| Allegro CL version 10.1 Unrevised from 10.0 to 10.1. 10.0 version |
Arguments: object event handler &key data count
object, the first argument, may be a remote Java
reference object used to specialize the Lisp method.
object may be nil
to
denote an event not associated with an object.
The value of the handler argument should be a
function which will be the handler for the
event. The form of the function is given below.
handler may be nil
to
delete a handler.
The data argument is any Lisp value. It is passed to the handler function as the first argument in each call.
The count argument may be an integer that
specifies the lifetime of the handler or nil
.
A nil
value specifies a handler that will
persist until deleted. A positive integer is decremented after each
call. When the value reaches zero, the handler is deleted. For
example, a count of 1 defines a handler that will
handle one event and then will disappear.
Note that only one handler may be specified for each event and object combination. A new handler definition simply overrides an existing one.
A handler function should have an argument list:
Arguments: data object longs strings event seqnum
The arguments to the event handler are the data and object that were used in the call to jregister-handler. The third argument is a sequence of integer values representing the numeric data associated with the event. The fourth argument is a sequence of strings representing the string data associated with the event. The event name is passed so that several events could share the same handler. The seqnum argument is the sequence number assigned to the event by the Java event handler. It may be used to identify events or detect lost events.
The handler functions are called sequentially in a dedicated Lisp
process; any Lisp errors during a call are ignored. If
*jlinker-verbose*
is
non-nil
(or if jlinker-init was called with a
non-nil
value for
the verbose keyword argument) then a message is
printed to the Lisp console when a handler function signals an error.
See jlinker.htm for more information on the jLinker facility.
Copyright (c) 1998-2022, Franz Inc. Lafayette, CA., USA. All rights reserved.
This page was not revised from the 10.0 page.
Created 2019.8.20.
| Allegro CL version 10.1 Unrevised from 10.0 to 10.1. 10.0 version |