What is an empty constructor?

Hi.
This might be a dumb question but I need to know what is an empty constructor?
I've checked my Murach and there is nothing mentioned.
Thank you.

jverd wrote:
In fact, I'm pretty sure the compiler puts the bytecodes for a super(); call into your class file just as if you had explicitly written it in the constructor body.Yes that is what the Sun compiler does.
I was also curious what exactly what the specification says about what it should do.
If it is required to do the code insertion then there should be a verification rule. I certainly couldn't find one.
I did find the following in both the JLS and the VM Spec in the "Creation of New Class Instances" sections.
+"This constructor does not begin with an explicit constructor invocation of another constructor in the same class (using this). If this constructor is for a class other than Object, then this constructor will begin with an explicit or _implicit_ invocation of a superclass constructor (using super). "+
That would suggest that a compiler is free to leave it out and then the VM would be responsible for calling the parents ctor. It doesn't even say which ctor it must call in that case, so presumably the VM could use a best match algorithm based on the current ctors parameters.

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Does class Exception have an empty constructor

I thought every class you create in Java automatically creates an empty constructor regardless if you put one or not. I have a piece a class that extends Exception. In order to create a new object of my class using an empty constructor, I have to create it myself, unless I can call Exception's empty constructor.

A default empty constructor will be added to any class in which you don't declare your own constructor. See http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#16823
If the body of a constructor does not start with a call to another constructor, via super() or this(), the compiler will automatically add a call to super() at the start of the constructor. See http://java.sun.com/docs/books/jls/second_edition/html/classes.doc.html#78435
I'm guessing you have your own Exception class that has a declared constructor like:
public class MyException extends Exception {
public MyException(String message) {
    super(message);
}You'll need to add your own empty constructor to this which calls super():
public class MyException extends Exception {
public MyException() {
    super();
public MyException(String message) {
    super(message);
}

Empty Constructor !!

Consider the following piece of code.... defined in a file untitled.java.
class test
test (String s)
test()
public class untitled extends test
untitled(String arg)
super (arg);
untitled (int a)
System.out.println("in constructor untitled int" + a);
public static void main(String args[])
Why is it mandatory to define the empty constructor in class test.??
If not defined then we get a compiler error indicating the constructor test() not defined....

untitled (int a)
System.out.println("in constructor untitled int"
int" + a);
Why is it mandatory to define the empty constructor in
class test.??Because
untitled(int a)
    System.out.println("in counstructor untitled int" + a);
Is equvalent to
untitled(int a)
    super();
    System.out.println("in counstructor untitled int" + a);
}If you do not explicitly call a superclass constructor or another constructor in the class, using super(...) or this(...) as the first statement in your constructor, then the compiler will automatically insert a call to super(); as the first statement.

How do I write an excel file and check what the next empty column would be to put the data in?

I have somehow managed to write the portion of labview that prompts the user for a name. It checks a file to see if they are a new user or not and then assigns a number if they are. The program then acquires data that is to be put into a spreadsheet. Each subject will have ten trials which will have three columns. How do I get the information into the columns and then check each time to see which column it should go into (i.e. the next empty column for that subject). I have attached what I have thus far. I wrote this a long time ago and haven't touched it for some time so everything is a blur.
Attachments:
promptForSwimmerName.vi ‏76 KB
Swimmers.dat ‏1 KB
Main__dummy.vi ‏28 KB

To perform those operations in excel you will use ActiveX. I will attach some examples of using Excel in LabVIEW and you can use these to do exactly what you want.
These three examples show how to manipulate properties, write to excel and read from excel. Let me know if there is more I can do.
Allan S.
Applications Engineering
National Instruments
Attachments:
BorderExample.vi ‏102 KB
ActiveX_write_Rows_To_Excel2000.vi ‏90 KB
ReadExample.vi ‏80 KB

Satellite A500-1GH What is a empty PCI slot with JGPS sign

Almost a year ago I bought a Toshiba Satellite A500-1GH.
I cannot say that I am not satisfied with the computer or the company.
The problems that I had was the Display problem (stop working for seconds) which was software problem (updated nVidia 8.16.11.8875) and with the HDD which stop working but company changed with a new one.
Now I wanted to upgrade the second memory module from 2GB to 4GB so I can have 2x4GB, but when I opened the memory compartment, I saw next to them an empty PCI slot with the sign JGPS.
Does anybody know what that is?
And if yes what is the part number?
Thank you in advance.

Hi mate
As far as I know JGPS is an GPS connector.
Possibly this connector would be shared by 3G miniPCI card.
As far as I know this Satellite A500-1GH has not been equipped with an 3G module and therefore the miniPCI slot is empty.
> And if yes what is the part number?
I don't know the part number but all parts can be ordered from local Toshiba ASP

What does this empty error box in iPhoto 11 mean (other than the QA on this app is non-existent)

Barnd new MBP OOB experience. More iPhoto issues. This time I tried to email a photo to a friend from within iPhoto. When I hit send I got the following error. (Tried to attach photo of empty error dialog box but to no avail.) So you will have to take my word that I got a pop up box with what appears to be an iPhoto error icon and no text.) Any idea what it means other than iPhoto continues to be the shoddiest app in the mac portfolio from a QA perspective???

Repaired Permissions. Same Dialog box. Can't email from within iPhoto on new MBP.
Why was I using it? Because that was my OOB experience with the new MBP.
Also I didn't realize I could use Image Capture with my iPhone. Image Capture is not available as a choice in iTunes. But perhaps that's what is meant by sync with a folder which I am now doing.
If so then correct, its not compulsory nor is it needed and now it has been eliminated.

Outlook today shows what looks like empty inbox

I have been using 2007 for ever and rely heavily on outlook today. A few weeks ago I logged into my work/exchange account
and outlook today was gone and replaced with what looked like an empty inbox screen. After some research we figured out that the res://C:\Program Files\Microsoft Office\OFFICE11\1033\outlwvw.dll/outlook.htm was missing. I have made several attempts to add
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We also tried to upgrade to 2010 with the same result. Interesting I created a new folder in the navigator and called it today
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Also to complicate things even more if I open in safe mode outlook today opens fine but will not allow me to save any changes.
I have disabled all add ins.

Can you post them in the outlook category for much faster response ..
http://social.technet.microsoft.com/Forums/en-US/home?forum=outlook
Exchange Queries

What is an "empty restriction formula"?

Users are getting a popup window when opening some of the (ALCM imported) Web Analysis documents. (11.1.2.2)"
The popup contains a message:
"The empty restriction formula has been removed.
If they (or I) click OK and save the document the message is "gone for ever". So thats good news.
But I do not understand what the message is refering to. I guess its a essbase message, but perhaps you can help m clarify matters.
Thanks in advance
Detlev

In previous Web Analysis releases (up to 11.1.1.3) it was possible to add a "Restrict Data" definition with empty restrict formula body.
For the latest releases, there was a bug request that WA should automatically remove the empty "Restrict Data" definitions from the reports created in previous product releases.
So it recommended to show a warning to end users notifying them about invalid "Restrict Data" DTO removal.
Implementation for removing empty Restrict Data was added with additional notification "The empty restriction formula has been removed".

X200 What is the empty hole next to the closing clip ?

Hello!
I have a question about the empty hole next to the clip where i clips the screen when you close it. To my guess is a 5-1 reader because i also have a modem port . My question is , is it normal that there is an empty hole with no casing inside? I mean there isn't a casing like for sd card or something , just an empty hole . What can i use it for since there is no casing for sd card? This is a picture i found from google , it looks like this
http://www.notebookreview.com/picture/?f=46844
Cheers
shak
Solved!
Go to Solution.

No need of removing anything. Just insert the SD card in the slot, (SD card brand should be on top) Insert it until you hear a "click".
Press it again to get it out.
Check the first 10 seconds of this video: http://www.youtube.com/watch?v=EG4OsFRZr5Q
/L40SX/240/240X/2*340CSE/360PE/365XD/380D/380E/380XD/380Z/390/560E/560X/2*570/2*600/600E/750Cs/755C/760CD/760EL/760XD/770E/A20p/A22p
A31/i1600/G40/R50p/R61i/S30/SL510/2*T22/4*T4x/11*T6x/6*T4x0x/6*T5x0/3*W5x0/W700/3*X2x/4*X3x/3*X4x/5*X6x/3*X6xT/10*X2xx/2*X200T/4*X30x/Z60m/3*Z61x
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What does the empty() method do exactly?

Any help appreciated, can't find it in here http://www.adobe.com/devnet-docs/edgeanimate/api/current/index.html - is there another doc i should be reading?

It's a jquery method, details found here
hth
Darrell.

What would an empty Doubly Linked List pictorially look like?

Would it just be the head and tail set to null? or do the they have to be linked?

It depends.
If you have head and tail nodes that don't hold data, but are just "anchors", then, yes, they'd point to each other. If your head and tail are just regular data nodes, then the references would be null.

What is = "constructor" in CS3 ?

Anyone know what the substitute for "constructor" is in CS3?
example (from O'reilly Shortcuts Guide):
if( app.selection[0].constructor.name == 'InsertionPoint' )
app.selection[0].contents = 'Words, my lord, words.';
The toolkit won't accept it. I know I'm blind. Any ideas?
Thanks in advance,
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Hi Seth,
...and you need to be certain that you've got InDesign selected as the target application in the ESTK.
Thanks,
Ole

Always create any Object even without default constructor?

hi!
i'm wondering if there's an easy way to construct an object of a given class?
let's assume i've got a class
class MyClass
public MyClass( OtherClass c)
}now when i get the constructors for its Class-object with
clazz.getDeclaredConstructor()
it will return null;
ok now i know ther's no default/empty constructor.
does it make sense to then search for the next constructor with n parameters?
and then invoke it with nonsense values?
what happens if the parameter classes also have no default constructor to create parameter objects? like this:
class OtherClass
public OtherClass ( MyClass c)
}now there's a loop between the two constructors and i can't create empty parameter values to invoke any of them!
i wonder how the serialization engine works then?
or did i miss something trivial (it's really late here ;) )

What's the problem? To create a MyClass object, you
don't need any OtherClass objects. You just do the
equivalent ofnew MyClass(null)in your
reflective code.
slap forehead with toilet
thanks for the tip.
as i said there was something absolutely easy, it's tough not seeing the forest for the trees ;/
But I agree with jschell, if your requirements are to
create objects of arbitrary classes and call
arbitrary methods with arbitrary parameter lists,
then whoever did your design didn't think for long
enough.WELL. you're absolutely right. but when it's time to process ANY given object there's no reliability on whatever design was chosen. or, would you insist the developer had to provide standatized formats when you write a debugger? no it has to work with any. so must i!

What's the real meaning of "JavaBean"

What's its real meaning?
Are HttpRequest,HttpResponse JavaBeans?

What's its real meaning?
Are HttpRequest,HttpResponse JavaBeans?No.
http://java.sun.com/products/javabeans/
JavaBeans are intended to be platform-independent reuseable program chunks. They require their methods to follow naming conventions so they can be universally recognized and applied.
HttpServletRequest, and HttpServletResponse are dependent on Servlets. They are also interfaces. JavaBeans are classes (so they can carry their implementation around with them). These classes do have some methods that follow the JavaBeans specification, but (their wrapper classes) do not provide public empty constructor, the first requirenment of a JavaBean.
Although they are not javabeans, you can use the methods that they have that follow the naming conventions (like request.getMethod() and request.getRequestURL() or response.isCommitted() and response.setContentType()) through JavaBeans mechanisms, like EL and JSTL - if you already have an instance of the objects you are working on (which you do in Servlets/JSP). You would not have access to their other - non spec. following - methods.

What is the difference between initialization initiation pls explain

**What is the difference between initialization initiation of object pls explain with example............**
WHAT is the default constructor..........

886152 wrote:
**What is the difference between initialization initiation of object pls explain with example............**There is no such thing in the official Java vernacular as "initiation."
WHAT is the default constructor..........[url http://java.sun.com/docs/books/jls/third_edition/html/classes.html#16823]JLS 8.8.9 Default Constructor says:
>
If a class contains no constructor declarations, then a default constructor that takes no parameters is automatically provided:
* If the class being declared is the primordial class Object, then the default constructor has an empty body.
* Otherwise, the default constructor takes no parameters and simply invokes the superclass constructor with no arguments.

What is an empty constructor?

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