An object variable and class name

How come some classes, such as wrapper classes, don?t use an object variable to call a method in their classes? For example, StingBuffer or String class needs an object variable to call its method but Double, Integer, Character, NumberFormat, or some other classes doesn?t use an object variable to call a method in its class. Why is that? Any suggestions? Any explanation would be helpful.

errr.. do you mean static methods and instance methods?
http://java.sun.com/docs/books/tutorial/java/javaOO/classvars.html

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Why java file name and class name are equal

could u explain why java file name and class name are equal in java

The relevant section of the JLS (?7.6):
When packages are stored in a file system (?7.2.1), the host system may choose to enforce the restriction that it is a compile-time error if a type is not found in a file under a name composed of the type name plus an extension (such as .java or .jav) if either of the following is true:
* The type is referred to by code in other compilation units of the package in which the type is declared.
* The type is declared public (and therefore is potentially accessible from code in other packages).
This restriction implies that there must be at most one such type per compilation unit. This restriction makes it easy for a compiler for the Java programming language or an implementation of the Java virtual machine to find a named class within a package; for example, the source code for a public type wet.sprocket.Toad would be found in a file Toad.java in the directory wet/sprocket, and the corresponding object code would be found in the file Toad.class in the same directory.
When packages are stored in a database (?7.2.2), the host system must not impose such restrictions. In practice, many programmers choose to put each class or interface type in its own compilation unit, whether or not it is public or is referred to by code in other compilation units.

Undefined variable or class name

I am trying to call a java class to another class but gets the error: "Undefined variable or class name"
Both my java files are in the same directory and I am able to compile only one of the program. Wondering what am I missing?
The source code is:
ServletUtilities.java: (I am able to compile)
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class ServletUtilities {
public static final String DOCTYPE =
     "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 " +
     "Transitional//EN\">";
public static String headWithTitle(String title) {
     return(DOCTYPE + "\n" +
          "<HTML>\n" +
          "<head><title>" + title + "</title></head>\n");
HelloWWW3.java (getting error when compile)
public class HelloWWW3 extends HttpServlet {
public void doGet(HttpServletRequest request,
               HttpServletResponse response)
     throws ServletException, IOException
     response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println(ServletUtilities.headWithTitle("Hello WWW") +
          "<body>\n" +
          "<h1>Hello WWW</h1>\n" +
          "</body></html>");

I tried and I got these errors:
C:\java servlets\HelloWWW3\src>javac -classpath . HelloWWW3.java
HelloWWW3.java:4: Package javax.servlet not found in import.
import javax.servlet.*;
^
HelloWWW3.java:5: Package javax.servlet.http not found in import.
import javax.servlet.http.*;
^
HelloWWW3.java:7: Superclass coreservlets.HttpServlet of class coreservlets.Hell
oWWW3 not found.
public class HelloWWW3 extends HttpServlet
^
3 errors
Then I moved HelloWWW3.java and ServletUtilities.class file to C:\jakarta-tomcat-3.2.3\lib
This dir has files
JAXP JAR
SERVLET JAR
ANT JAR
PARSER JAR
WEBSER~1 JAR
JASPER JAR
and compiled and got this error
C:\jakarta-tomcat-3.2.3\lib>javac -classpath . HelloWWW3.java
HelloWWW3.java:4: Package javax.servlet not found in import.
import javax.servlet.*;
^
HelloWWW3.java:5: Package javax.servlet.http not found in import.
import javax.servlet.http.*;
^
HelloWWW3.java:7: Superclass coreservlets.HttpServlet of class coreservlets.Hell
oWWW3 not found.
public class HelloWWW3 extends HttpServlet
^
3 errors
Here is what I hava defined for my CLASSPATH
C:\jakarta-tomcat-3.2.3\lib>echo %CLASSPATH%
C:\jakarta-tomcat-3.2.3\lib\servlet.jar;C:\jakarta-tomcat-3.2.3\lib\jasper.jar
------------------------------------------

Location of variable and function names in SWF bytecode?

Ok, so I'm looking at the specification PDF for v10 of a SWF file.
Here is a link to it: http://www.adobe.com/devnet/swf/pdf/swf_file_format_spec_v10.pdf
I can't find anything in there about where or how a SWF stores variable and function names in the bytecode, though SWF decompilers can find them in any SWF file. So they must be in there somewhere.
Can any one help me on this one?

Hi check the varaibles by giving ur tech.name of report input parameter to the below program,
RSRQ_QUERYDEFINITION
it will all the query details. So you can find ur varaibles where it is used exactly.
bhaskar

[svn] 2932: Updated manifests with recent changes to TCAL package and class names.

Revision: 2932
Author: [email protected]
Date: 2008-08-20 14:01:37 -0700 (Wed, 20 Aug 2008)
Log Message:
Updated manifests with recent changes to TCAL package and class names.
Reviewer: Jason
Bugs: SDK-16531
QA: No
Doc: No
Ticket Links:
http://bugs.adobe.com/jira/browse/SDK-16531
Modified Paths:
flex/sdk/trunk/frameworks/fxg-manifest.xml
flex/sdk/trunk/frameworks/mxml-2009-manifest.xml

Revision: 2932
Author: [email protected]
Date: 2008-08-20 14:01:37 -0700 (Wed, 20 Aug 2008)
Log Message:
Updated manifests with recent changes to TCAL package and class names.
Reviewer: Jason
Bugs: SDK-16531
QA: No
Doc: No
Ticket Links:
http://bugs.adobe.com/jira/browse/SDK-16531
Modified Paths:
flex/sdk/trunk/frameworks/fxg-manifest.xml
flex/sdk/trunk/frameworks/mxml-2009-manifest.xml

Where is the Package Name and Class Name for Android to Facebook SSO?

Where is the Package Name and Class Name for Android to Facebook SSO?
I am trying to fill these fields http://developers.facebook.com/docs/mobile/android/build/#ref for Facebook but i can't figure out what to place in Android Package Name and Andorid Class Name,
same thing for the Android Key Hash, I followed this guide http://www.skoobalon.com/blog/2012/06/13/getting-the-android-key-hash-for-facebook-from-an -air-app/ but I am not sure if it is the right thing to do.
I was thinking maybe the Pakage Name is air.com.myname.myappname (where com.myname.myappname is also the id used in the application.xml) and the Class name is air.com.myname.myappname.MyDocumentClass ?
Is there an official guide somewhere?
Also do you guys know if there is somewhere a library we can use within AIR to do SSO on Facebook from Andorid?

For what it's worth, I don't think a WiFi connection would be reliable enough. You wouldn't want your picture to freeze just because a neighbour has turned on their baby monitor. WiFi uses the same frequencies as a myriad of other devices, as well as all your neighbours' WiFi.

How to convert a String variable as class name and method name?

i have two classes
class Student
public String insertStudent(String sname)
{ return("Student has been inserted "); }
class Teacher
public String execute(String methodName, String className)
{ //return statement of the method 'insertStudent' in the class 'Student'; }
}Now, i have a class with the main method. Here, i would like to call the method *'insertStudent'* of class *'Student'*
using the method *'execute'* of class *'Teacher',* passing the method-name and the class-name (viz. insertStudent, Student) as the
String parameter.
Can anyone please help me out. Thanks
regards,
chinglai

You should have just added that as a comment on your [initial posting|http://forums.sun.com/thread.jspa?threadID=5334953] instead of starting a new thread.
Now, i have a class with the main method. Here, i would like to call the method 'insertStudent' of class 'Student'using the method 'execute' of class 'Teacher', passing the method-name and the class-name (viz. insertStudent, Student) as the
String parameter.
Why oh why? What do you want to achieve?
Let me tell you: there is a way to do what you try to do, but it's not recommended and should be used only very sparingly. Especially not in anything like your code, that resembles normal business logic (as opposed to an application framework such as Spring, for example).
Can you explain what exactly you want to do with that? Why should a Teacher be able to call any random method ony any other class. And what good would that do?

What is the difference between instance variable and class variable?

i've looked it up on a few pages and i'm still struggling a bit maybe one of you guys could "dumb" it down for me or give and example of how their uses differ.
thanks a lot

Instance is variable, class is an object.What? "Instance" doesn't necessarily refer to variables, and although it's true that instances of Class are objects, it's not clear if that's what you meant, or how it's relevant.
if you declare one instance in a class that instance
should be sharing within that class only.Sharing with what? Non-static fields are not shared at all. Sharing which instance? What are you talking about?
if you declare one class object it will share
anywhere in the current program.Err...you can create global variables in Java, more or less, by making them static fields. If that's what you meant. It's not a very good practice though.
Static fields, methods, and classes are not necessarily object types. One can have a static primitive field.

How to create object by getting class name as input

hi
i need to create object for the existing classes by getting class name as input from the user at run time.
how can i do it.
for exapmle ExpnEvaluation is a class, i will get this class name as input and store it in a string
String classname = "ExpnEvaluation";
now how can i create object for the class ExpnEvaluation by using the string classname in which the class name is storted
Thanks in advance

i think we have to cast it, can u help me how to cast
the obj to the classname that i get as inputThat's exactly the point why you shouldn't be doing this. You can't have a dynamic cast at compile time already. It doesn't make sense. Which is also the reason why class.forName().newInstance() is a very nice but also often very useless tool, unless the classes loaded all share a mutual interface.

APT - getting declared variables and parameter names

Hi,
I would like start using APT, but if I am not mistaken, there are severe limitations what you can do with the tool. How is it possible to get the declared name of variables or parameters and methods from the apt tool?
@someAnnotation
public void someMethod(A para1, B para2) {...}I would need to get the name of the method and the name of the parameters to generate new sourcecode (AspectJ -Source), how is this possible? Without the names I cannot call the method from another place right?
Where can I find the planned features for APT? It is a pitty that the tool is in a way very powerful and in another so limitated because you cannot extract the sourcecode or names.
Regards,
Klaas

What about getSimpleName? This method is defined on
declarations.You know, ParameterDeclaration is a Declaration ...
All of the declarations returned by
the mirror API are for elements that exist inside
classes, not inside methods.Huh? Parameters are an integral part of methods and methods are elements that exist inside classes (or types in general). What's your point?
The apt API does not expose any information about the
interiors of methods or constructors.Oh boy. For a ParameterDeclaration getSimpleName() will return the name of the parameter, e.g. suppose you are "scanning" a standard main method:public static void main(String[] args) {...}and you already have the ParameterDeclaration instance representing the sole parameter of the method, then getSimpleName() will return "args".
BTW - this has nothing to do with exposing interiors. Just try it.

Variable and column name

Hi all,
In an interface, I've got a column which has the same name as a variable.
When I execute it in ODI 10g all is fine.
With ODI 11g, it replace the column name by the variable one. If the variable has no value, I've got an SQLException.
I believe it comes from the colon.
In the execution code, I have
INSERT ... VALUES PROJECT.NAME instead of NAME.
I assume that ODI interprets the NAME with the variable name instead of the column name.
Has anyone experienced it ?
Thanks.

Hi,
I just tried to reproduce your issue, I didn't experience the case where ODI takes variable name instead of column name. ODI should be able to differentiate between column name and variable name with '#' Symbol prefixed to it. Any name prefixed with #, ODI thinks thats a variable and, it need to be declared in a package.
In your case, looks like issue is not with the NAME, its with variable having no value. May be that ODI 10g has a default value. However, if a variable has no value, its definitely going to fail the process.
Regards,
K

How to findout Class type and Class name for a Material

Hi all,
How can we findout the Class name and Classtype assigned to a material. ( Varaint Classification for a material)
MM03-> enterial Materil->Classification Tab
Regards,
Rajesh

check the tables AUSP
check the below link
Material Chassifications
regards
srikanth
Message was edited by: Srikanth Kidambi

Casting and Class names

Hi,
I have a subclass class2 of class1, and an object obj1 has a method .get() that returns an object of class1. I want to use a method from class2 with the get() method inside a class2 method. Currently I have it has ((class2)obj.get()).met1().
Is there anyway to do this cast without using explicitly class2? Also can I create a new object inside a class, of same class, without explicitly using the classname?

Hi,
I have a subclass class2 of class1, and an object obj1
has a method .get() that returns an object of class1.
I want to use a method from class2 with the get()
method inside a class2 method. Currently I have it has
((class2)obj.get()).met1().
Is there anyway to do this cast without using
explicitly class2? Also can I create a new object
inside a class, of same class, without explicitly
using the classname?1. Is method.get() in Class1? and Class2 extending Class1?
2. Try this.get().met1();
3. Post your code please!!!

High number of "The connection has timed out" errors. Where do I set the time out period (variable and file name) - windows 7

I usually use a wireless network at home and have very few time out problems with Firefox.
I am travelling and using Optus Wireless broadband where the average ping to a site is 700+ms .
I suspect that this is the cause of the high number of timeouts I am experiencing.
Optus say there are no problems so I think I will have to set the timeout to a longer period.
Please advise what variable name/s (and in which file) the timeout is set for LOADING PAGES.
Thanks in anticipation.
Greg Atkinson.
By the way the same is happening in IE8
and on many sites other than the Yahoo one below.
================Full Error Page ==============
URL is http://au.mg4.mail.yahoo.com/dc/launch?.gx=1&.rand=81jkv757qfdqt
=========================================
The connection has timed out
The server at au.mg4.mail.yahoo.com is taking too long to respond.
* The site could be temporarily unavailable or too busy. Try again in a few moments.
* If you are unable to load any pages, check your computer's network connection.
* If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the Web.

Having the same problem 4 out of 5 times I try to navigate to a new site I get the error "connection has timed out".
My I phone works fine on the same wireless connection so it must be something to do with the computer. The problem occurs on IE, firefox, and google chrome.
I too would like to know how to how to either fix this problem or failing that to extend the length of time before the connection times out (which is currently only about 5 seconds).
Please help!
Thanks in advance

Shared Variable and classes

Hi friends,
1.can you tell me the Disadvantages of Shared Variables?
2.What is classes ,how to make it?
Raj

Hi! Raj
Shared Variables
shared variables share data between loops on a single diagram or between VIs across the network. For doing that they break the LabVIEW dataflow paradigm.
Disadvantages:
1. Using variables allows for race conditions and incurs more overhead than passing the data by wire(break the LabVIEW dataflow paradigm).
Race conditions happen when you, for example, write data to a shared resource from multiple operations faster than you read data from the same shared resource.
2.You must have a project open to create a shared variable
You can also read more about shared variables at http://zone.ni.com/devzone/cda/tut/p/id/4679
Attachments:
Race condition.PNG ‏57 KB

An object variable and class name

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