Inner classes

can any some detailed information,faq's regarding inner classes,typecasting of variables and objects in abap and oops,not other than that.I will be very thankful to those who have done it.

Hi,
check out the ABAP development guide. It contains a lo helpful information regarding ABAP OO.
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/c1be1003-0701-0010-3795-f87160de6483
cheers
Thomas

Similar Messages

Problem with Outer and Inner Classes....or better way?

Right now I'm trying to create an Inner class.
My .java file compiles ok, and I create my jar file too.
But when I try to instantiate the Inner class, it fails:
java.lang.NoClassDefFoundError: com/myco/vlXML/vlXML$vlDocument.
Here's the class code:
public class vlXML{
    private ArrayList myDocList=new ArrayList(); //holds documents
    public vlXML(){
    private class vlDocument{
        public vlDocument(){
        //stuff goes here
    public vlDocument vlDOC(){
        return new vlDocument();
    public void addDocument(){
        vlXML xxx=new vlXML();
        vlDocument myDoc=xxx.vlDOC();
        myDocList.add(myDoc);
    public int getNumDocs(){
        return myDocList.size();
}Then, from a jsp page, I call:
vlXML junk1=new vlXML();
junk1.addDocument();...and get the error...
Can someone help me figure out why it's failing?
Thanks....

You nailed it - thanks....(duh!)
While I have your attention, if you don't mind, I have another question.
I'm creating a Class (outer) that allows my users to write a specific XML file (according to my own schema).
Within the XML file, they can have multiple instances of certain tags, like "Document". "Document"s can have multiple fields.
Since I don't know how many "Documents" they may want, I was planning on using an Inner Class of "Document", and then simply letting them "add" as many as necessary (thus the original code posted here).
Does that seem like an efficient (logical/reasonable) methodology,
or is there there something better?
Thanks Again...

Problem with final variables and inner classes

variables accessed by inner classes need to be final. Else it gives compilation error. Such clases work finw from prompt. But when I try to run such classes through webstart it gives me error/exception for those final variables being accessed from inner class.
Is there any solution to this?
Exception is:
java.lang.ClassFormatError: com/icorbroker/fx/client/screens/batchorder/BatchOrderFrame$2 (Illegal Variable name " val$l_table")
 at java.lang.ClassLoader.defineClass0(Native Method)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:502)
 at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:123)
 at com.sun.jnlp.JNLPClassLoader.defineClass(Unknown Source)
 at com.sun.jnlp.JNLPClassLoader.access$1(Unknown Source)
 at com.sun.jnlp.JNLPClassLoader$1.run(Unknown Source)
 at java.security.AccessController.doPrivileged(Native Method)
 at com.sun.jnlp.JNLPClassLoader.findClass(Unknown Source)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:299)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:255)
 at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:315)
 at com.icorbroker.fx.client.screens.batchorder.BatchOrderFrame.<init>(BatchOrderFrame.java:217)
 at com.icorbroker.fx.client.screens.batchorder.BatchOrderViewController.createView(BatchOrderViewController.java:150)
 at com.icorbroker.fx.client.screens.RealTimeViewController.initialize(RealTimeViewController.java:23)
 at com.icorbroker.fx.client.screens.batchorder.BatchOrderViewController.<init>(BatchOrderViewController.java:62)
 at com.icorbroker.fx.client.screens.displayelements.DisplayPanel$3.mousePressed(DisplayPanel.java:267)
 at java.awt.Component.processMouseEvent(Component.java:5131)
 at java.awt.Component.processEvent(Component.java:4931)
 at java.awt.Container.processEvent(Container.java:1566)
 at java.awt.Component.dispatchEventImpl(Component.java:3639)
 at java.awt.Container.dispatchEventImpl(Container.java:1623)
 at java.awt.Component.dispatchEvent(Component.java:3480)
 at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3450)
 at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3162)
 at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3095)
 at java.awt.Container.dispatchEventImpl(Container.java:1609)
 at java.awt.Window.dispatchEventImpl(Window.java:1590)
 at java.awt.Component.dispatchEvent(Component.java:3480)
 at java.awt.EventQueue.dispatchEvent(EventQueue.java:450)
 at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:197)
 at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
 at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:144)
 at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:136)
 at java.awt.EventDispatchThread.run(EventDispatchThread.java:99)

I've also been having the same problem. The only work-around seems to be to slightly change the code, recompile & hope it works. See http://forum.java.sun.com/thread.jsp?forum=38&thread=372291

Problem with final variables and inner classes (JDK1.1.8)

When using JDK1.1.8, I came up with following:
public class Outer
    protected final int i;
    protected Inner inner = null;
    public Outer(int value)
        i = value;
        inner = new Inner();
        inner.foo();
    protected class Inner
        public void foo()
            System.out.println(i);
}causing this:
Outer.java:6: Blank final variable 'i' may not have been initialized. It must be assigned a value in an initializer, or in every constructor.
public Outer(int value)
^
1 error
With JDK 1.3 this works just fine, as it does with 1.1.8 if
1) I don't use inner class, or
2) I assign the value in initializer, or
3) I leave the keyword final away.
and none of these is actually an option for me, neither using a newer JDK, if only there is another way to solve this.
Reasons why I am trying to do this:
1) I can't use a newer JDK
2) I want to be able to assign the variables value in constructor
3) I want to prevent anyone (including myself ;)) from changing the value in other parts of the class (yes, the code above is just to give you the idea, not the whole code)
4) I must be able to use inner classes
So, does anyone have a suggestion how to solve this problem of mine? Or can someone say that this is a JDK 1.1.8 feature, and that I just have to live with it? In that case, sticking to solution 3 is probably the best alternative here, at least for me (and hope that no-one will change the variables value). Or is it crappy planning..?

You cannot use a final field if you do not
initialize it at the time of declaration. So yes,
your design is invalid.Sorry if I am being a bit too stubborn or something. :) I am just honestly a bit puzzled, since... If I cannot use a final field in an aforementioned situation, why does following work? (JDK 1.3.1 on Linux)
public class Outer {
        protected final String str;
        public Outer(String paramStr) {
                str = paramStr;
                Inner in = new Inner();
                in.foo();
        public void foo() {
                System.out.println("Outer.foo(): " + str);
        public static void main( String args[] ) {
                String param = new String("This is test.");
                Outer outer = new Outer(param);
                outer.foo();
        protected class Inner {
                public void foo() {
                        System.out.println("Inner.foo(): " + str);
} producing the following:
[1:39] % javac Outer.java
[1:39] % java Outer
Inner.foo(): This is test.
Outer.foo(): This is test.
Is this then an "undocumented feature", working even though it shouldn't work?
However, I assume you could
get by with eliminating the final field and simply
passing the value directly to the Inner class's
constructor. if not, you'll have to rethink larger
aspects of your design.I guess this is the way it must be done.
Jussi

Problem with constructor of inner class.

Hi everybody!
I have an applet which loads images from a database.
i want to draw the images in a textarea, so i wrote an inner class, which extends textarea and overrides the paint method.
but everytime i try to disply the applet in the browser this happens:
java.lang.NoClassDefFoundError: WohnungSuchenApplet$Malfl�che
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:1590)
at java.lang.Class.getConstructor0(Class.java:1762)
at java.lang.Class.newInstance0(Class.java:276)
at java.lang.Class.newInstance(Class.java:259)
at sun.applet.AppletPanel.createApplet(AppletPanel.java:567)
at sun.plugin.AppletViewer.createApplet(AppletViewer.java:1778)
at sun.applet.AppletPanel.runLoader(AppletPanel.java:496)
at sun.applet.AppletPanel.run(AppletPanel.java:293)
at java.lang.Thread.run(Thread.java:536)
so my class has no own constructor, it just has the paint method overwritten.
my class looks like this:
public class Malfl�che extends javax.swing.JTextArea{
public void paint(Graphics g){
Color grey=new Color(220,220,220);
g.drawImage(img,10,10,null);
how should a constructor for this class look like?
sorry i am quite new to this, so i really dont have a clue!
my class does not have any attributes or requires any so it doesnt need a constructor, doesnt it?
thanks a lot
tim

First off, unlike regular classes, inner classes can be declared public, private, protected, and default.
Secondly, why are you using the JTextArea to display an image, why not use a JLabel, which takes an Image object as its constructor.
Thirdly, when you drew your image you did not give it a width and height
g.drawImage(img, 0,0, img.getWidth(null), img.getHeight(null), null);
otherwise it will make your image 1 X 1 pixels. not big enough to see.

Help: Factory Class using Inner Class and Private Constructor?

The situation is as follows:
I want a GamesCollection class that instantiates Game objects by looking up the information needed from a database. I would like to use Game outside of GamesCollection, but only have it instantiated by GamesCollection to ensure the game actually exist. Each Game object is linked to a database record. If a Game object exist, it must also exist in the database. Game objects can never be removed from the database.
I thought about making the Game object an inner class of GamesCollection, but this means that Game class constructor is still visible outside. So what if I made Game constructor private? Well, now I can't create Game objects without a static method inside Game class (static Object factory).
Basically what I need is a constructor for the inner Game class accessible to GamesCollection, but not to the rest of the world (including packages). Is there a way to do this?

leesiulung wrote:
As a second look, I was initially confused about your first implementation, but it now makes more sense.
Let me make sure I understand this:
- the interface is needed to make the class accessible outside the outer classBetter: it is necessary to have a type that is accessible outside of GameCollection -- what else could be the return type of instance?
- the instance() method is the object factory
- the private modifier for the inner class is to prevent outside classes to instantiate this objectRight.
However, is a private inner class accessible in the outer class? Try it and see.
How does this affect private/public modifiers on inner classes?Take about five minutes and write a few tests. That should answer any questions you may have.
How do instantiate a GameImpl object? This basically goes back to the first question.Filling out the initial solution:
public interface Game {
    String method();
public class GameCollection {
    private static class GameImpl implements Game {
        public String method() {
            return "GameImpl";
    public Game instance() {
        return new GameImpl();
    public static void main(String[] args) {
        GameCollection app = new GameCollection();
        Game game = app.instance();
        System.out.println(game.method());
}Even if you were not interested in controlling game creation, defining interfaces for key concepts like Game is always going to be a good idea. Consider how you will write testing code, for example. How will you mock Game?

Threaded inner classes & heap memory exhaustion

(_) how can i maximize my threading without running out of
heap memory?
push it to the limit, but throttle back before an
java.lang.OutOfMemoryError.
(_) within 1 threaded class ThreadClass, i have two threaded inner classes. for each instance of ThreadClass i only
start one instance of each inner class.
and, i start hundreds of ThreadClass, but not until the previously running ThreadClass object exits, so only one should be running at any given time.
so, what about threaded inner classes?
are they good? bad? cause "OutOfMemoryErrors"?
are those inner threads not dying?
what are common causes of:
java.lang.OutOfMemoryError: java heap space?
my program runs for about 5-minutes, then
bails with the memory error.
how can i drill down and see what
is eating-up all my memory?
thanks.

A Thread class is not the same as a thread of
execution. Those inner class based threads of
execution are not dying.maybe. but this is the way i test a thread's life:
public void run() {
System.out.println("thread start");
System.out.println("thread dies and release memory");
}for each inner thread, and the outer thread, this approach for
testing thread life reveals that they die.
Why don't you use a thread pool?ok. i will think about how to do this.
>
If not, you need to ensure those inner threads have
exited and completed.what is a 100% sure check to guarantee a thread exits other than
the one i use above?
note:
the outer thread is running on a remote host, and the inner threads
are running locally. here are the details:
public class BB implements Runnable, FinInterface {
public void run() {
    // do some work on the remote machine
private void startResultsHandler(OisXoos oisX) {
     ResultHandler rh = new ResultHandler(oisX);
     rh.start();
public void startDataProxy(OisXoos oisX, String query) {
     DataProxy dp = new DataProxy(oisX, query);
     dp.start();
        public class ResultsHandler extends Thread {
           // runs locally; waits for results from servers
           public void run() {
               ObjectInputStream ois = new ObjectInputStream(oisX.input);
                Set result = (Set) ois.readObject();
        } // ____ class :: _ ResultsHandler _ :: class ____
       public class DataProxy extends Thread {
           // runs locally; performs db queries on behalf of servers
           public void run() {
               ObjectOutputStream oos = new ObjectOutputStream(oisX.output);
                while(moreData) {
                    .... // sql queries
                    oos.writeObject(data);
             StartResultsHandler(oisX);
        } // _____ class :: _ DataProxy _ :: class _____
}now, the BB class is not started locally.
the inner threads are started locally to both service data requests
by the BB thread as well as wait for its results.
(_) so, maybe the inner threads cannot exit (but they sure look
like they exit) until their parent BB thread exits.
(_) yet, those inner threads have no knowledge that the BB
thread is running.
externalizing those inner thread classes will put 2-weeks of work
in the dust bin. i want to keep them internal.
thanks.
here this piece of code that controls everything:
while(moreData) {
FinObjects finObj = new BB();
String symb = (String) data_ois.readObject();
OisXoos oisX = RSAdmin.getServer();
oisX.xoos.writeObject(finObj);
finObj.startDataProxy(finObj, oisX, symb);
}

Compiler error when useing switch statements in an inner class

I have defined several constants in a class and want to use this constans also in an inner class.
All the constants are defined as private static final int.
All works fine except when useing the switch statement in the inner class. I get the compiler error ""constant expression required". If I change the definition from private static final to protected static final it works, but why?
What's the difference?
Look at an example:
public class Switchtest
 private static final int AA = 0;
 protected static final int BB = 1;
 private static int i = 0;
 public Switchtest()
 i = 0; // <- OK
 switch(i)
 case AA: break; //<- OK, funny no problem
 case BB: break; //<- OK
 default: break;
private class InnerClass
 public InnerClass()
 i = 0; // <- OK: is accessible
 if (AA == i) // <- OK: AA is seen by the inner class; i is also accessible
 i = AA + 1;
 switch(i)
 case AA: break; // <- STRANGE?! Fail: Constant expression required
 case BB: break; // <- OK
 default: break;
}Thank's a lot for an explanation.

Just a though:
Maybe some subclass of Switchtest could decalare its own variable AA that is not final, but it can not declare its own BB because it is visible from the superclass. Therefore the compiler can not know for sure that AA is final.

Passing Inner class name as parameter

Hi,
How i can pass inner class name as parameter which is used to create object of inner class in the receiving method (class.formane(className))
Hope somebody can help me.
Thanks in advance.
Prem

No, because an inner class can never have a constructor that doesn't take any arguments.
Without going through reflection, you always need an instance of the outer class to instantiate the inner class. Internally this instance is passed as a parameter to the inner class's constructor. So to create an instance of an inner class through reflection you need to get the appropriate constructor and call its newInstance method. Here's a complete example:import java.lang.reflect.Constructor;
class Outer {
    class Inner {
    public static void main(String[] args) throws Exception{
        Class c = Class.forName("Outer$Inner");
        Constructor cnstrctr = c.getDeclaredConstructor(new Class[] {Outer.class});
        Outer o = new Outer();
        Inner i = (Inner) cnstrctr.newInstance(new Object[]{o});
        System.out.println(i);
}

How to call inner class method in one java file from another java file?

hello guyz, i m tryin to access an inner class method defined in one class from another class... i m posting the code too wit error. plz help me out.
// test1.java
public class test1
     public test1()
          test t = new test();
     public class test
          test()
          public int geti()
               int i=10;
               return i;
// test2.java
class test2
     public static void main(String[] args)
          test1 t1 = new test1();
          System.out.println(t1.t.i);
i m getting error as
test2.java:7: cannot resolve symbol
symbol : variable t
location: class test1
          System.out.println(t1.t.geti());
^

There are various ways to define and use nested classes. Here is a common pattern. The inner class is private but implements an interface visible to the client. The enclosing class provides a factory method to create instances of the inner class.
interface I {
    void method();
class Outer {
    private String name;
    public Outer(String name) {
        this.name = name;
    public I createInner() {
        return new Inner();
    private class Inner implements I {
        public void method() {
            System.out.format("Enclosing object's name is %s%n", name);
public class Demo {
    public static void main(String[] args) {
        Outer outer = new Outer("Otto");
        I junior = outer.createInner();
        junior.method();
}

How to access var in outter class inside inner class

I've problem with this, how to access var number1 and number2 at outter class inside inner class? what statement do i have to use to access it ? i tried with " int number1 = Kalkulator1.this.number1; " but there no value at class option var y when the program was running...
import java.io.*;
public class Kalkulator1{
int number1,number2,x;
/* The short way to create instance object for input console*/
private static BufferedReader stdin =
new BufferedReader( new InputStreamReader( System.in ) );
public static void main(String[] args)throws IOException {
System.out.println("---------------------------------------");
System.out.println("Kalkulator Sayur by Cumi ");
System.out.println("---------------------------------------");
System.out.println("Tentukan jenis operasi bilangan [0-4] ");
System.out.println(" 1. Penjumlahan ");
System.out.println(" 2. Pengurangan ");
System.out.println(" 3. Perkalian ");
System.out.println(" 4. Pembagian ");
System.out.println("---------------------------------------");
System.out.print(" Masukan jenis operasi : ");
String ops = stdin.readLine();
     int numberops = Integer.parseInt( ops );
System.out.print("Masukan Bilangan ke-1 : ");
String input1 = stdin.readLine();
int number1 = Integer.parseInt( input1 );
System.out.print("Masukan Bilangan ke-2 : ");
String input2 = stdin.readLine();
int number2 = Integer.parseInt( input2 );
     Kalkulator1 op = new Kalkulator1();
Kalkulator1.option b = op.new option();
     b.pilihan(numberops);
System.out.println("Bilangan yang dimasukkan adalah = " + number1 +" dan "+ number2 );
class option{
int x,y;
     int number1 = Kalkulator1.this.number1;
     int number2 = Kalkulator1.this.number2;
void pilihan(int x) {
if (x == 1)
{System.out.println("Operasi yang digunakan adalah Penjumlahan");
        int y = (number1+number2);
        System.out.println("Hasil dari operasi adalah = " + y);}
else
{if (x == 2) {System.out.println("Operasi yang digunakan adalah Pengurangan");
         int y = (number1-number2);
         System.out.println("Hasil dari operasi adalah = " + y);}
else
{if (x == 3) {System.out.println("Operasi yang digunakan adalah Perkalian");
         int y = (number1*number2);
         System.out.println("Hasil dari operasi adalah = " + y);}
else
{if (x == 4) {System.out.println("Operasi yang digunakan adalah Pembagian ");
         int y = (number1/number2);
         System.out.println("Hasil dari operasi adalah =" + y);}
else {System.out.println( "Operasi yang digunakan adalah Pembagian ");
}

Delete the variables number1 and number2 from your inner class. Your inner class can access the variables in the outer class directly. Unless you need the inner and outer class variables to hold different values then you can give them different names.
In future place code tags around your code to make it retain formatting. Highlight code and click code button.

How to pass a variable value to an inner class?

Hi there,
Please have a look of the code below. It's a bit long, but my concern is I did have to declare the int "i" variable as static because it is used by an inner class (if "i" is not declare as static, the code cannot be compiled).
Is there a more "clean" way to do the way work without declaring the "i" int as static? (because the scope of this variable is not the whole program).
Thanks for your help.
Denis
import java.util.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class Tools{
 static int i;
 static void longTask(){
 for (Tools.i=0; Tools.i<=100; Tools.i++) {
 SwingUtilities.invokeLater( new Runnable(){
 public void run(){
 myApp.jpb.setValue(Tools.i);//--- static variable i
 for (int j=0; j<200; j++)
 System.out.println(Tools.i+" - "+j);
class myListener implements ActionListener{
 public void actionPerformed(ActionEvent e){
 Thread t = new Thread() {
 public void run(){
 Tools.longTask();
 t.start();
public class myApp {
 static JProgressBar jpb;
 public static void main(String[] args) {
 JFrame frame = new JFrame();
 JPanel panel = new JPanel(new FlowLayout());
 jpb = new JProgressBar();
 jpb.setValue(0);
 jpb.setStringPainted(true);
 JButton button = new JButton("go");
 button.addActionListener(new myListener());
 panel.add(jpb);
 panel.add(button);
 frame.getContentPane().add( panel, BorderLayout.CENTER);
 frame.setVisible(true);
 frame.pack();
}

Without compiling it, writing it in notepad, it would be something like this. You should also wonder if this longTask has to be static by the way. But I think this demonstrates the inner class stuff. You can also look in the tutorial on this site: http://java.sun.com/docs/books/tutorial/essential/threads/timer.html
class Tools{
 static int i;
 static void longTask(){
 for (Tools.i=0; Tools.i<=100; Tools.i++) {
 SwingUtilities.invokeLater( new Innerclass(i));
 for (int j=0; j<200; j++) {
 System.out.println(Tools.i+" - "+j);
 Class Innerclass implements Runnable(){
 int i;
 public Innerclass(int i) {
 this.i = i;
 public void run(){
 myApp.jpb.setValue(Tools.i);//--- static variable i
}

Static inner class causes deployment on OC4J 10.1.2 to fail

Hi,
this issue has already been raised on OC4J 9.0.4 with J2SDK 1.4.2 (see EJB fails to compile - static inner class problem
Recap: When referencing static inner classes in an EJB, the deployment fails. During the generation of the wrapper classes, a signature <package>.<outer class>.<inner class> gets converted to <package>.<outer class>$<inner class>, which is syntactically wrong. While the Java 1.4.1 compiler kindly ignores this syntax error, its 1.4.2 counterpart complains - and fails.
@Oracle: When will this bug be fixed for OC4J 10.1.2?
Best regards,
Holger

Holger,
Don't static inner classes contradict the EJB specification?
In any case, in answer to Andy's question: If you wish to file this as a bug, you can do so via the MetaLink Web site.
[In fact, [i]MetaLink is your only option for submitting bugs for Oracle products -- as far as I know.]
Good Luck,
Avi.

Inner classes in ABAP

Hello!
Is it possible to declare inner classes, that is, classes within classes in ABAP? If yes, please provide example.
Thanks!
Kind regards,
Igor

> No. I need a class to be declared within a class, or
> even within a method in order to make it visible only
> to the containing class (or method).
You cannot nest class declarations, but there happens to be a way of implementing the functionality you desire, though too tedious to be useful practically. You can use a combination of a "CREATE PRIVATE" class and the Friendship idea to do this. A quick and dirty example is :
REPORT zootest.
CLASS lcl_test_outer DEFINITION DEFERRED.
* CLASS lcl_test_inner DEFINITION
CLASS lcl_test_inner
 DEFINITION CREATE PRIVATE
 FRIENDS lcl_test_outer.
PUBLIC SECTION.
 DATA: test.
ENDCLASS.
* CLASS lcl_test_outer DEFINITION
CLASS lcl_test_outer DEFINITION.
PUBLIC SECTION.
 METHODS: test_inst.
ENDCLASS.
* CLASS lcl_test_outer IMPLEMENTATION
CLASS lcl_test_outer IMPLEMENTATION.
METHOD test_inst.
 DATA: ref1 TYPE REF TO lcl_test_inner.
 CREATE OBJECT ref1.
ENDMETHOD.
ENDCLASS.
DATA: ref1 TYPE REF TO lcl_test_inner,
 ref2 TYPE REF TO lcl_test_outer.
START-OF-SELECTION.
CREATE OBJECT ref2.
Crude, but it can be refined further, but I hope this helps
Regards,
Dushyant Shetty

Trying to use super class's methods from an anonymous inner class

Hi all,
I have one class with some methods, and a second class which inherits from the first. The second class contains a method which starts up a thread, which is an anonymous inner class. Inside this inner class, I want to call a method from my first class. How can I do this?
If I just call the method, it will use the second class's version of the method. However, if I use "super," it will try to find that method in the Thread class (it's own super class) and complain.
Any suggestions?
Code:
public class TopClass
     public void doSomething(){
          // do something
=============================
public class LowerClass extends TopClass
     // overrides TopClass's doSomething.
     public void doSomething(){
          // do something
     public void testThread(){
          Thread t = new Thread(){
               public void run(){
                    doSomething();               //fine
                    super.doSomething();          //WRONG: searches class Thread for doSomething...
          t.start();
}

Classes frequently call the un-overridden versions of methods from their superclasses. That's that the super keyword is for, if I'm not mistaken.You're not mistaken about the keyword, but you're not calling the superclass method from a subclass. Your anonymous inner class is not a subtype of TopLevel. It's a subtype of Thread.
Here it is no different, except that I happen to be in a thread at the time.It's vastly different, since you're attempting to call the method from an unrelated class; i.e., Thread.
I could also be in a button's action listener, for example. It seems natural to me that if I can do it in a method, I should be able to do it within an anonymous inner class which is inside a method.If you were in an button's action listener and needed to call a superclass' implementation of a method overridden in the button, I'd have the same questions about your design. It seems smelly to me.
~

Inner classes

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