[Theory] A simple but hard question about OO programming

I was in my first class of OO programming (4th year of computer engineering in Valencia) and the professor gave us homework.
The homework was a simple question about OO programming (it is not about a specific language, though we are going to use Java in the practice sessions), we shall find an answer to it and discuss it in class the next day.
The question was:
"May classes also be objects?"
which can be said as:
"May classes be instances of an(other) classes?"
I hope that you, archers, can enlighten me in this question

tvale wrote:I believe an object is an instance of a class.
Yup, that's true. Let's see... An object is an instance of a class, so we can have a lot of objects coming from one class.
We can say an object is not a class because it has a state (think about a light, it has a state: on or off, but a class light is not on/off, because in a class we just describe the behavior that class should have.
But what we're asking here is if a class can have a state. I think it may refer to static properties about the objects.

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Question about the programming of a legend

Hello everybody,
I have a question about the programming of a waveform's legend. I
already asked here in this forum about the legend programming (03)
months ago.
I went satisfied but I ve just noticed that this code
(See Code old_legend_test.llb with main.vi as main function) operates a
little different from my expectances.
Therefore I have a new question and I want to know if it
is possible by labview programming to plot and show, on a waveform
chart, a signal with activ plot superior to zero (0) without to be
obliged to plot and show a signal with activ plot equal to zero (0) or
inferior to the desired activ plot.
I give you an example
of what I m meaning. I have by example 4 signals (Signal 0, 1, 2 and 3)
and each signal corresponds respectively to a channel (Chan1, Chan2,
Chan3, Chan4). I want to control the legend (activ plot, plot name and
plot color) programmatically. Is it possible with labview to plot signal
1 or 2 or 3 or (1, 3) or (2,3) or (1,2,3) or other possible combination
without to active the signal with the corresponding activ plot zero
(0)?
Let see the labview attached data
(new_legend_test.llb with main.vi as main function). When I try to
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understand why they have no effect on the legend of my waveform chart.
Could somebody explain me what I m doing wrong or show me how to get a
correct legend with desired plots? Thank by advance for your assistance.
N.B.
The
both attached data are saved with labview 2009.
Sincerly,PrinceJack
Attachments:
old_legend_test.llb ‏65 KB
new_legend_test.llb ‏65 KB

Hi
princejack,
Thanks for
posting on National Instruments forum.
The behavior
you have is completely normal. You can control the number of row displayed in
the legend and this rows are linked to the data you send to your graph. Thus,
if you have 3 arrays of data, let say chan1, chan2 and chan3, you can choose
which data you want to display in your graph using the property node (Active
plot and visible). But for the legend as you send 3 plots there is an array of
the plot name [chan1, chan2, chan3] and you can display 0, 1, 2 or 3 rows of
this array but you cannot control the order in this array! So, to be able to
change this array you have to only send data you need to you graph. I'm not
sure my explanations are clear so I have implemented a simple example doing
that.
Benjamin R.
R&D Software Development Manager
http://www.fluigent.com/
Attachments:
GraphLegend.vi ‏85 KB

Hello my company Favorites I would like to first thank you for this wonderful program I have a question about the program. How can I Arabization program In your response to the spread accept me thanks and respect

Hello my company Favorites I would like to first thank you for this wonderful program I have a question about the program. How can I Arabization program In your response to the spread accept me thanks and respect

Hi ,
You might want to refer the following link to find your serial number and activate your software .
Here is the link for the same.
https://helpx.adobe.com/x-productkb/global/find-serial-number.html
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Regards
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A Simpler, More Direct Question About Merge Joins

This thread is related to Merge Joins Should Be Faster and Merge Join but asks a simpler, more direct question:
Why does merge sort join choose to sort data that is already sorted? Here are some Explain query plans to illustrate my point.
SQL> EXPLAIN PLAN FOR
2 SELECT * FROM spoTriples ORDER BY s;
PLAN_TABLE_OUTPUT
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Now look at this plan:
SQL> EXPLAIN PLAN FOR
2 SELECT /*+ USE_MERGE(t1 t2) */ t1.s, t2.s
3 FROM spoTriples t1, spoTriples t2
4 WHERE t1.s = t2.s;
Explained.
PLAN_TABLE_OUTPUT
|   0 | SELECT STATEMENT       |              |    11M|   297M|       | 13019 (6)| 00:02:37 |
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|   5 |    INDEX FAST FULL SCAN| PKSPOTRIPLES |   998K|    12M|       | 1460 (3)| 00:00:18 |
Predicate Information (identified by operation id):
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Licensing questions are best addressed by visiting the Oracle store, or contacting a salesrep in your area
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Question 3 and 4 have obvious answers
3: Even if you could this is illegal
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Tnsping only establishes whether a listener is running and shouldn't be called from an application
Sybrand Bakker
Senior Oracle DBA

Question about DNS programing

hi, i am creating a DNS query message,
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Very simple and quick question about Arrays

Hi,
I have the following code to produce a student grades provessing system. I have got it to store data in the array, i just cant figure out how to add the integers from the row to produce a total. Thats all I want to do create a total from the 6 marks and add a percentage.
Any help would be greatly appreciated.
-------------CODE BELOW----------------------
import java.util.*;
public class newstudent1_2
public static void main (String[]args)
System.out.println ("-----------------------------------------------"); //Decorative border to make the welcome message stand out
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int total_mark;
int num_students;
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mark = new int[num_students][num_questions] ;
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System.out.println("Enter the Students ID");
String student_id;
student_id =kybd.next();
System.out.println("Student "+i);
for( int j=1; j<num_questions; j++)
System.out.println("Please enter a mark for question "+j);
mark[i][j]=kybd.nextInt();
System.out.print("id mark1 mark2 mark3 mark4 mark5 mark6 mark7 mark8");
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System.out.println();
for (int i=0; i<num_students; i++)
for( int j=0; j<num_questions; j++)
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System.out.println();
--------------END OF CODE---------------
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I had to do this same sort of thing for a school assignment but i didnt use an array.
import java.text.DecimalFormat;
import TurtleGraphics.KeyboardReader;
public class grade_avg
     public static void main(String[] args)
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}output looks like:
Please enter a grade: 100
Please enter a grade: 50
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Want to upgrade to Mountain Lion, but CS6 questions about Auto-Save need answers...

Hi,
I'm on Mountain Lion for all my "non-critical" work, but I'm still running the latest Snow Leopard on my main desktop machine, running CS6 Design & Web Premium. I've avoided the switch primarily because of the auto-save feature that Apple placed into ML. I haven't found a satisfactory answer anywhere on the web to this basic question...is auto-save a problem, as Apple implements it, with CS6 and working on images?
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So, in other words, photoshops behavior works the same, using save as..., etc. as it did under Snow Leopard? I should expect the auto-save behavior that occurs in apps like iPhone, etc., where i can actually lose the original because of the constant backups, etc.?
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Simple, but dumb, question

My wife wants to copy a cassette tape to her G4 laptop. Is GarageBand the right application to digitize an analog source? I looked at the Apple page on GarageBand and didn't see anything that helped.
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You can use simpler programs than GB, but GB will do it:
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Simple but necessary question

I have noticed my computer fans running more so when the unit is hooked up to the internet WITHOUT any extra applications running (i.e. Safari)as when unpluged yet running with the same CPU demands.
In other words:
When I'm at work, (no internet hook up), and the computer is sitting idle but not asleep, the fans hardly kick in, yet, in the same situation, but at home HOOKED to Cable Net but still running idle, the fans kick in every once in a while.
Is this to be expected?

neuroanatomist
thank you again for the prompt answer.
As far as I can recall, I did the diagnostic you recommended with the activity monitor and nothing appeared too extensive.
I think I will attempt it again and hopefully, either find my answer, or ask for your advice again if negative.
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SOS!! Simple yes/no question about JPA...

Hello,
I have the following environment and requirements:
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-Latest version of Hibernate
-JSF 1.1
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-I must use the query cache and the second-level cache
My question is as follows:
What is the best solution?
Solution 1.
ONE EntityManagerFactory stored in the ServletContext for use by all of my web app users generating MULTIPLE INSTANCES of EntityManagers. (would this allow me to use the query cache?)
Solution 2.
ONE EntityManagerFactory and ONE EntityManager stored in the ServletContext for use by all of my web app users.
Thanks in advance,
Julien.

Regarding caching, what exactly are you referring to
by "query cache"? Are you saying you
plan to execute the same query multiple times but
you'd like the underlying persistence manager
to avoid trips to the actual database? Whether the
query is executed by an actual database
access or is fulfilled through some JVM-local cache
is not controlled by the spec. Most implementations
do allow for such caching but the behavior is
persistence-provider specific.Yes. I am actually using hibernate behind the scenes as my persistence framework.
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year's JavaOne called "Persistence In the
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Ctrl- T works fine but some questions about tweaking

1) Is it possible to change the number displayed (9)?
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I presently use my Favorites Bar and Groups as needed. I like the ease of use of Ctrl-T and was wondering.
I did try searching Help but nothing is broken. I'll keep trying though.
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hello DrDOS, in fact it will be possible in the next version, firefox 17, to change the number of thumbnails shown (one can enter '''about:config''' into the location bar & tweak the preferences browser.newtabpage.columns & browser.newtabpage.rows). if you want you can [https://www.mozilla.org/firefox/beta/ download the beta version] which already includes the feature.
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[[New Tab Page – show, hide and customize top sites]]

Simple but elusive question

I have a master/detail form. Upon updating a row in the detail block, I need to update a table which is different from both the master and detail tables. so far the insert and delete operations are working fine (I use post_insert and post_delete), but the problem is when I try to do an update because the pre_update and post_update triggers deal with the new value for the updated row. How can I handle the situation where there is an old/new value?

The best way to handle something on a table where you need the old and the new-values would be a database-trigger. Also for reasons of data-consistency a database-trigger would be the better solution (its always executed, not just for dml coming form a specific forms-module).
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Use a PRE-UPDATE-trigger and read the data directly from the db-tables via a select.

Help with a simple but crazymaking question!

hi there, would anyone here mind looking at my test site and
telling me what I am doing wrong?
http://presentations.patrickmeyers.com/
I am VERY new at anything web related, and trying to learn
some Dreamweaver, html, and css. Basically I want ALL my content
(which for now is just images) to stay flush left with each other
no matter what the user does with their web browser window. But
when I expand my web broswer window, two of my images (one of which
is a rollover image that I need to add a hyperlink to) bump over to
the right and up. I don't want them to do that! I want them to stay
flush left at all times.
I also want to center everything so that no matter what a
person does with their browser, the page stays in the center of the
window (i.e. the Yahoo homepage) but all the content remains left
aligned relative to the top.
I've tried every concievable setting in Dreamweaver I can
think of and nothing works. The button and bottom banner still move
over to the right and up.
Any tips? Thank you in advance!!!!!
p

<p><img src="banner.jpg" width="792" height="336"
align="left" /><a href="#"
onmouseout="MM_swapImgRestore()"
onmouseover="MM_swapImage('Image3','','click-button-yellow.jpg',1)"><img
src="click-button-purple.jpg" name="Image3" width="180"
height="46"
hspace="16" vspace="15" border="0" align="left" id="Image3"
/></a></p>
<p><img src="lowerbanner.jpg" width="792"
height="41" vspace="30"
align="left" /></p>
</body>
You have two elements horizontally adjacent (the banner image
at 792px
width, and the anchor tag at 180px width). Their combined
width is
792+180+32px = 1004px (the 32px comes from the hspace="16"
attribute). When
the browser viewport is less than 972px wide, the anchor tag
and its
associated image will just drop below the banner image (since
they are
contained in a <p> that has no explicit width).
Change this -
<p><img src="banner.jpg" width="792" height="336"
align="left" /><a href="#"
onmouseout="MM_swapImgRestore()"
onmouseover="MM_swapImage('Image3','','click-button-yellow.jpg',1)"><img
src="click-button-purple.jpg" name="Image3" width="180"
height="46"
hspace="16" vspace="15" border="0" align="left" id="Image3"
/></a></p>
to this -
<p style="width:1004px;"><img src="banner.jpg"
width="792" height="336"
align="left" /><a href="#"
onmouseout="MM_swapImgRestore()"
onmouseover="MM_swapImage('Image3','','click-button-yellow.jpg',1)"><img
src="click-button-purple.jpg" name="Image3" width="180"
height="46"
hspace="16" vspace="15" border="0" align="left" id="Image3"
/></a></p>
and see what happens.
> I also want to center everything so that no matter what
a person does with
> their browser, the page stays in the center of the
window (i.e. the Yahoo
> homepage) but all the content remains left aligned
relative to the top.
It depends on whether you are using absolute positioning on
the page, as to
which method might be best, but in either event, this will
work -
Change this -
</head>
to this -
<style type="text/css">
#wrapper { width:1004px; margin:0 auto;position:relative; }
/* 760px will display on an 800px screen maximized browser
window without */
/* horizontal scrollbars. 1004px is pretty wide, and will
display horizontal
scrollbars on 1024 screens.*/
</style>
</head>
change this -
<body
onload="MM_preloadImages('click-button-yellow.jpg')">
(the ellipsis represents any other attributes that might be
mentioned in the
body tag, and SHOULD NOT BE INCLUDED EXPLICITLY!)
to this -
<body
onload="MM_preloadImages('click-button-yellow.jpg')">
<div id="wrapper">
and this -
</body>
to this -

</div>
</body>
and see if that helps.
Murray --- ICQ 71997575
Adobe Community Expert
(If you *MUST* email me, don't LAUGH when you do so!)
==================
http://www.projectseven.com/go
- DW FAQs, Tutorials & Resources
http://www.dwfaq.com - DW FAQs,
Tutorials & Resources
==================
"patrickpmm" <[email protected]> wrote in
message
news:[email protected]...
> hi there, would anyone here mind looking at my test site
and telling me
> what I
> am doing wrong?
>
http://presentations.patrickmeyers.com/
>
> I am VERY new at anything web related, and trying to
learn some
> Dreamweaver,
> html, and css. Basically I want ALL my content (which
for now is just
> images)
> to stay flush left with each other no matter what the
user does with their
> web
> browser window. But when I expand my web broswer window,
two of my images
> (one
> of which is a rollover image that I need to add a
hyperlink to) bump over
> to
> the right and up. I don't want them to do that! I want
them to stay flush
> left
> at all times.
>
> I also want to center everything so that no matter what
a person does with
> their browser, the page stays in the center of the
window (i.e. the Yahoo
> homepage) but all the content remains left aligned
relative to the top.
>
> I've tried every concievable setting in Dreamweaver I
can think of and
> nothing
> works. The button and bottom banner still move over to
the right and up.
>
> Any tips? Thank you in advance!!!!!
> p
>

Really easy, but confusing question about SW installation.....

Hello:
I have a pc desktop (Win XP Home SP 2) and a new HP wireless laptop I want to connect with my new WRT54GS.
Question.....When I open the box, it says "STOP - LOAD THE CD FIRST".
Ok, fine. Load the cd where????? Desktop (wired to router), laptop, or both?????
Thanks for answering a silly question.
William Hollingsworth

Is your PC going to be wired or wireless? Anyway, set-up CD usually does not work properly. Connect a PC directly to the modem and go to www.linksys.com/easy and run the EasyLink Connect Tool.

Pretty simple but annoying question for newbie

when opening form is there a way to automatically display the
record rather than having to hit F8.
also....
is there a way to navigate through records using PL/SQL rather
than using the buttons on the tool bar at the top or form
runtime.
thanks in advance

This is probably in the wrong forum. ;)
Anyway, here's my suggestions for your two queries:
Q1) Add a WHEN-NEW-FORM-INSTANCE trigger containing the
following statement:
EXECUTE_QUERY ;
Q2) Use the up and down arrow keys - they navigate between the
previous and next records respectively.
HTH

[Theory] A simple but hard question about OO programming

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