Access from inner class

hi all,
I have one frame with two panels inside, code likes the following:
public class ShowChart extends JFrame{
Container f = getContentPane();
f.setLayout(new BorderLayout());
JPanel chart=new drawChart();
JPanel setting=new settingChart(chart);
f.add(setting,java.awt.BorderLayout.WEST);
f.add(chart);
class drawChart extends JPanel(){
setTableWidth(int w){...}
class settingChart extends JPanel(){
drawChart chart;
pubic settingChart(drawChart c){
chart=c;
JTextField width = new JTextField("9",4);
add(width);
JButton change = new JButton("Change");
change.addActionListener(new changeHandle(chart));
add(change);
change.addActionListener(new ActionListener()
public void actionPerformed(ActionEvent event){
int w = (int)Double.parseDouble(width.getText());
chart.setTableWidth(w);
Compilling error: local virable chart is accessed from within inner class, need to be declared as final. chart.setTabelWidth(w);
how can i deal with this problem? (i know it will be ok if i messy all the viriables and method of settingChart into the ShowChart class, but it seems not a nice way...)
thanks
dejie

Below is an example of an inner class field 'masking' the name of the outerclass field. So to access the outerclass you use OuterClass.this and then the field of that class...
public class OuterClass {
private int value = 1;
class InnerClass {
    int value = 2;
    public InnerClass() {
      doStuff();
    void doStuff() {
      this.value++;
      OuterClass.this.value++;
}Hope that helps...

Similar Messages

Local variable can't be accessed from inner class ???????? Why ??????

Plesae help, help, help. I have no idea what to do with this bug.........
<code>
for ( int i = 0; i <= 2; i++ ) {
for ( int j = 0; j <= 2; j++ ) {
grids[i][j] = new MyButton ();
grids[i][j].setBorder(but);
getContentPane().add(grids[i][j]);
MyButton sub = grids[i][j];
sub.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if ( sub.getState() == 0 ) {
     sub = new MyButton( (Icon) new ImageIcon(imageFile));
     if ( imageFile.equals("cross.jpg") ) {
          sub.changeState(1);
     else {
          sub.changeState(2);
</code>
The compiler complains that "sub" is in the inner class, which is the ActionListener class, must be declared final. Please tell me what to do with it. I want to add an ActionListener to each MyButton Object in the array. Thanks ......

OK, now I changed my code to this :
for ( int i = 0; i <= 2; i++ ) {
for ( int j = 0; j <= 2; j++ ) {
    grids[i][j] = new MyButton ();
    grids[i][j].setBorder(but);
    getContentPane().add(grids[i][j]);
    grids[i][j].addActionListener(new ActionListener() {
     public void actionPerformed(ActionEvent e) {
        if ( grids[i][j].getState() == 0 ) {
           grids[i][j] = new MyButton( (Icon) new ImageIcon(imageFile));
          if ( imageFile.equals("cross.jpg") ) {
           grids[i][j].changeState(1);
          else {
          grids[i][j].changeState(2);
[/cpde]
Thanks for your advice !!!!!!
Now the compiler says that i and j are local variables accessed from inner classes, needs to be declared final. How can I solve this then ???

How to access super of enclosing class from inner class?

Hello,
I'd like to access Base.foo() from inner class in overridden Improved.foo(), but seem unable:
public class InnerSuper {
     public static class Base {
          protected int foo() {
               return 1;
     public static class Improved extends Base {
          @Override
          protected int foo() {
               return Integer.parseInt(new Object () {
                    public String toString() {
                         return "1"+foo() ;
               }.toString());
     public static void main(String[] args) {
          System.out.println(new Improved().foo());
}The code above does not work, as it recursively calls Improved.foo() where I'd like it to call Base.foo(). What syntax construct should I use? Improved.this would be the same thing, Improved.super does not exist.
I came up with a work around: adding a method baseFoo() to Improved and call that in the inner class:
   int baseFoo() {
      return super.foo();
   } but remain wondering if that is necessary?

Indeed, Improved.super.foo() is allowed. My Eclipse syntax highlighting seems to have the same opinion as you: "are you sure you want to write that kind of code?" and leaves the read underlining for a syntax error on for just a second longer.
This is where I am now:
     public static class DeferredExecSubroutineCall extends SubroutineCall {
          RelayExecutor relay;
          public DeferredExecSubroutineCall(RelayExecutor relay) {
               this.relay = relay;
          @Override
          protected String execute(final IFDSOC fd, final String commandText) {
               Future<String> f = relay.submit(new Callable<String>() {
                    @Override
                    public String call() throws Exception {
                         return DeferredExecSubroutineCall.super.execute(fd, commandText);
               try {
                    return f.get();
               } catch (InterruptedException e) {
                    throw new RuntimeException(e);
               } catch (ExecutionException e) {
                    if (e.getCause() instanceof RuntimeException) {
                         throw (RuntimeException) e.getCause();
                    } else {
                         throw new RuntimeException(e.getCause());
     }which is my current effort of adding concurrency to an existing project. I find it quite elegant but I am interested to hear from you...

Accessing the inner class written inside the method

Hi all,
Can any of you tell me how to access the inner class's method which is written inisde the outer class's method. THe code fragment is
class Outer
private static final int ID = 3;
public String name;
public void methodA( int nn )
final int serialN = 11;
class inner
void showResult()
System.out.println( "Rslt= "+ID );
} // end class inner
// new inner().showResult();
} // end methodA
class Sample
public static void main(String a[])
//access the showResult of Inner class??
Thanks in advance.
aah

class Outer {
private static final int ID = 3;
public String name;
public void methodA( int nn ) {
    final int serialN = 11;
    class inner {
      void showResult() {
        System.out.println( "Rslt= "+ID );
    } // end class inner
    new inner().showResult();
} // end methodA
class Sample {
public static void main(String a[]) {
    new Outer().methodA(5);
}

Inheriting from inner classes

TIJ has a section on inheriting from inner classes, but the author didn't illustrate a scenario. What could be the possible usage? Why would one want to only inherit the inner case, but have to initialize the outter class (which it doesn't want to inherit)?
Example code in the book:
    //: c08:InheritInner.java
    // Inheriting an inner class.
    class WithInner {
      class Inner {}
    public class InheritInner extends WithInner.Inner {
      //! InheritInner() {} // Won't compile
      InheritInner(WithInner wi) {
        wi.super();
      public static void main(String[] args) {
        WithInner wi = new WithInner();
        InheritInner ii = new InheritInner(wi);
    } ///:~

I've certainly never felt the need to extend inner
classes. As far as I'm concerned, inner classes are
great for certain uses, all of which involve them
being private. I've yet to find a scenario where a
non-private inner class is preferable to a 'proper'
class.To make the outer class act as a factory. The inner class is public but the constructors are private.

Accessing Enclosing Class Members From Inner Class Subclass

I have the following scenario that I cannot get to work. Notice the comments in B.doWork() for the problem code. In B.doWork(), how do I access m_strA?
* A.java
* Created on July 5, 2002, 2:20 PM
package Projects.InnerTrouble.Files;
public class A {
     public abstract class InnerA {
          public abstract void doWork ();
     public String m_strA;
     /** Creates new A */
     public A ()
               new InnerA() {
                         public void doWork ()
                                   System.out.println("A$InnerA$1's doWork() called!");
                                   m_strA = "Annonymous subclass of InnerA's doWork did this";
                    }.doWork();
     * @param args the command line arguments
     public static void main (String args[])
               A oTemp = new A();
               System.out.println(oTemp.m_strA);
               B.getB(oTemp).doWork();
               System.out.println(oTemp.m_strA);
class B extends A.InnerA {
     public B (A a)
               a.super();
     public void doWork ()
               System.out.println("B's doWork() called!");
               // How do I access m_strA within B's doWork() method? The following is what I would expect to be the answer, but it does not compile
               // A.this.m_strA = "B's doWork did this";
     private static A.InnerA sm_oInnerA;
     public static A.InnerA getB (A a)
               if (sm_oInnerA == null)
                    sm_oInnerA = new B(a);
               return (sm_oInnerA);

The whole point is that B is not an inner class of A
so it does not have access to A's member variables.
Eventhough B extends an inner class of A, that does
not make B an inner class of A. That is in the JLS,
but not so elegantly as I have put it, hehe.
If B were an innerclass of InnerA, then it would
qualify to access A's member variables.OK, I think that you are finally getting through to my thick skull on this one. Let me restate and get your check-off on my understanding of the situation.
The only classes with access to A's this reference are A and inner classes of A that are found within the definition of A. So, despite the fact that A and B are in the same package (and B should have access to A's non-private members because B and A are in the same package), and despite the fact that we would normally state that B "is a" InnerA (which is an inner class of A and would have access to a reference to the A.this reference), B is not allowed access to A.this (because B "is not really a" InnerA in the same way that the anonymous implementation of InnerA "is a" InnerA). However, nothing would prevent me from giving B access to a reference of the enclosing A as long as it was done via a method of InnerA, and as long as the implementation of that method is contained in A's implementation.
Does this "access" rule realy make sense? Are you aware of the justification for this rule? Or is the justification stated in the JLS? I would think that the compiler ought to be able to figure this kind of thing out and allow it. It seems to me the fact that I defined B in the way that I did, and the fact that B "is a" InnerA, implies that I desired a fairly tight relationship to A. In fact, I desired the exact relationship that exists for the anonymous implementation of InnerA.
The following is a modified version of my original example that runs as I originally wanted it to, but works around the access rules discussed on this forum thread:
* A.java
* Created on July 5, 2002, 2:20 PM
package Projects.InnerTrouble.Files;
public class A {
     public abstract class InnerA {
          public abstract void doWork ();
          /** added to allow implementors of InnerA that are not enclosed in A's class definition to have access to the enclosing class */
          public A myEnclosingInstance ()
                    return (A.this);
     public String m_strA;
     /** Creates new A */
     public A ()
               new InnerA() {
                         public void doWork ()
                                   System.out.println("A$InnerA$1's doWork() called!");
                                   m_strA = "Annonymous subclass of InnerA's doWork did this";
                    }.doWork();
     * @param args the command line arguments
     public static void main (String args[])
               A oTemp = new A();
               System.out.println(oTemp.m_strA);
               B.getB(oTemp).doWork();
               System.out.println(oTemp.m_strA);
class B extends A.InnerA {
     public B (A a)
               a.super();
     public void doWork ()
               System.out.println("B's doWork() called!");
               // The following is what I would expect to be the answer, but it does not compile
               // A.this.m_strA = "B's doWork did this";
               // added myEnclosingInstance() to get functionality desired above
               myEnclosingInstance().m_strA = "B's doWork did this";
     private static A.InnerA sm_oInnerA;
     public static A.InnerA getB (A a)
               if (sm_oInnerA == null)
                    sm_oInnerA = new B(a);
               return (sm_oInnerA);
}

Why eclipse gives me warning if I access in inner class a parent field ?

I have a class
class A{
private Map fValues;
A(){
fValues= new HashMap();
prrotected class B {
B(){
fValues.get("String");
Above class is only for an example to expalin my problem.
Inner class B wants to access fValues from class A .
The eclipse gives me a warning
Access to enclosing method fValues from the type A is emulated by a synthetic accessor method. Increasing its visibility will improve your performance
I order to get rid of this warning I must make fValues public is this the only solution ?
miro

miro_connect wrote:
I have a class
class A{
private Map fValues;
A(){
fValues= new HashMap();
prrotected class B {
B(){
fValues.get("String");
Above class is only for an example to expalin my problem.
Inner class B wants to access fValues from class A .
The eclipse gives me a warning
Access to enclosing method fValues from the type A is emulated by a synthetic accessor method. Increasing its visibility will improve your performance
I order to get rid of this warning I must make fValues public is this the only solution ?
miroWhat happens if you remove the modifier? (That is uses default)

Setting variables from inner class

I have a GUI that takes users information and provides a quotation as componants are clicked. My componants' Listeners are in seperate inner classes and from these I want to add certain details to variables, it seems to compile and run but it doesn't seem to be changing the value of the variable when the componants are clicked, is there any reason why this happens, my code is below:
public class MyGUI extends JFrame{
        public MyGUI(){
          //GUI STUFF HERE
        double Price;
     private String total=calculate();
     public String calculate(){
          double aTotal=Price;
          return "$ " + aTotal;
     class MyListener implements ItemListener{
          public void itemStateChanged(ItemEvent evt){
               if(evt.getSource()==rad1) {
               Price=0.10;
               else if(evt.getSource()==rad2) {
               Price=0.12;
                    totalLab.setText(total);
}

shouldn't I also be able to access the outer classes methods? It doesn't seem to do this either.

JCX access from java class

Is it possible to access jcx from java class ?
from jpf i am calling java class which inturn calls jcx and
i am getting nullpointer exception at jcx call in java class
waiting for solution...
thanks,
sridhar

Shrishar,
Unfortunately in the current release controls cannot be accessed from stand
alone java classes. You can create a custom control which can invoke the jcx
and be invoked from within the jpf.
Regards,
Raj Alagumalai
Backline Workshop Support
"sridhar" <[email protected]> wrote in message
news:4083d449$[email protected]..
>
Is it possible to access jcx from java class ?
from jpf i am calling java class which inturn calls jcx and
i am getting nullpointer exception at jcx call in java class
waiting for solution...
thanks,
sridhar

Local variable accessed within inner class

Hey everybody,
My program keeps telling me that it wont work because one of my methods is calling a local variable inside an inner class. Does anyone know what this means and how to fix it?
Heres the code:
public class SliderExample extends JPanel{
int value=0;
public SliderExample(int imw, int imh, Image img, BufferedImage buf, Graphics2D biCon){
super(true);
this.setLayout(new BorderLayout());
JSlider slider= new JSlider(JSlider.HORIZONTAL,0,imw,25);
slider.setMinorTickSpacing(10);
slider.setMajorTickSpacing(100);
slider.setPaintTicks(true);
slider.setPaintLabels(true);
JButton redraw= new JButton("Scroll");
redraw.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent ev){
reDraw(slider,img,buf,biCon,imw,imh);
add(slider,BorderLayout.CENTER);
add(redraw,BorderLayout.AFTER_LINE_ENDS);
public void reDraw(JSlider slid, Image im, BufferedImage bf, Graphics2D biC, int iw, int ih){
value=slid.getValue();
Graphics g= getGraphics();
g.drawImage(im,value,0,iw,ih,this);
g.drawImage(bf,value,0,iw,ih,this);
biC.drawImage(bf,value,0,iw,ih,this);
Any ideas???
THanks,
Rick

Its getting them from another class thats calling the mothod to construct the slider bar with dedraw button. Thats a pretty big class but I will post the code where I called the method:
public class Process extends JFrame implements MouseListener, MouseMotionListener{
private int [][] points;
private int [] lengths={0};
private int [] bin;
private String imstr;
private String imsav;
private int imgw=658;
private int imgh=512;
private int xArrayPos=0;
private int yArrayPos=0;
private int xpos=0;
private int ypos=0;
private int xprev;
private int yprev;
private int xadd;
private int yadd;
private String filstr;
Image image;
SimpleGUI gui;
BufferedImage buffer;
Graphics2D biContext;
Graphics2D g2;
BufferedImage last;
Graphics2D lastContext;
public Process(){
JFrame slideFrame = new JFrame("Please slide to scroll image");
slideFrame.setContentPane(new SliderExample(imgw, imgh,image,buffer,biContext));
slideFrame.pack();
slideFrame.setVisible(true);
Thats what anything having to do with that function in the other class that calls the Slider Class.
Do you know how I can fix this??
Thanks,
Rick

Flash Vars is not working when we accessing from other class files

Hi all, I'm currently developing a flex application where i
need to pass the data from the flash vars to the other class files
instead of the main actionscript class file.
Does any body know how i should go about doing that?? you can
see this below code : please help me out if u know how to solve
testnew2.as file
package {
import flash.display.Sprite;
import flash.display.LoaderInfo;
public dynamic class testnew2 extends Sprite {
public var
xmlfile:String=String(root.loaderInfo.parameters.lists);
public function testnew ():void{
package {
import flash.text.TextField;
import flash.display.Sprite;
import flash.display.LoaderInfo;
public dynamic class testnew extends testnew2 {
public function testnew () {
var myText:TextField = new TextField();
// this assumes that you are going to pass in an id variable
// on the end of the myFile.swf?id=12345 or
// use FlashVars in the HTML parameter list for instance
// 'FlashVars', 'id=123456', 'width', '1024',
myText.text = new testnew2().xmlfile;
addChild(myText);
but if we access in same file it is working fine:
package {
import flash.text.TextField;
import flash.display.Sprite;
import flash.display.LoaderInfo;
public dynamic class testnew extends Sprite {
public function testnew () {
var myText:TextField = new TextField();
myText.text = String(root.loaderInfo.parameters.lists);
addChild(myText);

Pass the data into the main app, then from there either pass
it into the sub-components or use
Application.application.parameters, or bind to the values.
Tracy

JSF backing bean accessibility from external class

I am using JSF in my application. Consider i am assigning a value of the inputtext field to a string in my managed bean. This bean has the getters and setters for the string.
Now my requirement is to get the value of the string i.e. the string value entered in the input text field in another class file. If "A" is a backing bean, I want a class B to access the values(in this case the inputtext value) from A.
Thanks in Advance.

Below is the code where i am using the inputtext tag in the JSP page
<h:inputText value="#{person.name}" />
"person" is the backing bean which is declared in the faces-config.xml
PersonBean code:*
package jsfExample;
public class PersonBean {
     private String name;
public void setName(String name) {
          this.name = name;
public String getName() {
          return this.name;
Now i have another class in the same package as shown below.
package jsfExample;
public class worker extends PersonBean{
//this function should use the variable name present in the backing bean//
     public void access(){
     PersonBean person= new PersonBean();
     String str=person.getName();
     System.out.println(str);
//I am getting null value in the str variable inside here//
but if i print the variable inside the backing bean(*PersonBean*) it is working fine.

JavaFX accessing Java Inner Classes

We have LOTS of common Java classes that look like this...
public class X {
    public class Y {
        public static final String Z = "ZzZZZzzZzzZzzZz";
}So in JAVA we can access them like this...
public String z = X.Y.Z;But in JavaFX I CAN'T do this...
var z : X.Y.Z;The compiler says +"non-static class com.myproject.X.Y cannot be referenced from a static context"+
Tell me it aint so, please :)

Galien, I doubt AndrewHughes can / want to change all the existing Java classes...
I tried to reproduce (I did) and found a workaround...
Java class (X.java):
public class X
    public static final String ZX = "ZzZZZzzZzzZzzZzXX";
    public class Y
        public static final String ZY = "ZzZZZzzZzzZzzZzYY";
    public static void main(String[] args)
      new A();
class A
A()
    System.out.println(X.Y.ZY);
}OK, it works...
JavaFX code: var z = X.Y.Z;(and not var z: X.Y.Z; since Z isn't a type...) Error "+non-static class X.Y cannot be referenced from a static context+". Mmmm...
Trying var z = X.ZX; works, of course.
Looking at the generated class files, I thought of a workaround: var z = X$Y.ZY;Yay! it works! :-D

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

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();
}

Access from inner class

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