Final class CL_PT_EMPLOYEE. Why?

Today I tried to make a local class as a sub class to CL_PT_EMPLOYEE and found out that this class was defined as a final class.
Does any one have an idea why the class CL_PT_EMPLOYEE has been defined as a final class. Is that to stop any re-use of SAP code. Any one from SAP?
(P.S. Please dont over exert yourself in explaining the meaning of a final class to me)

Hello Ahsan,
Sorry if I wasn't clear, this is an example of sarcasm. The use of the word "apparently" should have given it away, and particularly the exaggeration "untold harm" was supposed to convey the impression that I do not believe this for one minute.
This is just what I was told by OSS, it was about two years ago and there were several conversations back and forth, some by telephone. Basically, by allowing us to create a subclass we would be able to redefine a superclass method and... well, I am not quite sure what the risk is to be honest, but SAP seemed to think this was a dangerous tool to let loose upon us customers. It was the type of response that is under discussion in this thread:
A (disbelieving) question regarding the OSS
As others have a really suggested, composition is the answer and usually a better technique.
The only time when you should need to create a subtype of a standard SAP class is if you have to use polymorphism to feed your own version of an SAP class to something else that expects a particular class as input. This is the <sarcasm>"risky" part by which we could damage the system according to OSS</sarcasm>, yet is quite commonly used in workflow. In the BOR world they even provided a neat feature called delegation (basically a reverse inheritance) to accomplish this.
Cheers,
Mike
Edited by: Mike Pokraka on Sep 2, 2008 5:59 PM - clarification

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EJP wrote:
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Edited by: jezzica85 on Apr 7, 2009 2:43 PM

jezzica85 wrote:
Thanks DrClap,
You just saved me a lot of time and work. I thought making a class immutable helped with synchronization and keeping values consistent, looks like I misunderstood the Java tutorials, among other things.
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I created boolean references in my main vi block diagram and copied them to my sub vi front panel. when wire my reference in my main vi to one the input node of the sub vi the wire is broken. the error says its a class conflict why?

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Expanding and clarifying what BJD said;
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please help me

You can't inherit from a final class.
So - are you trying to inherit from a final class?
Sincerely,
Ted Ueda

Final method and final class

What is final method and final class in abap objects.

ejp wrote:
Since that doesn't work--or would overyy complex to implement... would be impossible to implement. Once the method-local copy goes out of existence, ipso facto it can never be changed. This is the whole point.I consider it impossible too, but I'm not a language/compiler/runtime expert, so I allowed for the possibility that there could be some way to do it--e.g. local variables that are references in inner classes live on the heap instead of the stack, or something. My point isn't that it's possible, just that if it were somehow to be done, it would by ugly, so we may as well consider it impossible--it just ain't gonna happen.
we go with the logic, "Okay, we need to copies, but keeping them in sync is a nightmareNo, it is +meaningless.+No, it's not meaningless. If we have the two copies, and they're not final, then after the inner object is created, the method can continue running, and either the method or the inner object could modify its copy. As far as our code knows, it's the same variable, so there'd have to be some way to keep them in sync. That's either impossible or undesirably complex--like the above, it doesn't matter which--so it's final in order to get past the issue of keeping the copies in sync.

Abstract class & final class

Which is more correct... Or which is the more preferred way.
abstract class A
final method1(){}
final method2(){}
final method30(){}
}or
final class A
private A(){}
method1(){}
method2(){}
method3(){}
}My understanding is that both classes cannot be instantiated. The first one requires writing 'final' for EACH method. The second one involves writing a private constructor.

It depends on what you are trying to do. If you are trying to make a class that can be sub-classed but has some methods that cannot be overriden, then "abstract class A" with final methods is the way to go. If you want a class that cannot be sub-classed or instantiated then "final class A" with private constructor is the way to go.
classes cannot be instantiatedOnly true for "final class A" because you made the only constructor private. Not true for the abstract one.// you forgot return values for the methods
abstract class A
final static /*void*/ method1(){} // package private
final static /*void*/ method2(){} // package private
final static /*void*/ method30(){} // package private
// this would work
A a = new A(){};
// if I am in the same package as A, then this would work
a.method1();
// or this
public class B extends A
public B(String whatever)
    // Although, I cannot override the super methods
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    // declared them as package private instead of class "private"
}Using final as a class modifier disables the ability to sub-class it but does not disable the ability to create an object of that class. You must make a private constructer. If the only constructor is "private" then you can't subclass or instantiate, so making the class final is uneeded.

How do I redefine a Method of a Final Class?

Hi,
Is it possible to redefine a method of a final class and if so, can someone please give me a brief example of that technique?
Thank you very much!
Andy

Hi,
Please find the example.
Program Description :      Interface I1 contains two methods : M1 and M2.
I1 is included and incorporated in class : C1 with M2 as a final method. Both the methods are implemented in class C1.
Class C2 is a subclass of class C1. It redefines method : I1M1 and re-implements it, but it does not do that for I1M2 as that is declared as final method.
In the START-OF-SELECTION block, object OREF1 is created from class C1 and OREF2 from class C2 and both the methods M1 and M2 are called using both the objects.
Example:
report ytest .
interface i1 .
methods : m1 ,
            m2 .
endinterface.
class c1 definition.
public section.
   interfaces : I1 final methods m2 .
endclass.
class c1 implementation.
method i1~m1.
   write:/5 'I am m1 in c1'.
endmethod.
method i1~m2.
   write:/5 'I am m2 in c1'.
endmethod.
endclass.
class c2 definition inheriting from c1.
public section.
   methods : i1~m1 redefinition .
endclass.
class c2 implementation.
method : i1~m1.
   write:/5 'I am m1 in c2'.
endmethod.
endclass.
start-of-selection.
data : oref1 type ref to c1,
         oref2 type ref to c2 .
   create object : oref1 , oref2.
   call method : oref1->i1~m1 , u201C Output : I am m1 in c1
                  oref2->i1~m1 , u201C Output : I am m1 in c2
                  oref1->i1~m2 , u201C Output : I am m2 in c1
                  oref2->i1~m2 . u201C Output : I am m2 in c1
Output :      I am m1 in c1
I am m1 in c2
I am m2 in c1
I am m2 in c1
Thanks,
Anitha

Clientgen Exception - java.lang.VerifyError:Cannot inherit from final class

When i create a client jar from webservice ear the ant taks fails with compiler errors, such as:
CreateProxy:
[clientgen] Generating client jar for earname.ear(WebServiceName_WS) ...
BUILD FAILED
java.lang.VerifyError: Cannot inherit from final class
at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:539)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:123)
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at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:182)
at java.lang.ClassLoader.loadClass(ClassLoader.java:289)
at java.lang.ClassLoader.loadClass(ClassLoader.java:235)
at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:224)
at weblogic.webservice.server.WebServiceFactory.loadNonArrayClass(WebServiceFactory.java:1318)
at weblogic.webservice.server.WebServiceFactory.loadClass(WebServiceFactory.java:1293)
at weblogic.webservice.server.WebServiceFactory.initTypeMaps(WebServiceFactory.java:384)
at weblogic.webservice.server.WebServiceFactory.createFromMBean(WebServiceFactory.java:184)
at weblogic.webservice.tools.build.internal.WSDLGenImpl.getWebServiceRuntime(WSDLGenImpl.java:240)
at weblogic.webservice.tools.build.internal.WSDLGenImpl.run(WSDLGenImpl.java:135)
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at weblogic.webservice.tools.build.internal.ClientGenImpl.run(ClientGenImpl.java:345)
at weblogic.ant.taskdefs.webservices.clientgen.ClientGenTask.doClientGen(ClientGenTask.java:351)
at weblogic.ant.taskdefs.webservices.clientgen.ClientGenTask.execute(ClientGenTask.java:208)
at org.apache.tools.ant.Task.perform(Task.java:341)
at org.apache.tools.ant.Target.execute(Target.java:309)
at org.apache.tools.ant.Target.performTasks(Target.java:336)
at org.apache.tools.ant.Project.executeTarget(Project.java:1339)
at org.apache.tools.ant.Project.executeTargets(Project.java:1255)
at org.apache.tools.ant.Main.runBuild(Main.java:609)
at org.apache.tools.ant.Main.start(Main.java:196)
at org.apache.tools.ant.Main.main(Main.java:235)
Total time: 25 seconds
This is a ant command:
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My webservice do not include any final class.
I'm using WebLogic 8.1 SP4.Is there a solution for above problem?
Thanks.
Regards.

Hi all,
I m also facing quite similar problem.
I have one sample JMX program, which i want to collect data from weblogic 9.2.
but when i compile sample program on jdk 1.4 and run it on JDK 1.4 it throws following exception
java.lang.VerifyError: class weblogic.utils.classloaders.GenericCl
assLoader overrides final method .
ERROR 02/13 09:54:03 Stderr 700100 at java.lang.ClassLoader.defineClass0(Native Method)
ERROR 02/13 09:54:03 Stderr 700100 at java.lang.ClassLoader.defineClass(Unknown Source)
ERROR 02/13 09:54:03 Stderr 700100 at java.security.SecureClassLoader.defineClass(Unknown Source)
ERROR 02/13 09:54:03 Stderr 700100 at java.net.URLClassLoader.defineClass(Unknown Source)
ERROR 02/13 09:54:03 Stderr 700100 at java.net.URLClassLoader.access$100(Unknown Source)
ERROR 02/13 09:54:03 Stderr 700100 at java.net.URLClassLoader$1.run(Unknown Source)
ERROR 02/13 09:54:03 Stderr 700100 at java.security.AccessController.doPrivileged(Native Method)
ERROR 02/13 09:54:03 Stderr 700100 at java.net.URLClassLoader.findClass(Unknown Source)
ERROR 02/13 09:54:03 Stderr 700100 at java.lang.ClassLoader.loadClass(Unknown Source)
ERROR 02/13 09:54:03 Stderr 700100 at java.lang.ClassLoader.loadClass(Unknown Source)
but sample program works fine if i run it on JDK 1.5..
can someone tell me...wats reason?
Thanks
Nihil

Protected method in Final Class

Hi all
Can we have protected method in Final class ?
If so how is it possible ?
Vicky

Final classes cannot have subclasses and hence no need of protected methods.
No comments on possibility.
Check this link from SAP help to know more :
http://help.sap.com/saphelp_nw70/helpdata/en/dd/4049c40f4611d3b9380000e8353423/content.htm
Hope this helps you.
Edited by: Harsh Bhalla on Dec 19, 2009 3:35 PM

Final class CL_PT_EMPLOYEE. Why?

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