Passing a float from one class to another?

ok i have an app that i have started from scratch several times on. I have a xib file containing anywhere from 3 - 10 textfields. i want to be able to pass data input in those textFeilds to another xib to display in a label, but also i want to be able to use some of that data input to also do calculations with and display those answer in additional labels on the answer.xib . i have a separate class just to store the data (datastorage.h & .m) i can successfully pass data from view1 into the datastorage and backout to view2 when the user presses the calculate button. the problem im having is that in the data storage class when im doing my calculations im using a float to hold the answer. i cant seen to find a way to push that float value from datastorage to view2. i have been searching for about 3 days now trying different things, converting the float to NSString, using an NSString instead of a float. i keep getting yellow errors no matter what i try. i even just tired a few minutes ago setting a void and float in the appdelegate, i read one forum that said you can pass a float between several viewcontrollers that way but that didnt seen to work either. does anyone have any ideas i could try? or point me in the right direction?
thanks in advance!

Did you try using a NSNumber?

Similar Messages

How to pass a variable from one class to another class?

Hi,
Is it possible to pass a variable from one class to another? For e.g., I need the value of int a for calculation purpose in method doB() but I get an error <identifier> expected. What does the error mean? I know, it's a very, very simple question but once I learn this, I promise to remember it forever. Thank you.
class A {
int a;
int doA() {
      a = a + 1;
      return a;
class B {
int b;
A r = new A();
r.a; // error: <identifier> expected. What does that mean ?
int doB() {
     int c = b/a; // error: operator / cannot be applied to a
}Thank you!

elaine_g wrote:
I am wondering why does (r.a) give an error outside the method? What's the reason it only works when used inside the (b/r.a) maths function? This is illegal syntax:
class B {
int b;
A r = new A();
r.a; //syntax error
}Why? Class definition restricts what you can define within a class to a few things:
class X {
    Y y = new Y(); //defining a field -- okay
    public X() { //defining a constructor -- okay
    void f() { //defining a method -- okay
}... and a few other things, but you can't just write "r.a" there. It also makes no sense -- that expression by itself just accesses a field and does nothing with it -- why bother?
This is also illegal syntax:
int doB() {
      A r = new A();
      r.a; // error: not a statement
}Again, all "r.a" does on its own is access a field and do nothing with it -- a "noop". Since it has no effect, writing this indicates confusion on the part of the coder, so it classified as a syntax error. There is no reason to write that.

Passing a parameter from one class to another class in the same package

Hi.
I am trying to pass a parameter from one class to another class with in a package.And i am Getting the variable as null every time.In the code there is two classes.
i. BugWatcherAction.java
ii.BugWatcherRefreshAction.Java.
We have implemented caching in the front-end level.But according to the business logic we need to clear the cache and again have to access the database after some actions are happened.There are another class file called BugwatcherPortletContent.java.
So, we are dealing with three java files.The database interaction is taken care by the portletContent.java file.Below I am giving the code for the perticular function in the bugwatcherPortletContent.java:
==============================================================
public Object loadContent() throws Exception {
Hashtable htStore = new Hashtable();
JetspeedRunData rundata = this.getInputData();
String pId = this.getPorletId();
PortalLogger.logDebug(" in the portlet content: "+pId);
pId1=pId;//done by sraha
htStore.put("PortletId", pId);
htStore.put("BW_HOME_URL",CommonUtil.getMessage("BW.Home.Url"));
htStore.put("BW_BUGVIEW_URL",CommonUtil.getMessage("BW.BugView.Url"));
HttpServletRequest request = rundata.getRequest();
PortalLogger.logDebug(
"BugWatcherPortletContent:: build normal context");
HttpSession session = null;
int bugProfileId = 0;
Hashtable bugProfiles = null;
Hashtable bugData = null;
boolean fetchProfiles = false;
try {
session = request.getSession(true);
// Attempting to get the profiles from the session.
//If the profiles are not present in the session, then they would have to be
// obtained from the database.
bugProfiles = (Hashtable) session.getAttribute("Profiles");
//Getting the selected bug profile id.
String bugProfileIdObj = request.getParameter("bugProfile" + pId);
// Getting the logged in user
String userId = request.getRemoteUser();
if (bugProfiles == null) {
fetchProfiles = true;
if (bugProfileIdObj == null) {
// setting the bugprofile id as -1 indicates "all profiles" is selected
bugProfileIdObj =(String) session.getAttribute("bugProfileId" + pId);
if (bugProfileIdObj == null) {
bugProfileId = -1;
else {
bugProfileId = Integer.parseInt(bugProfileIdObj);
else {
bugProfileId = Integer.parseInt(bugProfileIdObj);
session.setAttribute(
("bugProfileId" + pId),
Integer.toString(bugProfileId));
//fetching the bug list
bugData =BugWatcherAPI.getbugList(userId, bugProfileId, fetchProfiles);
PortalLogger.logDebug("BugWatcherPortletContent:: got bug data");
if (bugData != null) {
Hashtable htProfiles = (Hashtable) bugData.get("Profiles");
} else {
htStore.put("NoProfiles", "Y");
} catch (CodedPortalException e) {
htStore.put("Error", CommonUtil.getErrMessage(e.getMessage()));
PortalLogger.logException
("BugWatcherPortletContent:: CodedPortalException!!",e);
} catch (Exception e) {
PortalLogger.logException(
"BugWatcherPortletContent::Generic Exception!!",e);
htStore.put(     "Error",CommonUtil.getErrMessage(ErrorConstantsI.GET_BUGLIST_FAILED));
if (fetchProfiles) {
bugProfiles = (Hashtable) bugData.get("Profiles");
session.setAttribute("Profiles", bugProfiles);
// putting the stuff in the context
htStore.put("Profiles", bugProfiles);
htStore.put("SelectedProfile", new Integer(bugProfileId));
htStore.put("bugs", (ArrayList) bugData.get("Bugs"));
return htStore;
=============================================================
And I am trying to call this function as it can capable of fetching the data from the database by "getbugProfiles".
In the new class bugWatcherRefreshAction.java I have coded a part of code which actually clears the caching.Below I am giving the required part of the code:
=============================================================
public void doPerform(RunData rundata, Context context,String str) throws Exception {
JetspeedRunData data = (JetspeedRunData) rundata;
HttpServletRequest request = null;
//PortletConfig pc = portlet.getPortletConfig();
//String userId = request.getRemoteUser();
/*String userId = ((JetspeedUser)rundata.getUser()).getUserName();//sraha on 1/4/05
String pId = request.getParameter("PortletId");
PortalLogger.logDebug("just after pId " +pId); */
//Calling the variable holding the value of portlet id from BugWatcherAction.java
//We are getting the portlet id here , through a variable from BugWatcherAction.java
/*BugWatcherPortletContent bgAct = new BugWatcherPortletContent();
String portletID = bgAct.pId1;
PortalLogger.logDebug("got the portlet ID in bugwatcherRefreshAction:---sraha"+portletID);*/
// updating the bug groups
Hashtable result = new Hashtable();
try {
request = data.getRequest();
String userId = ((JetspeedUser)data.getUser()).getUserName();//sraha on 1/4/05
//String pId = (String)request.getParameter("portletId");
//String pId = pc.getPorletId();
PortalLogger.logDebug("just after pId " +pId);
PortalLogger.logDebug("after getting the pId-----sraha");
result =BugWatcherAPI.getbugList(profileId, userId);
PortalLogger.logDebug("select the new bug groups:: select is done ");
context.put("SelectedbugGroups", profileId);
//start clearing the cache
ContentCacheContext cacheContext = getCacheContext(rundata);
PortalLogger.logDebug("listBugWatcher Caching - removing markup content - before removecontent");
// remove the markup content from cache.
PortletContentCache.removeContent(cacheContext);
PortalLogger.logDebug("listBugWatcher Caching-removing markup content - after removecontent");
//remove the backend content from cache
CacheablePortletData pdata =(CacheablePortletData) PortletCache.getCacheable(PortletCacheHelper.getUserHandle(((JetspeedUser)data.getUser()).getUserName()));
PortalLogger.logDebug("listBugWatcher Caching User: " +((JetspeedUser)data.getUser()).getUserName());
PortalLogger.logDebug("listBugWatcher Caching pId: " +pId);
if (pdata != null)
// User's data found in cache!
PortalLogger.logDebug("listBugWatcher Caching -inside pdata!=null");
pdata.removeObject(PortletCacheHelper.getUserPortletHandle(((JetspeedUser)data.getUser()).getUserName(),pId));
PortalLogger.logDebug("listBugWatcher Caching -inside pdata!=null- after removeObject");
PortalLogger.logDebug("listBugWatcher Caching -finish calling the remove content code");
//end clearing the cache
// after clearing the caching calling the data from the database taking a fn from the portletContent.java
PortalLogger.logDebug("after clearing cache---sraha");
BugWatcherPortletContent bugwatchportcont = new BugWatcherPortletContent();
Hashtable httable= new Hashtable();
httable=(Hashtable)bugwatchportcont.loadContent();
PortalLogger.logDebug("after making the type casting-----sraha");
Set storeKeySet = httable.keySet();
Iterator itr = storeKeySet.iterator();
while (itr.hasNext()) {
String paramName = (String) itr.next();
context.put(paramName, httable.get(paramName));
PortalLogger.logDebug("after calling the databs data from hashtable---sraha");
} catch (CodedPortalException e) {
PortalLogger.logException("bugwatcherRefreshAction:: Exception- ",e);
context.put("Error", CommonUtil.getErrMessage(e.getMessage()));
catch (Exception e) {
PortalLogger.logException("bugwatcherRefreshAction:: Exception- ",e);
context.put(     "Error",CommonUtil.getErrMessage(ErrorConstantsI.EXCEPTION_CODE));
try {
((JetspeedRunData) data).setCustomized(null);
if (((JetspeedRunData) data).getCustomized() == null)
ActionLoader.getInstance().exec(data,"controls.EndCustomize");
catch (Exception e)
PortalLogger.logException("bugwatcherRefreshAction", e);
===============================================================
In the bugwatcher Action there is another function called PostLoadContent.java
here though i have found the portlet Id but unable to fetch that in the bugWatcherRefreshAction.java . I am also giving the code of that function under the bugWatcherAction.Java
================================================
// Get the PortletData object from intermediate store.
CacheablePortletData pdata =(CacheablePortletData) PortletCache.getCacheable(PortletCacheHelper.getUserHandle(
//rundata.getRequest().getRemoteUser()));
((JetspeedUser)rundata.getUser()).getUserName()));
pId1 = (String)portlet.getID();
PortalLogger.logDebug("in the bugwatcher action:"+pId1);
try {
Hashtable htStore = null;
// if PortletData is available in store, get current portlet's data from it.
if (pdata != null) {
htStore =(Hashtable) pdata.getObject(     PortletCacheHelper.getUserPortletHandle(
((JetspeedUser)rundata.getUser()).getUserName(),portlet.getID()));
//Loop through the hashtable and put its elements in context
Set storeKeySet = htStore.keySet();
Iterator itr = storeKeySet.iterator();
while (itr.hasNext()) {
String paramName = (String) itr.next();
context.put(paramName, htStore.get(paramName));
bugwatcherRefreshAction bRefAc = new bugwatcherRefreshAction();
bRefAc.doPerform(pdata,context,pId1);
=============================================================
So this is the total scenario for the fetching the data , after clearing the cache and display that in the portal.I am unable to do that.Presently it is still fetching the data from the cache and it is not going to the database.Even the portlet Id is returning as null.
I am unable to implement that thing.
If you have any insight about this thing, that would be great .As it is very urgent a promt response will highly appreciated.Please send me any pointers or any issues for this I am unable to do that.
Please let me know as early as possible.
Thanks and regards,
Santanu Raha.

Have you run it in a debugger? That will show you exactly what is happening and why.

Passing a variable from one class to another

Hello:
I am new to java programming. I am developing an application in Java
At a particular JTextField call it jtf3, I am invoking Calendar application by clikcing a jbutton.
I would like to set text in jtf by obtaining the date clicked by the user. I am storing complete date string in the Calendar application during ActionPerformed event at Calendar Application level.
I do not know how to pass this string to calling frame as it does not listen to the button event happening at the Calendar Application.
Much appreciated
Thanks a lot for your time
regards

This is the application from which the I am calling the calendar application.
The method setDate set the date obtained from calendar class during actionperformed event.
The actionperfomed event from CalendarClass is pasted below as well.
Much appreciated
import javax.swing.JFrame;
import javax.swing.*;
import java.awt.event.*;
import java.util.*;
import java.awt.*;
public class TestDrive
public static void main(String[] args) {
DatePanelFrame dpf = new DatePanelFrame();
dpf.addWindowListener(new WindowAdapter( ) {
public void windowClosing(WindowEvent we) { System.exit(0); }
dpf.pack();
dpf.setVisible(true);
class DatePanelFrame extends JFrame {
JTextField djtf;
String dateInput;
public DatePanelFrame() {
setTitle("Date Panel");
setSize(100, 800);
setLocation(300, 100);
Container content = getContentPane();
JPanel datePanel = new JPanel();
JButton calButton = new JButton(".....");
datePanel.add(calButton, BorderLayout.SOUTH);
djtf = new JTextField(" ");
datePanel.add(djtf, BorderLayout.NORTH);
content.setLayout(new BorderLayout());
content.add(datePanel, BorderLayout.CENTER);
calButton.addActionListener(new ActionListener()
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JFrame fr = new CalendarClass();
fr.setSize(400, 400);
fr.setLocation(600, 100);
ObjCal oc = new ObjCal();
fr.setVisible(true);
public void setDate(String d)
djtf.setText(d);
repaint();
System.out.println(djtf.getText());
The ActionPerformed event from CalendarClass
jbtArray.addActionListener(new ActionListener()
public void actionPerformed(ActionEvent event)
if (event.getActionCommand() != " ")
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          yearSelected = jtfYear.getText();
          int intYearSelected = Integer.valueOf(yearSelected).intValue();
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          int intMonthSelected = getMonthNum(monthSelected);
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          dpf.setDate(dateSelected);

Pass RowSet from one class to another

Hi, i am trying to pass a rowset from one class to another but i keep getting the error messages:
method does not return a value
statement not reachable
Does anybody know why?
package project1;
import java.sql.SQLException;
public class readdata {
    public static void main(String[] args) {
        Class2 cl = new Class2();
        try {
        while (cl.openConnection().next()) {
            System.out.println(cl.openConnection().getInt("id") + "-");
        catch (SQLException se)
                System.out.println(se);
       // while (rs.next())
         //       System.out.println(rs.getInt("id") + "-");
         //       System.out.println(rs.getString("field1") + '\n');
package project1;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.sql.RowSet;
public class Class2 {
   private Connection conn;
    public Class2() {
        openConnection();
    public RowSet openConnection()
            try
                    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance();
                    conn = DriverManager.getConnection("jdbc:odbc:;DRIVER=Microsoft Access Driver (*.mdb);DBQ=D:\\test.mdb;PWD=","admin","");
                    Statement command = conn.createStatement();
                    RowSet rs = (RowSet)command.executeQuery("select * FROM testing");
                    return rs;
                    System.out.println("Connected To Access");
                    rs.close();
                    conn.close();
            catch (SQLException se)
                    System.out.println(se);
            catch (Exception ex)
                    System.out.println(ex);
}Thanks in advance
Message was edited by:
snipered2003
Message was edited by:
snipered2003

Hi snipered2003
I'm fairly new to java, so check out anything I say.
to me it appears that the code within your try block in the main method of readdata class can never throw a SQLException since the calls are to cl.openConnection() which catches any SQLException and does not throw it.
So one statement not reachable is the statement in the catch blockSystem.out.println(se);Second, the only return statement in your openConnection() method is inside the try block, whic means that if an exception is encountered there will be no RowSet returned by the method.
Secondly, the code in the try block in your Class2.openConnection() after the return statement will also never be reached.
You may need something like    public RowSet openConnection()
        RowSet rs = null;
        try
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance();
            conn = DriverManager.getConnection("jdbc:odbc:;DRIVER=Microsoft Access Driver (*.mdb);DBQ=D:\\test.mdb;PWD=","admin","");
            Statement command = conn.createStatement();
            rs = (RowSet)command.executeQuery("select * FROM testing");
            System.out.println("Connected To Access");
        catch (SQLException se)
            System.out.println(se);
        catch (Exception ex)
            System.out.println(ex);
        return rs;
    }But you will have to check for a null return value in the call to the method.
It also looks like the code in your main method, when these things are ironed out, will run an infinite loop, but I could be wrong on that.
I think (note: think) this part should be        RowSet rs = cl.openConnection()
        if (rs != null) {
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        }Anybody please correct me if I am wrong.
And I don't know where the conn.close would fit in this scheme of things.
Cheers, Darryl

Passing Variables from One Class to Another

Hello, I am new to Java Programming and I'm currently starting off by trying to build a simple application.
I need help to pass variables created in one class to another.
In my source package, I created 2 java classes.
1. Main.java
2. InputFileDeclared.java
InputFileDeclared reads numerical data from an external text file and store them as string variables within the main method while Main converts a text string into a number.
Hence, I would like to pass these strings variables from the InputFileDeclared class to the Main class so that they can be converted into numbers.
I hope somebody out there may enlighten me on this.
Thank you very much in advance!

Values are passed from method to method, rather than from class to class. In a case such as you describe the code of a method in Main will probably call a method in InputFileDeclared which will return the String you want. The method in Main stores that in a local variable and processes it. It really doesn't matter here which class the method is in.
You InputFileDeclared object probably contains "state" information in its fields such as the details of the file it's reading and how far it's got, but generally the calling method in Main won't need to know about this state, just the last data read.
So the sequence in the method in Main will be:
1) Create an new instance of InputFileDeclared, probably passing it the file path etc..
2) Repeatedly call a method on that instance to return data values, until the method signals that it's reached the end of file, e.g. by returning a null String.
3) Probably call a "close()" method on the instance, which you should have written to close the file.

How can I pass an exception from one thread to another thread

If I create a new class, that will extends the class Thread, the methode run() can not be use with the statement Throws Exeption .
The question now: Is there any possibility to pass an exception from one thread to another thread?
Thx.

It really depends on what you want to do with your exception. Is there some sort of global handler that will process the exceptions in some meaningful way? Unless you have that, there's not much point in throwing an exception in a thread, unless you simply want the stack trace generated.
Presuming that you have a global handler that can catch exceptions, nest your Exception subclass inside a RuntimeException:
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thx

Hi there,
As far as I could understand your question: The second frame is created when the button is pressed? If that is the case you obviously handle the event in some kind of a listener which gets the path and then creates the second frame.
public class MyFrame extends JFrame {
public void setPath(String path) {
this.path = path;
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Hope to be helpful,
astrognom

Moving Variable from one class to another.

I need to get a Variable from one class to another how would I do this?

Well this is a very tipical scehario for every enterprise application. You always create logger classes that generate log files for your application, as that is the only way to track errors in your system when its in the production enviorment.
Just create a simple class that acts as the Logger, and have a method in it that accepts a variable of the type that you are are trying to pass; most commonly a String; but can be overloaded to accept constom classes. e.g.
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writeToFile("< " + new Date() + " > " + message);
public void log(CustomClass queueEvent)
log("queue message was: " + queueEvent.getMessage() + " at: " + queueEven.getEventTime());
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Regards
Omer

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I have a common jar file which will communicate to the server for data validation purpose.But after validation it has to invoke different different jar file based on its response from the server.So, I might have a object which has to pass from the common jar file to a specific jar file.So, I like to know what will be the best procedure to achieve it.
Please help me out.

arpitak wrote:
Yes,jar file holds class files.one of class files wants to trigger a method of a class file which resides in different jar file.this is the situation I tried to describe.Let consider there are three jar files like JAR A,JAR B ,JAR C.Here JAR A is a common jar where other two jar could be used as a plug in. So based on the condition any one of them (JARS) will be triggered by the common jar(JAR A).this is the situation.The class file of JAR A will trigger some method or main method of the JAR B/JAR C.So,here how could I pass a object from one jar to another is my main question.
Is it clear now?
I need a solution for this very urgently.Are you looking for a plug-in framework? That is, dynamically discovering and loading plugins. I am not experienced in developing or using plugins. However Googling "java plugin" brings up JPF.
If you just have multiple jars that have different classes, the JVM will load the appropriate classes if it can find the jars through the standard classloader on the classpath or through a customer classloader.

Fire event from one class to another.

I have a Login JFrame class that allows users to enter username and password. I then have another JFrame class which will monitor when someone logs in. I am trying to get the username and password to appear on the monitor login frame text area when the user presses enter on the login frame.
I can get it ot work by passing the Monitor class into the Login classes constructor but I want to be able to open the classes separately.When I try to open separatley at present I get java.lang.NullPointerException
     at project.LoginGUI.actionPerformed(LoginGUI.java:70) which is referring to the following code:
if(listen.equals("OK")){
     GymMonitor.username.setText(username.getText());
Both classes are in the same package. What I want to know is how to fire an event from one class to another? when the class you are firing to is constructed separately.
I hope this question is not too verbose.
Thanks

Generally for something like this you would use a listener.
Your login window is its own entity--it has a user interface, and it gets some information which someone else could ask it for. It could even generate its own events, such as when the user presses "OK". You would first define an interface for anyone who wants to know when someone logs in:
public interface ILoginListener extends java.util.EventListener
public void login(LoginEvent event);
}You would then define the LoginEvent class to contain information like what the user entered for username and password. You could give your login dialog a couple of methods:
private Vector myListeners = new Vector();
public void addLoginListener(ILoginListener listener) {
    myListeners.add(listener);
public void removeLoginListener(ILoginListener listener) {
    myListeners.remove(listener);
protected void fireLogin(LoginEvent event) {
    for (Iterator it = myListeners.iterator(); it.hasNext(); ) {
      ILoginListener listener = (ILoginListener)it.next();
      listener.login(event);
}You'd have your login dialog call fireLogin every time the user logged in.
Then, you could implement ILoginListener in your monitor window:
public void login(LoginEvent event) {
    // now do something with the event you just got.
}All the code I put in here is really generic stuff. You'll write this kind of stuff hundreds of times probably during your career. I haven't tested it though.
Hope this helps. :)

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Hi gurus,
In my requirement i need to pass the values from one program to another program.
I am using SUBMIT statement . But , the program which i am calling has no selection screen.
So how can i pass the values?
Please help me ASAP.
Regards,
Bhanu.R

Export your internal tables or work areas to a memory id in ur program before u use submit.
Then in second pgm you have to import from memory id given above.
example.
EXPORT gs_header FROM gs_header to memory id 'HEADER'.
EXPORT gt_item FROM gt_item to memory id 'ITEM'.
SUBMIT YFIIN_DISHC_MAILREPORT EXPORTING LIST TO MEMORY AND RETURN.
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import gs_header TO gs_header from MEMORY id 'HEADER'.
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how can I pass the photos from one iphone to another?

Use the Beaming feature. See the info at the ? In iPhoto for iOS.

Calling a drawLine() from one class to another from an ActionEvent

I have several JPanel objects called and placed on a JFrame. The JFrame has a RadioButton group with radio buttons. If I select a radio button and call a drawLine() method from a JPanel, I receive a "NullPointerException". Is it not possible to call this graphic method from one class to another?
Thanks for any input you can provide.
John

Remember that each panel draws it's own current state. So you need the ActionPerformed to change the state in your target panel.
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.event.*;
public class PanelComm extends JPanel {
private SubPanelOne subPanelOne = new SubPanelOne();
private SubPanelTwo subPanelTwo = new SubPanelTwo();
public class SubPanelOne extends JPanel {
    public SubPanelOne () {
      setLayout ( new BorderLayout() );
      setBorder ( BorderFactory.createTitledBorder ( "SubPanel One" ) );
      Reactor     reactor    = new Reactor();
      ButtonGroup group      = new ButtonGroup();
      JPanel      radioPanel = new JPanel(new GridLayout(0, 1));
      JRadioButton buttonOne = new JRadioButton ( "One" );
      buttonOne.addActionListener ( reactor );
      group.add ( buttonOne );
      radioPanel.add ( buttonOne );
      JRadioButton buttonTwo = new JRadioButton ( "Two" );
      buttonTwo.addActionListener ( reactor );
      group.add ( buttonTwo );
      radioPanel.add ( buttonTwo );
      JRadioButton buttonThree = new JRadioButton ( "Three" );
      buttonThree.addActionListener ( reactor );
      group.add ( buttonThree );
      radioPanel.add ( buttonThree );
      add ( radioPanel ,BorderLayout.LINE_START );
    protected void paintComponent ( Graphics _g ) {
      super.paintComponent ( _g );
      Graphics2D g = (Graphics2D)_g;
      g.setRenderingHint ( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
public class SubPanelTwo extends JPanel {
    private JLabel text = new JLabel();
    public SubPanelTwo () {
      setLayout ( new BorderLayout() );
      setBorder ( BorderFactory.createTitledBorder ( "SubPanel Two" ) );
      text.setFont ( new Font ( "Verdana" ,Font.PLAIN ,30 ) );
      text.setHorizontalAlignment ( JLabel.CENTER );
      add ( text ,BorderLayout.CENTER );
    protected void paintComponent ( Graphics _g ) {
      super.paintComponent ( _g );
      Graphics2D g = (Graphics2D)_g;
      g.setRenderingHint ( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
    public void setChoice ( String cmd ) {
      text.setText ( cmd );
public class Reactor implements ActionListener {
    public void actionPerformed ( ActionEvent e ) {
      subPanelTwo.setChoice ( e.getActionCommand() );
public PanelComm () {
    setLayout ( new GridLayout ( 1 ,2 ) );
    add ( subPanelOne );
    add ( subPanelTwo );
// main
public static void main ( String[] args ) {
    JFrame f = new JFrame ( "Panel Communication" );
    f.setDefaultCloseOperation ( JFrame.EXIT_ON_CLOSE );
    f.getContentPane().add ( new PanelComm() ,BorderLayout.CENTER );
    f.setSize ( 320 ,120 );
    f.setVisible ( true );
} // main
}

Moving a method from one class to another issues

Hi, im new. Let me explain what i am trying to achieve. I am basically trying to move a method from one class to another in order to refactor the code. However every time i do, the program stops working and i am struggling. I have literally tried 30 times these last two days. Can some one help please? If shown once i should be ok, i pick up quickly.
Help would seriously be appreciated.
Class trying to move from, given that this is an extraction:
class GACanvas extends Panel implements ActionListener, Runnable {
private WorldMenuItems speedMenuItems, designMenuItemsPlantGrowth, designMenuItemsPlantCount;
     private WorldMenuItems designMenuItemsPlantEaten, designMenuItemsApproximatePopulation;
     private WorldMenuItems designMenuItemsEatersBorn,designMenuItemsMutationProbability;
     private WorldMenuItems designMenuItemsCrossoverProbability;
MenuBar getMenuBar() {
          menuBar = new MenuBar();
          addControlItemsToMenuBar();
          addSpeedItemsToMenuBar();
          addWorldDesignItemsToMenuBar();
          return menuBar;
This is the method i am trying to move (below)
public void itemsInsideWorldDesignMenu() {
          designMenuItemsPlantGrowth = new WorldMenuItems("Plants Grow",
                    new String[] { "In Rows", "In Clumps", "At Random",
                              "Along the Bottom", "Along the Edges" }, 1);
          designMenuItemsPlantCount = new WorldMenuItems("Number Of Plants",
                    new String[] { "50", "100", "150", "250", "500" }, 3);
          designMenuItemsPlantEaten = new WorldMenuItems("When a Plant is Eaten",
                    new String[] { "It grows back somewhere",
                              "It grows back nearby", "It's Gone" }, 0);
          designMenuItemsApproximatePopulation = new WorldMenuItems(
                    "Approximate Population", new String[] { "10", "20", "25",
                              "30", "40", "50", "75", "100" }, 2);
          designMenuItemsEatersBorn = new WorldMenuItems("Eaters are Born",
                    new String[] { "At the Center", "In a Corner",
                              "At Random Location", "At Parent's Location" }, 2);
          designMenuItemsMutationProbability = new WorldMenuItems(
                    "Mutation Probability", new String[] { "Zero", "0.25%", "0.5%",
                              "1%", "2%", "3%", "5%", "10%" }, 3);
          designMenuItemsCrossoverProbability = new WorldMenuItems(
                    "Crossover Probability", new String[] { "Zero", "10%", "25%",
                              "50%", "75%", "100%" }, 4);
Class Trying to move to:
class WorldMenuItems extends Menu implements ItemListener {
   private CheckboxMenuItem[] items;
   private int selectedIndex = -1;
   WorldMenuItems(String menuName, String[] itemNames) {
      this(menuName, itemNames, -1);
   WorldMenuItems(String menuName, String[] itemNames, int selected) {
      super(menuName);
      items = new CheckboxMenuItem[itemNames.length];
      for (int i = 0; i < itemNames.length; i++) {
         items[i] = new CheckboxMenuItem(itemNames);
add(items[i]);
items[i].addItemListener(this);
selectedIndex = selected;
if (selectedIndex < 0 || selectedIndex >= items.length)
selectedIndex = 1;
items[selectedIndex].setState(true);
     public int getSelectedIndex() {
          return selectedIndex;
public void itemStateChanged(ItemEvent evt) { // This works on other systems
CheckboxMenuItem newSelection = (CheckboxMenuItem)evt.getSource();
for (int i = 0; i < items.length; i++) {
if (newSelection == items[i]) {
items[selectedIndex].setState(false);
selectedIndex = i;
newSelection.setState(true);
return;

Ok i've done this. I am getting an error on the line specified. Can someone help me out and tell me what i need to do?
GACanvas
//IM GETTING AN ERROR ON THIS LINE UNDER NAME, SAYING IT IS NOT VISIBLE
WorldMenuItems worldmenuitems = new WorldMenuItems(name, null);
public MenuBar getMenuBar() {
          menuBar = new MenuBar();
          addControlItemsToMenuBar();
          addSpeedItemsToMenuBar();
          worldmenuitems.addWorldDesignItemsToMenuBar();
          return menuBar;
class WorldMenuItems extends Menu implements ItemListener {
     private WorldMenuItems speedMenuItems, designMenuItemsPlantGrowth, designMenuItemsPlantCount;
     private WorldMenuItems designMenuItemsPlantEaten, designMenuItemsApproximatePopulation;
     private WorldMenuItems designMenuItemsEatersBorn,designMenuItemsMutationProbability;
     private WorldMenuItems designMenuItemsCrossoverProbability;
     GACanvas gacanvas = new GACanvas(null);
   private CheckboxMenuItem[] items;
   private int selectedIndex = -1;
   WorldMenuItems(String menuName, String[] itemNames) {
      this(menuName, itemNames, -1);
   WorldMenuItems(String menuName, String[] itemNames, int selected) {
      super(menuName);
      items = new CheckboxMenuItem[itemNames.length];
      for (int i = 0; i < itemNames.length; i++) {
         items[i] = new CheckboxMenuItem(itemNames);
add(items[i]);
items[i].addItemListener(this);
selectedIndex = selected;
if (selectedIndex < 0 || selectedIndex >= items.length)
selectedIndex = 1;
items[selectedIndex].setState(true);
     public int getSelectedIndex() {
          return selectedIndex;
public void itemStateChanged(ItemEvent evt) { // This works on other systems
CheckboxMenuItem newSelection = (CheckboxMenuItem)evt.getSource();
for (int i = 0; i < items.length; i++) {
if (newSelection == items[i]) {
items[selectedIndex].setState(false);
selectedIndex = i;
newSelection.setState(true);
return;
public void itemsInsideWorldDesignMenu() {
     designMenuItemsPlantGrowth = new WorldMenuItems("Plants Grow",
               new String[] { "In Rows", "In Clumps", "At Random",
                         "Along the Bottom", "Along the Edges" }, 1);
     designMenuItemsPlantCount = new WorldMenuItems("Number Of Plants",
               new String[] { "50", "100", "150", "250", "500" }, 3);
     designMenuItemsPlantEaten = new WorldMenuItems("When a Plant is Eaten",
               new String[] { "It grows back somewhere",
                         "It grows back nearby", "It's Gone" }, 0);
     designMenuItemsApproximatePopulation = new WorldMenuItems(
               "Approximate Population", new String[] { "10", "20", "25",
                         "30", "40", "50", "75", "100" }, 2);
     designMenuItemsEatersBorn = new WorldMenuItems("Eaters are Born",
               new String[] { "At the Center", "In a Corner",
                         "At Random Location", "At Parent's Location" }, 2);
     designMenuItemsMutationProbability = new WorldMenuItems(
               "Mutation Probability", new String[] { "Zero", "0.25%", "0.5%",
                         "1%", "2%", "3%", "5%", "10%" }, 3);
     designMenuItemsCrossoverProbability = new WorldMenuItems(
               "Crossover Probability", new String[] { "Zero", "10%", "25%",
                         "50%", "75%", "100%" }, 4);
public void addWorldDesignItemsToMenuBar() {
     gacanvas = new GACanvas(null);
     itemsInsideWorldDesignMenu();
     Menu designMenuItems = new Menu("WorldDesign");
     designMenuItems.add(designMenuItemsPlantGrowth);
     designMenuItems.add(designMenuItemsPlantCount);
     designMenuItems.add(designMenuItemsPlantEaten);
     designMenuItems.add(designMenuItemsApproximatePopulation);
     designMenuItems.add(designMenuItemsEatersBorn);
     designMenuItems.add(designMenuItemsMutationProbability);
     designMenuItems.add(designMenuItemsCrossoverProbability);
     gacanvas.menuBar.add(designMenuItems);

Passing a float from one class to another?

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