Static variable not static

Hello
I've got a little problem.
I'm writing a Java program and I'm using five variables, all of them static Strings.
However, at runtime, only four of them are seen as static, the other one is non-static.
Can someone please explain why?
Thank you
later edit
Actually this is an open-source project and I'm trying to modify a class. Is it somehow possible that they ( as in the authors of the code ) 'locked' the classes so that nobody else could modify them ? Every time I'm trying to add a method or a variable, I get a java.lang.NoSuchFieldError or java.lang.NoSuchMethodError. If this is possible, how is this done?
Edited by: Nenea_Zap on May 22, 2010 11:02 AM

OK, I tried it using the all-platforms JMF zip.
I compiled successfully given the code you pointed to, unmodified.
Then I added this to the class you mentioned:
public int phony_number = 15;and was still able to compile successfully.
The only issue in both cases was that the compiler complained about raw types (non-use of generics).
I'd suggest creating a new project area, download the code clean, then confirm that you can compile it.
Then clean the code out -- delete all class files and any jar files that are created as part of building -- make your modification, and compile again.
If there's a problem post the compiler errors.
My hunch is that you were compiling, with old version of class files in the classpath, confusing the compiler.

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// Header file
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Thanks

thanks for your answer, You are right there is 2 foo singleton at different memory addresses.
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Hi,
I've created a program using swing components
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non-static variable this cannot be referenced from a
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done anything different from programs that have compiled
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Non static variable in static context

import java.util.Scanner;
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     String action = ("R");
     Scanner scan = new Scanner(System.in);
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          return faceValue1;
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It means what it says -- that you're trying to use a non-static thing (like a method or a field) from a static thing (like your main method).
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If you want to do the latter, then try this: make your main method instantiate a method, and run it, like this:
public static void main(String[] argv) {
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    game.play();
}Then create a method called play:
public void play() {
// put everything that's currently in main() in here
}See if that fixes it for you.

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I have the inclination to make every method
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Easy examples...
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Any AWT or Swing element that has color, font, text etc.
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chance.
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Hi Hans,
In Cocoa and Objective-C a static variable needs to be declared in the implementation file and not the header as you would normally do. Standard C variables can be set at the same time as the declaration but Cocoa objects need an extra step.
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static NSArray *count;
@implementation TestObject
- (id) init {
self = [super init];
if (self != nil) {
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// the 'if' statement ensures it is only set once
if (!count) {
count = [[NSArray arrayWithObjects:@"One",@"Two",@"Three",Nil] retain];
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@end
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Martin.
PowerMac G5 1.6Ghz Mac OS X (10.4.9) 4 gig RAM & NVidia 6800 Ultra

Static variables and JAR files problem

Hello All,
I am trying to get two applets to communicate.
Both are held in the same JAR file loaded from the same location. The JAR file also contains a class with some static variables which are used to comunicate between the two applets.
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Can anyone tell me why static variables stop working when the code is loaded from a JAR file.
Thanks in advance,
Alastair.

Ok,
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java.security.AccessControlException: access denied (java.util.PropertyPermission java.home read)
at java.security.AccessControlContext.checkPermission(Unknown Source)
at java.security.AccessController.checkPermission(Unknown Source)
at java.lang.SecurityManager.checkPermission(Unknown Source)
at java.lang.SecurityManager.checkPropertyAccess(Unknown Source)
at java.lang.System.getProperty(Unknown Source)
at sun.plugin.security.PluginClassLoader.getPermissions(Unknown Source)
at java.security.SecureClassLoader.getProtectionDomain(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at sun.applet.AppletClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
at appSend.init(appSend.java:62)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
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height = "300"
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What is static variable.

What is static variable. what is difference between static variable and public variable?

Static variables belong to the Class. Non-static variables belong to Class instances.
Public variables can be accessed from outside of the Package. Non-public variables can only be accessed within the Package.
So they are quite different thing. You can have Static variables, Public Static variables, and Private Static variables...

A basic question about static variables and methods

What would be the effects if I declare lots of static variables and static methods in my class?
Would my program run faster?
Would the class take more memory spaces? (If so, how do I estimate an appropriate number of variabls and methods to be declared static?)
Thank you @_@

when you declare a static var the var isn't created for every instance of the class, it just "live" in the class
when you declare a static method is the same, so if you have:
class MyClass
static int myMethod()
//Method work
you dont need to have a instance of the class to call myMethod, you can do such things like this.
int value = Myclass.myMethod();
if myMethod isn't static you can't do this.. so, if
class MyClass
int myMethod()
//Method work
you CAN'T call
int value = MyClass.myMethod();
instead, you have to write
MyClass m;
m = new MyClass();
value = m.myMethod();

When should I use static variable and when should not? Java essential

When should I use static variable and when should not? Java essential

Static => same value for all instances of the class.
Non-static => each instance can have its own value.
Which you need in which circumstances is completely up to you.

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I defined a Global class and I have a static variable. I could not see them as attribute in jConsole. BTW, the methods could seem in jconsole. And, I used the class includes static variables as a Global class.
How can i see the static variable in jconsole?

Global class is a final Class it is not be instantiated.
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Error on compile - non-static variable can not be referencedfrom static con

Error on compile happening with addButton?
Thanks
import java.awt.*;
import java.awt.event.*;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JFrame;
public class Log implements ActionListener {
JButton addButton;
public static void addComponentsToPane(Container pane) {
pane.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
     c.gridy = 3;
c.gridx = 0;
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pane.add(callsignLabel, c);
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c.gridx = 1;
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pane.add(nameLabel, c);
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c.gridx = 2;
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pane.add(timeLabel, c);
     c.gridy = 3;
c.gridx = 3;
     JLabel dateLabel= new JLabel("Date");
pane.add(dateLabel, c);
     c.gridy = 3;
c.gridx = 4;
     JLabel frequencyLabel= new JLabel("Freq ");
pane.add(frequencyLabel, c);
     c.gridy = 3;
c.gridx = 5;
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Thank you for the reply
I am new to Java
What is wrong with the way it is coded?The error message tells you what's wrong: You're trying to reference a non-static variable from a static context.
If you don't know what that means, then click the link I provided and look at the results from that google search. You might have to go through a few before you find a satisfactory explanation. And after you've done that, if you have specific questions about things you didn't understand there, please post again.

Using a static variable declared in an applet in another class

Hi guys,
I created an applet and i want to use one of the static variables declared in teh applet class in another class i have. however i get an error when i try to do that...
in my Return2 class i try to call the variable infoPanel (declared as a static JPanel in myApplet...myApplet is set up like so:
public class myApplet extends JApplet implements ActionListener, ListSelectionListener
here are some of the lines causing a problem in the Return2 class:
myApplet.infoPanel.removeAll();
myApplet.infoPanel.add(functionForm2.smgframeold);
myApplet.infoPanel.validate();
myApplet.infoPanel.repaint();
here are some of the errors i get
dummy/Return2.java [211:1] package myApplet does not exist
myApplet.infoPanel.removeAll();
^
dummy/Return2.java [212:1] package myApplet does not exist
myApplet.infoPanel.add(functionForm2.smgframeold);
^
dummy/Return2.java [213:1] package myApplet does not exist
myApplet.infoPanel.validate();
^
dummy/Return2.java [214:1] package myApplet does not exist
myApplet.infoPanel.repaint();
^
please help! thanks :)

I don't declare any packages though....i think it just doesn't recognize myApplet for some reason..
other errors i got compiling are:
dummy/Return2.java [82:1] cannot resolve symbol
symbol : variable myApplet
location: class Return2
updateDesc.setString(3, myApplet.staticName);
I Don't get why i'm getting this error cuase they worked fine when myApplet was a standalone application, not an applet.
myApplet is in the same folder as Return2 and it compiles properly.

Static variable not static

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