/scripts/plot/util/isfigure.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/isfigure.m	Sun Dec 17 07:04:31 2017 -0800
@@ -23,7 +23,7 @@
 ## If @var{h} is a matrix then return a logical array which is true where the
 ## elements of @var{h} are figure graphics handles and false where they are
 ## not.
-## @seealso{isaxes, ishandle}
+## @seealso{isaxes, ishghandle}
 ## @end deftypefn
 
 ## Author: jwe
@@ -34,7 +34,7 @@
     print_usage ();
   endif
 
-  hlist = ishandle (h);
+  hlist = ishghandle (h);
   if (any (hlist))
     retval(hlist) = strcmp (get (h(hlist), "type"), "figure");
   else

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/plot/util/isgraphics.m	Sun Dec 17 07:04:31 2017 -0800
@@ -0,0 +1,106 @@
+## Copyright (C) 2008-2017 David Bateman
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn  {} {} isgraphics (@var{h})
+## @deftypefnx {} {} isgraphics (@var{h}, @var{type})
+## Return true if @var{h} is a graphics handle (of type @var{type}) and false
+## otherwise.
+##
+## When no @var{type} is specified the function is equivalent to
+## @code{ishghandle}.
+## @seealso{ishghandle, ishandle}
+## @end deftypefn
+
+function retval = isgraphics (h, type = "")
+
+  if (nargin < 1 || nargin > 2)
+    print_usage ();
+  endif
+
+  if (nargin == 2 && (! ischar (type) || ! isrow (type)))
+    error ("isgraphics: TYPE must be a string");
+  endif
+
+  ## Octave has no Simulink equivalent so it is sufficient to call ishghandle.
+  retval = ishghandle (h);
+
+  if (nargin == 2 && any (retval))
+    typematch = strcmpi (get (h(retval), "type"), type);
+    retval(retval) = typematch;
+  endif
+
+endfunction
+
+
+%!test
+%! hf = figure ("visible", "off");
+%! unwind_protect
+%!   assert (isgraphics (hf));
+%!   assert (isgraphics (hf, "figure"));
+%!   assert (! isgraphics (-hf));
+%!   assert (! isgraphics (hf, "foo"));
+%!   l = line;
+%!   ax = gca;
+%!   assert (isgraphics (ax));
+%!   assert (isgraphics (ax, "axes"));
+%!   assert (! isgraphics (-ax));
+%!   assert (! isgraphics (ax, "foo"));
+%!   assert (isgraphics (l));
+%!   assert (isgraphics (l, "line"));
+%!   assert (! isgraphics (-l));
+%!   assert (! isgraphics (l, "foo"));
+%!   p = patch;
+%!   assert (isgraphics (p));
+%!   assert (isgraphics (p, "patch"));
+%!   assert (! isgraphics (-p));
+%!   assert (! isgraphics (p, "foo"));
+%!   s = surface;
+%!   assert (isgraphics (s));
+%!   assert (isgraphics (s, "surface"));
+%!   assert (! isgraphics (-s));
+%!   assert (! isgraphics (s, "foo"));
+%!   t = text;
+%!   assert (isgraphics (t));
+%!   assert (isgraphics (t, "text"));
+%!   assert (! isgraphics (-t));
+%!   assert (! isgraphics (t, "foo"));
+%!   i = image ([1]);
+%!   assert (isgraphics (i));
+%!   assert (isgraphics (i, "image"));
+%!   assert (! isgraphics (-i));
+%!   assert (! isgraphics (i, "foo"));
+%!   hg = hggroup;
+%!   assert (isgraphics (hg));
+%!   assert (isgraphics (hg, "hggroup"));
+%!   assert (! isgraphics (-hg));
+%!   assert (! isgraphics (hg, "foo"));
+%! unwind_protect_cleanup
+%!   close (hf);
+%! end_unwind_protect
+
+%!test
+%! assert (isgraphics ([-1 0]), [false true]);
+%! assert (isgraphics ([-1 0], "root"), [false true]);
+%! assert (isgraphics ([-1 0], "foobar"), [false false]);
+
+## Test input validation
+%!error isgraphics ()
+%!error isgraphics (1, 2, 3)
+%!error <TYPE must be a string> isgraphics (0, 1)
+%!error <TYPE must be a string> isgraphics (0, {1})

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/plot/util/ishandle.m	Sun Dec 17 07:04:31 2017 -0800
@@ -0,0 +1,69 @@
+## Copyright (C) 2017 Rik Wehbring
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn  {} {} ishandle (@var{h})
+## Return true if @var{h} is a handle to a graphics or Java object and false
+## otherwise.
+##
+## @var{h} may also be a matrix of handles in which case a logical array is
+## returned that is true where the elements of @var{h} are handles to graphics
+## or Java objects and false where they are not.
+##
+## Programming Note: It is often more useful to test for a specific object
+## type.  To determine if a handle belongs to a graphics object use
+## @code{ishghandle} or @code{isgraphics}.  To determine if a handle belongs
+## to a Java object use @code{isjava}.
+## @seealso{ishghandle, isgraphics, isjava}
+## @end deftypefn
+
+function retval = ishandle (h)
+
+  if (nargin != 1)
+    print_usage ();
+  endif
+
+  retval = ishghandle (h) | isjava (h);
+
+endfunction
+
+
+%!test
+%! hf = figure ("visible", "off");
+%! unwind_protect
+%!   assert (ishandle (hf));
+%!   assert (! ishandle (-hf));
+%!   ax = gca;
+%!   l = line;
+%!   assert (ishandle (ax));
+%!   assert (! ishandle (-ax));
+%!   assert (ishandle ([l, -1, ax, hf]), logical ([1, 0, 1, 1]));
+%!   assert (ishandle ([l, -1, ax, hf]'), logical ([1, 0, 1, 1]'));
+%! unwind_protect_cleanup
+%!   close (hf);
+%! end_unwind_protect
+
+%!assert (ishandle ([-1 0]), [false true])
+
+%!testif HAVE_JAVA; usejava ("jvm")
+%! jobj = javaObject ("java.lang.Double", 1.0);
+%! assert (ishandle (jobj));
+
+## Test input validation
+%!error ishandle ()
+%!error ishandle (1, 2)

--- a/scripts/plot/util/ishghandle.m	Sat Dec 16 18:41:41 2017 -0800
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,106 +0,0 @@
-## Copyright (C) 2008-2017 David Bateman
-##
-## This file is part of Octave.
-##
-## Octave is free software; you can redistribute it and/or modify it
-## under the terms of the GNU General Public License as published by
-## the Free Software Foundation; either version 3 of the License, or
-## (at your option) any later version.
-##
-## Octave is distributed in the hope that it will be useful, but
-## WITHOUT ANY WARRANTY; without even the implied warranty of
-## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-## GNU General Public License for more details.
-##
-## You should have received a copy of the GNU General Public License
-## along with Octave; see the file COPYING.  If not, see
-## <http://www.gnu.org/licenses/>.
-
-## -*- texinfo -*-
-## @deftypefn  {} {} ishghandle (@var{h})
-## @deftypefnx {} {} ishghandle (@var{h}, @var{type})
-## Return true if @var{h} is a graphics handle (of type @var{type}) and false
-## otherwise.
-##
-## When no @var{type} is specified the function is equivalent to
-## @code{ishandle}.
-## @seealso{ishandle}
-## @end deftypefn
-
-function retval = ishghandle (h, type = "")
-
-  if (nargin < 1 || nargin > 2)
-    print_usage ();
-  endif
-
-  if (nargin == 2 && (! ischar (type) || ! isrow (type)))
-    error ("ishghandle: TYPE must be a string");
-  endif
-
-  ## Octave has no Simulink equivalent so it is sufficient to call ishandle.
-  retval = ishandle (h);
-
-  if (nargin == 2 && any (retval))
-    typematch = strcmpi (get (h(retval), "type"), type);
-    retval(retval) = typematch;
-  endif
-
-endfunction
-
-
-%!test
-%! hf = figure ("visible", "off");
-%! unwind_protect
-%!   assert (ishghandle (hf));
-%!   assert (ishghandle (hf, "figure"));
-%!   assert (! ishghandle (-hf));
-%!   assert (! ishghandle (hf, "foo"));
-%!   l = line;
-%!   ax = gca;
-%!   assert (ishghandle (ax));
-%!   assert (ishghandle (ax, "axes"));
-%!   assert (! ishghandle (-ax));
-%!   assert (! ishghandle (ax, "foo"));
-%!   assert (ishghandle (l));
-%!   assert (ishghandle (l, "line"));
-%!   assert (! ishghandle (-l));
-%!   assert (! ishghandle (l, "foo"));
-%!   p = patch;
-%!   assert (ishghandle (p));
-%!   assert (ishghandle (p, "patch"));
-%!   assert (! ishghandle (-p));
-%!   assert (! ishghandle (p, "foo"));
-%!   s = surface;
-%!   assert (ishghandle (s));
-%!   assert (ishghandle (s, "surface"));
-%!   assert (! ishghandle (-s));
-%!   assert (! ishghandle (s, "foo"));
-%!   t = text;
-%!   assert (ishghandle (t));
-%!   assert (ishghandle (t, "text"));
-%!   assert (! ishghandle (-t));
-%!   assert (! ishghandle (t, "foo"));
-%!   i = image ([1]);
-%!   assert (ishghandle (i));
-%!   assert (ishghandle (i, "image"));
-%!   assert (! ishghandle (-i));
-%!   assert (! ishghandle (i, "foo"));
-%!   hg = hggroup;
-%!   assert (ishghandle (hg));
-%!   assert (ishghandle (hg, "hggroup"));
-%!   assert (! ishghandle (-hg));
-%!   assert (! ishghandle (hg, "foo"));
-%! unwind_protect_cleanup
-%!   close (hf);
-%! end_unwind_protect
-
-%!test
-%! assert (ishghandle ([-1 0]), [false true]);
-%! assert (ishghandle ([-1 0], "root"), [false true]);
-%! assert (ishghandle ([-1 0], "foobar"), [false false]);
-
-## Test input validation
-%!error ishghandle ()
-%!error ishghandle (1, 2, 3)
-%!error <TYPE must be a string> ishghandle (0, 1)
-%!error <TYPE must be a string> ishghandle (0, {1})

--- a/scripts/plot/util/ishold.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/ishold.m	Sun Dec 17 07:04:31 2017 -0800
@@ -38,7 +38,7 @@
     fig = gcf ();
     ax = get (fig, "currentaxes");
   else
-    if (! ishandle (h))
+    if (! ishghandle (h))
       error ("ishold: H must be an axes or figure graphics handle");
     endif
 

--- a/scripts/plot/util/isprop.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/isprop.m	Sun Dec 17 07:04:31 2017 -0800
@@ -40,7 +40,7 @@
 
   res = false (size (obj));
   for i = 1:numel (res)
-    if (ishandle (obj(i)))
+    if (ishghandle (obj(i)))
       try
         v = get (obj(i), prop);
         res(i) = true;

--- a/scripts/plot/util/linkprop.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/linkprop.m	Sun Dec 17 07:04:31 2017 -0800
@@ -62,7 +62,7 @@
 
   if (numel (h) < 2)
     error ("linkprop: H must contain at least 2 handles");
-  elseif (! all (ishandle (h(:))))
+  elseif (! all (ishghandle (h(:))))
     error ("linkprop: invalid graphic handle in input H");
   endif
 
@@ -97,7 +97,7 @@
   if (! recursion)
     unwind_protect
       recursion = true;
-      set (hlist(ishandle (hlist)), prop, get (h, prop));
+      set (hlist(ishghandle (hlist)), prop, get (h, prop));
     unwind_protect_cleanup
       recursion = false;
     end_unwind_protect
@@ -108,7 +108,7 @@
 function delete_linkprop (hlist, prop)
 
   for i = 1 : numel (hlist)
-    if (ishandle (hlist(i)))
+    if (ishghandle (hlist(i)))
       for j = 1 : numel (prop)
         dellistener (hlist(i), prop{j});
       endfor

--- a/scripts/plot/util/module.mk	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/module.mk	Sun Dec 17 07:04:31 2017 -0800
@@ -60,7 +60,8 @@
   %reldir%/hold.m \
   %reldir%/isaxes.m \
   %reldir%/isfigure.m \
-  %reldir%/ishghandle.m \
+  %reldir%/isgraphics.m \
+  %reldir%/ishandle.m \
   %reldir%/ishold.m \
   %reldir%/isprop.m \
   %reldir%/linkaxes.m \

--- a/scripts/plot/util/newplot.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/newplot.m	Sun Dec 17 07:04:31 2017 -0800
@@ -244,7 +244,7 @@
 %!   li2 = line (1:10, sin (1:10), "parent", hg2);
 %!   hold off;
 %!   newplot (hg2);
-%!   assert (ishandle (li0), false);
+%!   assert (ishghandle (li0), false);
 %!   assert (get (hax, "children"), hg1);
 %!
 %!   ## kids are preserved for hggroups
@@ -254,7 +254,7 @@
 %!
 %!   ## preserve objects
 %!   newplot (li1);
-%!   assert (ishandle (li1));
+%!   assert (ishghandle (li1));
 %!
 %!   ## kids are deleted for axes
 %!   newplot (hax);

--- a/scripts/plot/util/print.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/print.m	Sun Dec 17 07:04:31 2017 -0800
@@ -485,7 +485,7 @@
         h = setdiff (h, hnone);
         m = numel (props);
         for n = 1:numel (h)
-          if (ishandle (h(n)))
+          if (ishghandle (h(n)))
             ## Need to verify objects exist since callbacks may delete objects
             ## as the colors for others are modified.
             rgb = get (h(n), color_props{c});
@@ -507,14 +507,14 @@
       h = findall (opts.figure, "-property", "fontname");
       m = numel (props);
       for n = 1:numel (h)
-        if (ishandle (h(n)))
+        if (ishghandle (h(n)))
           if (! isempty (opts.font))
             props(end+1).h = h(n);
             props(end).name = "fontname";
             props(end).value = {get(h(n), "fontname")};
           endif
         endif
-        if (ishandle (h(n)))
+        if (ishghandle (h(n)))
           if (! isempty (opts.fontsize))
             props(end+1).h = h(n);
             props(end).name = "fontsize";
@@ -523,7 +523,7 @@
         endif
       endfor
       if (! isempty (opts.font))
-        set (h(ishandle (h)), "fontname", opts.font);
+        set (h(ishghandle (h)), "fontname", opts.font);
       endif
       if (! isempty (opts.fontsize))
         if (ischar (opts.fontsize))
@@ -537,7 +537,7 @@
         endif
         ## FIXME: legend child objects need to be acted on first.
         ##        or legend fontsize callback will destroy them.
-        hlist = h(ishandle (h));
+        hlist = h(ishghandle (h));
         haxes = strcmp (get (hlist, "type"), "axes");
         set (hlist(! haxes), "fontsize", fontsize);
         set (hlist(haxes), "fontsize", fontsize);
@@ -557,12 +557,12 @@
     if (isstruct (props))
       ## Restore figure position and units first
       for n = nfig:-1:1
-        if (ishandle (props(n).h))
+        if (ishghandle (props(n).h))
           set (props(n).h, props(n).name, props(n).value{1});
         endif
       endfor
       for n = numel (props):-1:(nfig + 1)
-        if (ishandle (props(n).h))
+        if (ishghandle (props(n).h))
           set (props(n).h, props(n).name, props(n).value{1});
         endif
       endfor

--- a/scripts/plot/util/private/__gnuplot_draw_axes__.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/private/__gnuplot_draw_axes__.m	Sun Dec 17 07:04:31 2017 -0800
@@ -40,11 +40,11 @@
   ## Set to false for plotyy axes.
   ymirror = true;
   if (isfield (axis_obj, "__plotyy_axes__"))
-    if (all (ishandle (axis_obj.__plotyy_axes__)))
+    if (all (ishghandle (axis_obj.__plotyy_axes__)))
       ymirror = false;
     else
       h = axis_obj.__plotyy_axes__;
-      h = h(ishandle (h));
+      h = h(ishghandle (h));
       h = h(isprop (h, "__plotyy_axes__"));
       rmappdata (h, "__plotyy_axes__");
     endif

--- a/scripts/plot/util/private/__gnuplot_draw_figure__.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/private/__gnuplot_draw_figure__.m	Sun Dec 17 07:04:31 2017 -0800
@@ -158,7 +158,7 @@
                 hlegend = [];
                 fkids = get (h, "children");
                 for j = 1 : numel (fkids)
-                  if (ishandle (fkids (j))
+                  if (ishghandle (fkids (j))
                       && strcmp (get (fkids (j), "type"), "axes")
                       && (strcmp (get (fkids (j), "tag"), "legend")))
                     udata = get (fkids (j), "userdata");

--- a/scripts/plot/util/rotate.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/rotate.m	Sun Dec 17 07:04:31 2017 -0800
@@ -42,7 +42,7 @@
     print_usage ();
   endif
 
-  is_h = ishandle (h);
+  is_h = ishghandle (h);
   if (is_h)
     ax_list = get (h, "parent");
     if (iscell (ax_list))

--- a/scripts/plot/util/saveas.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/saveas.m	Sun Dec 17 07:04:31 2017 -0800
@@ -69,7 +69,7 @@
     print_usage ();
   endif
 
-  if (! ishandle (h))
+  if (! ishghandle (h))
     error ("saveas: H must be a graphics handle");
   endif
   if (! ischar (filename))

--- a/scripts/plot/util/struct2hdl.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/struct2hdl.m	Sun Dec 17 07:04:31 2017 -0800
@@ -51,7 +51,7 @@
   elseif (! all (isfield (s, fields)))
     print_usage ();
   elseif (isscalar (p))
-    if (! ishandle (p))
+    if (! ishghandle (p))
       error ("struct2hdl: P is not a handle to a graphic object");
     endif
     if (any (strcmp (get (p).type, partypes)))

--- a/scripts/plot/util/subplot.m	Sat Dec 16 18:41:41 2017 -0800
+++ b/scripts/plot/util/subplot.m	Sun Dec 17 07:04:31 2017 -0800
@@ -232,7 +232,7 @@
         ## case anymore due to the deletion of previous children (due to
         ## "deletefcn" callback or for legends/colorbars that are deleted
         ## with their corresponding axes).
-        if (! ishandle (child))
+        if (! ishghandle (child))
           continue;
         endif
         if (strcmp (get (child, "type"), "axes"))
@@ -579,7 +579,7 @@
 %!   subplot (3,3,1);
 %!   assert (gca (), hax(1));
 %!   subplot (2,1,1);
-%!   assert (ishandle (hax),[false(1,6), true(1,3)]);
+%!   assert (ishghandle (hax),[false(1,6), true(1,3)]);
 %! unwind_protect_cleanup
 %!   delete (hf);
 %! end_unwind_protect
@@ -595,7 +595,7 @@
 %!   subplot ("position", [0.5 0.5 0.3 0.3]);
 %!   assert (gca (), h2);
 %!   subplot ("position", [0.5 0.5 0.3 0.2]);
-%!   assert (! ishandle (h2));
+%!   assert (! ishghandle (h2));
 %! unwind_protect_cleanup
 %!   delete (hf);
 %! end_unwind_protect
@@ -609,8 +609,8 @@
 %!   subplot (3,5,1, "align");
 %!   assert (gca (), h1);
 %!   subplot (3,2,1, "align");
-%!   assert (! ishandle (h1));
-%!   assert (! ishandle (h2));
+%!   assert (! ishghandle (h1));
+%!   assert (! ishghandle (h2));
 %! unwind_protect_cleanup
 %!   delete (hf);
 %! end_unwind_protect