PL/SQL and Java Swing interface

Question

Everybody in this forum knows that Oracle is the best database around
with many functionalities, stability, performance, etc. We also know
that PL/SQL is a great language to manipulate information directly
in the database with many built in functions, OOP capability,
transaction control, among other features. Today an application that
manipulates information, which needs user interface, requires components
to be developed using different technologies and normally running in
different servers or machines. For example, the interface is done using
a dynamic HTML generator like JSP, PHP, PL/SQL Web Toolkit, etc.
This page is executed in an application server like Oracle iAS or
Tomcat, just to name two, which in turn access a database like Oracle to
build the HTML. Also rich clients like Java applets require an intermediate
server to access the database (through servlets for example) although
it is possible to access the database directly but with security issues.
Another problem with this is that complexity increases a lot, many
technologies, skills and places to maintain code which leads to a greater
failure probability. Also, an application is constantly evolving, new
calculations are added, new tables, changed columns. If you have an
application with product code for example and you need to increase its
size, you need to change it in the database, search for all occurrences
of it in the middle-tier code and perhaps adjust interfaces. Normally
there is no direct dependency among the tier components. On another
issue, many application interfaces today are based on HTML which doesn't
have interactive capabilities like rich-client interfaces. Although it
is possible to simulate many GUI widgets with JavaScript and DHTML, it is
far from the interactive level we can accomplish in rich clients like
Java Swing, Flash MX, Win32, etc. HTML is also a "tag-based" language
originally created to publish documents so even small pages require
many bytes to be transmitted, far beyond of what we see on the screen.
Even in fast networks you have a delay time to wait the page to be
loaded. Another issue, the database is in general the central location
for all kinds of data. Most applications relies on it for security,
transaction and availability. My proposal is to use Oracle as the
central location for interface, processing and data. With this approach
we can create not only the data manipulation procedures in the database,
but procedures that also control and manage user interfaces. Having
a Oracle database as the central location for all components has many
advantages:
- Unique point of maintenance, backup and restore
- Integrated database security
- One language for everything, PL/SQL or Java (even both if desired)
- Inherited database cache, transaction and processing optimizations
- Direct access to the database dictionary
- Application runs on Oracle which has support for many platforms.
- Transparent use of parallel processing, clusters and future
background technologies
Regarding the interface, I already created a Java applet renderer
which receives instructions from the database on how to create GUI
objects and how to respond to events. The applet is only 8kb and can
render any Swing or AWT object/event. The communication is done
through HTTP or HTTPS using Oracles's MOD_PLSQL included in the Apache
HTTP server which comes with the database or application server (iAS).
I am also creating a database framework and APIs in PL/SQL to
create and manipulate the client interface. The applet startup is
very fast because it is very small, you don't need to download large
classes with the client interface. Execution is done "on-demand"
according to instructions received from the database. The instructions
are very optimized in terms of network bandwidth and based on preliminary
tests it can be up to 1/10 of a similar HTML screen. Less network usage
means faster response and means that even low speed connections will
have a good performance (a future development can be to use this in
wireless devices like PDAs e even cell phones, just an idea for now).
The applet can also be executed standalone by using Java Web Start.
With this approach no business code, except the interface, is executed
on the client. This means that alterations in the application are
dynamically reflected in the client, no need to "re-download" the
application. Events are transmitted when required only so network
usage is minimized. It is also possible to establish triggering
events to further reduce network usage. Since the protocol used is
HTTP (which is stateless), the database framework I am creating will
be responsible to maintain the state of connections, variables, locks
and session information, so the developer don't need to worry about it.
The framework will have many layers, from communication up to
application so there will be pre-built functions to handle queries,
pagination, lock, mail, log, etc. The final objective is to have a
rich client application integrated into the database with minimum
programming and maintenance requirements, not forgetting customization
capabilities. Below is a very small example of what can de done. A
desktop with two windows, each window with two fields, a button with an
image to switch the values, and events to convert the typed text when
leaving the field or double-clicking it. The "leave" event also has an
optimization to only be triggered when the text changes. I am still
developing the framework and adjusting the renderer but I think that all
technical barriers were transposed by now. The framework is still in
the early stages, my guess is that only 5% is done so far. As a future
development even an IDE can be created so we have a graphical environment
do develop applications. I am willing to share this with the PL/SQL
community and listen to ideas and comments.
Example:
create or replace procedure demo1 (
jre_version in varchar2 := '1.4.2_01',
debug_info in varchar2 := 'false',
compress_buffer in varchar2 := 'false',
optimize_buffer in varchar2 := 'true'
) as
begin
interface.initialize('demo1_init','JGR Demo 1',jre_version,debug_info,compress_buffer,optimize_buffer);
end;
create or replace procedure demo1_init as
begin
toolkit.initialize;
toolkit.create_icon('icon',interface.global_root_url||'img/switch.gif');
toolkit.create_internal_frame('frame1','Frame 1',50,50,300,136);
toolkit.create_label('frame1label1','frame1',10,10,50,20,'Field 1');
toolkit.create_label('frame1label2','frame1',10,40,50,20,'Field 2');
toolkit.create_text_field('frame1field1','frame1',50,10,230,20,'Field 1','Field 1',focus_event=>true,mouse_event=>true);
toolkit.create_text_field('frame1field2','frame1',50,40,230,20,'Field 2','Field 2',focus_event=>true,mouse_event=>true);
toolkit.set_text_field_event('frame1field1',toolkit.focus_lost_event,'demo1_set_upper',toolkit.get_text_method,'FIELD 1','false');
toolkit.set_text_field_event('frame1field2',toolkit.focus_lost_event,'demo1_set_upper',toolkit.get_text_method,'FIELD 2','false');
toolkit.set_text_field_event('frame1field1',toolkit.mouse_double_clicked_event,'demo1_set_lower',toolkit.get_text_method,'field 1','false');
toolkit.set_text_field_event('frame1field2',toolkit.mouse_double_clicked_event,'demo1_set_lower',toolkit.get_text_method,'field 2','false');
toolkit.create_button('button1','frame1',10,70,100,25,'Switch','Switch the values of "Field 1" and "Field 2"','S','icon');
toolkit.set_button_event('button1',toolkit.action_performed_event,'demo1_switch_fields(''frame1field1'',''frame1field2'')','frame1field1:'||toolkit.get_text_method||',frame1field2:'||toolkit.get_text_method);
toolkit.create_internal_frame('frame2','Frame 2',100,100,300,136);
toolkit.create_label('frame2label1','frame2',10,10,50,20,'Field 1');
toolkit.create_label('frame2label2','frame2',10,40,50,20,'Field 2');
toolkit.create_text_field('frame2field1','frame2',50,10,230,20,'Field 1','Field 1',focus_event=>true,mouse_event=>true);
toolkit.create_text_field('frame2field2','frame2',50,40,230,20,'Field 2','Field 2',focus_event=>true,mouse_event=>true);
toolkit.set_text_field_event('frame2field1',toolkit.focus_lost_event,'demo1_set_upper',toolkit.get_text_method,'FIELD 1','false');
toolkit.set_text_field_event('frame2field2',toolkit.focus_lost_event,'demo1_set_upper',toolkit.get_text_method,'FIELD 2','false');
toolkit.set_text_field_event('frame2field1',toolkit.mouse_double_clicked_event,'demo1_set_lower',toolkit.get_text_method,'field 1','false');
toolkit.set_text_field_event('frame2field2',toolkit.mouse_double_clicked_event,'demo1_set_lower',toolkit.get_text_method,'field 2','false');
toolkit.create_button('button2','frame2',10,70,100,25,'Switch','Switch the values of "Field 1" and "Field 2"','S','icon');
toolkit.set_button_event('button2',toolkit.action_performed_event,'demo1_switch_fields(''frame2field1'',''frame2field2'')','frame2field1:'||toolkit.get_text_method||',frame2field2:'||toolkit.get_text_method);
end;
create or replace procedure demo1_set_upper as
begin
toolkit.set_string_method(interface.global_object_name,toolkit.set_text_method,upper(interface.array_event_value(1)));
toolkit.set_text_field_event(interface.global_object_name,toolkit.focus_lost_event,'demo1_set_upper',toolkit.get_text_method,upper(interface.array_event_value(1)),'false');
end;
create or replace procedure demo1_set_lower as
begin
toolkit.set_string_method(interface.global_object_name,toolkit.set_text_method,lower(interface.array_event_value(1)));
toolkit.set_text_field_event(interface.global_object_name,toolkit.mouse_double_clicked_event,'demo1_set_lower',toolkit.get_text_method,lower(interface.array_event_value(1)),'false');
end;
create or replace procedure demo1_switch_fields (
field1 in varchar2,
field2 in varchar2
) as
begin
toolkit.set_string_method(field1,toolkit.set_text_method,interface.array_event_value(2));
toolkit.set_string_method(field2,toolkit.set_text_method,interface.array_event_value(1));
toolkit.set_text_field_event(field1,toolkit.focus_lost_event,'demo1_set_upper',toolkit.get_text_method,upper(interface.array_event_value(2)),'false');
toolkit.set_text_field_event(field2,toolkit.focus_lost_event,'demo1_set_upper',toolkit.get_text_method,upper(interface.array_event_value(1)),'false');
toolkit.set_text_field_event(field1,toolkit.mouse_double_clicked_event,'demo1_set_lower',toolkit.get_text_method,lower(interface.array_event_value(2)),'false');
toolkit.set_text_field_event(field2,toolkit.mouse_double_clicked_event,'demo1_set_lower',toolkit.get_text_method,lower(interface.array_event_value(1)),'false');
end;

Answer 1

Is it sound like Oracle Portal?
But you want to save a layer 9iAS.
Basically, that was the WebDB.(Oracle changed the name to Portal when version 3.0)
Over all, I agree with you.
>>Having a Oracle database as the central location for all components has many
>>advantages:
>>
>>- Unique point of maintenance, backup and restore
>>- Integrated database security
>>- One language for everything, PL/SQL or Java (even both if desired)
>>- Inherited database cache, transaction and processing optimizations
>>- Direct access to the database dictionary
>>- Application runs on Oracle which has support for many platforms.
>>- Transparent use of parallel processing, clusters and future
>>background technologies
I would like to build 'ZOPE' inside Oracle DB as a back-end
Using Flash MX as front-end.
Thomas Ku.