Inner class a composite data structure

I am currently working with a small project for my school. Since a class is a combination of data and functions, I consider a class as a data structure and when I use an inner class within a main class, I am combining two data structures and so it is an example for a composite data structure, am i correct, please help, thanks in advance ANY COMMENTS WELCOME . . .

Hi bobster and ianleslie,
Thanks for your replies, sorry if I had offended, since I was frustrated at seeing the reply.
OK, thanks a lot for one thing, that an inner class can be considered as a COMPOSITE relationship if it builds a relationship with outer class. That is great and that is what I was looking for. For example , please have a look at the following code fragment:
class UpdatePatient { //OUTER CLASS
......//ASSUME THAT THIS IS A MAIN SCREEN with two buttons update and exit
update.addActionListener(new ActionListener()
 public void actionPerformed(ActionEvent ev)
 System.out.println("Update Pressed");
 String item = m_List.getSelectedItem();
 int index = m_List.getSelectedIndex();
 ListNode[] nodes = (CreateLinkedList.getList()).toArray();
 CreateLinkedList.clear();
 String name = null;
 String add =null;
 String contact = null;
 for(int i =0; i< nodes.length; i++)
 if(i == index)
 name = m_Name.getText();
 String dob = m_DOB.getText();
 StringTokenizer st = new StringTokenizer(dob, "/");
 String day = st.nextToken();
 String month = st.nextToken();
 String year = st.nextToken();
 add = m_Address.getText();
 contact = m_Contact.getText();
 String sex = null;
 if(m_Male.getState() == false)
 sex = "Female";
 else
 sex = "Male";
 Patient pnew = new Patient(name,day,month,year,add,contact,sex);
 CreateLinkedList.insertAtExactPosition(pnew);
}//UPDATEPATIENT completes here
IS it not a clear representation of COMPOSITE DATA STRUCTURE? I think yes, OK? Thanks all again

Similar Messages

ABAP proxy class - data structure

I generated a ABAP Proxy Class and the data structure I want to use is put automatically under item structure which has 0...unbounded type.
1. How can I get rid of this item structure as it will create another unnecessary level for my mapping
2. If my source structure has only 3 level, and the target structure has more than 3 (including item), how to map it?
e.g.
Source structure: Level 1(occurrence 1) > Level 2(1)> Level 3(0..1)
Target structure: Level 1(1])--> Level 2(0...1) --> item (0..unbounded) ---> Level 4(0..1)
I need to map level 3 from my source to level 4 in target, but it didn't seem to work.
Thanks.

--->1. How can I get rid of this item structure as it will create another unnecessary level for my mapping
You can delete the proxy at Application Server.....make necessary changes at XI Message Interface and again generate the proxy...
-->Source structure: Level 1(occurrence 1) > Level 2(1)> Level 3(0..1)
Target structure: Level 1(1])--> Level 2(0...1) --> item (0..unbounded) ---> Level 4(0..1)
For this you need to make use of context change features of XI Mapping.
Regards,

Private inner classes

I'm trying to complete a "turn the lightbulb on and off" program, but when I try to draw circle2 in the
ButtonListener class I get an error message cannot find symbol. This is in reference to the Graphics
variable "page" created in the paintComponent method below. Shouldn't the inner class, private or
public inherit all data variables including objects from the parent class, in this case, the Bulb class? The code is below.
By the way, this IS NOT a school assignment so any help would be appreciated. I'm just trying to learn
this language.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Bulb extends JPanel
     private JButton push;
     private Circle circle, circle2;
     private final int DIAMETER = 100;
     private final int X = 10;
     private final int Y = 10;
     public Bulb()
          circle = new Circle(DIAMETER, Color.white, X,Y);
          circle2 = new Circle(DIAMETER, Color.yellow, X, Y); // to separate class
          push = new JButton("Turn on the Bulb");
          push.addActionListener(new ButtonListener());
          add(push);
          setPreferredSize(new Dimension(500, 500));
          setBackground(Color.black);
     public void paintComponent(Graphics page)
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          circle.draw(page);
private class ButtonListener implements ActionListener
          public void actionPerformed(ActionEvent event) //PROBLEM AREA. I GET ERROR MESSAGE STATING
// "CANNOT FIND SYMBOL" IN REFERENCE TO VARIABLE "PAGE."
// I THOUGHT THE INNER CLASS INHERITS ALL DATA FROM
// PARENT CLASS SUCH AS "PAGE."
               circle2.draw(page);
}

There are fields, which are associated with either a class or an object (and thus live in the heap in an object on the heap), and there are local variables, which are associated with methods and threads (i.e., a method invoked within a thread, and which thus live on the stack).
They're not the same thing.
You can't use a local variable in your paintComponent method in a different method.
Anyway you're designing your class wrong. Think model-view-controller. You have the model: a bunch of state and possibly behavior that represents the thing being seen, modified, and displayed. You have the view, which is how you see the model. And you have the controller, which modifies the model.
Your event handlers are part of the controller. They should change the model.
Your paintComponent method is part of the view.
So the event handlers should change some data, e.g., add a note that a circle should be displayed.
Then your paintComponent method should look at the data and act accordingly -- e.g., see that there's a circle to be displayed, and display it.

Inner Classes - when to use with Swing?

Hi again,
I was creating a GUI with JTabbedPane as content pane, while doing the single panes in the different tabs i started wondering about some design issues.
Let�s say you have a pane that is composed of 3 "subpanes" ( containing all the interaction components ). Should i write "normal" classes for each of the subpanes or is it more reasonable to define them as inner classes of the "main" panel - that�s at least what i thought because those 3 smaller panels are bound to the main panel for their lifetime...
Any design tips about inner classes and swing or even inner classes in general, i�d really appreciate.
Thx

The concept of inner classes design in java is (I hope) they provide 'composite aggregation' relation with the contained class.
Means that the (inner) class cannot exists alone and provide functionalities like other classes. Inner classes refer to the "contains" relationship in the UML.
The other regular associations say, having a value oject model to an UI are Structural Aggregation, means that the value object can be used in the UI and also separately.
For your case the inner classes are not suitable. You may have to find a suitable mechanism to get the individual tab panes. Probably use an interface to bridge the three tab panes and use an manager class, pass and id to the manager class and get the required Tabbed pane.
Thanks,
ananth
Hi again,
I was creating a GUI with JTabbedPane as content pane,
while doing the single panes in the different tabs i
started wondering about some design issues.
Let�s say you have a pane that is composed of 3
"subpanes" ( containing all the interaction components
). Should i write "normal" classes for each of the
subpanes or is it more reasonable to define them as
inner classes of the "main" panel - that�s at least
what i thought because those 3 smaller panels are
bound to the main panel for their lifetime...
Any design tips about inner classes and swing or even
inner classes in general, i�d really appreciate.
Thx

Why and how to use "inner class"

When i am learning advanced java language features,
i could not understand why and when to use the "inner class",
who can give me some examples?
Thanks!

You would use an inner class when an object needs visibility of the outer class. This is akin to a C++ friend.
An example of this is an iterator. An iterator over some collection is typically implemented as an inner class of the collection class. The API user asks for an Iterator (from the Collection) and gets one - in fact they receive an instance of an inner class, but doesn't care. The iterator needs to be inner, as the iterator needs to see the internal data structures of the outer (collection) class.
This could also be done with an anonymous class, as mentioned by spenhoet above. However, in the case of a collection, the role of the iterator is clear - thus it deserves its own class. And often there is more than one place an iterator can be returned (e.g. see java.util.List, which has several methods that return Iterators/ListIterators), thus it must be put in its own class to allow reuse of the code by outer class.

Extending vs. Using Data Structures

I'm fairly new to Java, though not to coding in general, and I'm wondering, whether its better to extend a data structure or to use one, when creating a class.
For example, I've been messing around with some playing cards, and to make the deck, I essentially want to use a stack. Would it be better to create a Deck class that extends Stack, or to create a Deck class that contains a Stack object and methods that modify the Stack? I've tried it both ways, and they both seem to do okay, but I'm wondering which way is preferable.
So far, inheriting seems more powerful, but using is much cleaner. (e.g. I don't have to worry about them calling pop() instead of draw())
Edited by: chess19 on Mar 16, 2009 6:19 PM

You seem to be on track in terms of the issues involved. If you google for the phrase "prefer composition to inheritance" you'll find a lot of people with relevant advice.

Non-final variable inside an inner class - my nemisis

I have an issue with accessing variables from an inner method. This structure seems to allow access to the text objects but not to the button object. This comes from a bit of example code that just illustrates a simple form window with text fields and buttons that read them.
At the start of the class I have text objects defined like this:
public class SimpleGUI extends Composite {
Text nameField;
Text junkField;
// Constructors come next, etc...
Later within this class there is a method to create some GUI stuff, and then to create a button and when pressed access and print the text to the console
protected void createGui(){
junkField = new Text(entryGroup,SWT.SINGLE); //Ross
junkField.setText("Howdy");
Button OKbutton = new Button(buttons,SWT.NONE);
OKbutton.setText("Ok");
OKbutton.addSelectionListener(
new MySelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
System.out.println("Name: " + nameField.getText());
System.out.println("Junk: " + junkField.getText());
And that all works fine. So within the inner class, the object junkField can be accessed nicely.
However if I try to do the same with the button (I want to change the label on the button after it's pressed) I get errors for trying to access a non-final object in an inner class.
I tried to handle the button similar to the text, adding this after the text defs:
Button myButton;
and under the println's in the inner class I wanted:
if OKbutton.getText.equals("OK") { OKbutton.setText("NotOK")}
That's when I get an issue with "cannot refer to a non-final variable inside an inside class defined in a different method"
Now, if I move the button declaration into the createGui method, and declare it with "final Button myButton" it works.
Why does the button need different treatment than the text?
Is this a suitable method to make my button change it's label when pressed, or is this sloppy?

Button is a local variable. The anonymous inner class object you create can continue to exist after the method ends, but the local variables will not. Therefore, as the error message says, you must make that local button variable final if you want to refer to it inside the anon inner class. If it's final, a copy of its value can be given to the inner class--there's no need to treat it as "variable."

OC4J: marshalling does not recreate the same data structure onthe client

Hi guys,
I am trying to use OC4J as an EJB container and have come across the following problem, which looks like a bug.
I have a value object method that returns an instance of ArrayList with references to other value objects of the same class. The value objects have references to other value objects. When this structure is marshalled across the network, we expect it to be recreated as is but that does not happen and instead objects get duplicated.
Suppose we have 2 value objects: ValueObject1 and ValueObject2. ValueObject1 references ValueObject2 via its private field and the ValueObject2 references ValueObject1. Both value objects are returned by our method in an ArrayList structure. Here is how it will look like (number after @ represents an address in memory):
Object[0] = com.cramer.test.SomeVO@1
Object[0].getValueObject[0] = com.cramer.test.SomeVO@2
Object[1] = com.cramer.test.SomeVO@2
Object[1].getValueObject[0] = com.cramer.test.SomeVO@1
We would expect to see the same (except exact addresses) after marshalling. Here is what we get instead:
Object[0] = com.cramer.test.SomeVO@1
Object[0].getValueObject[0] = com.cramer.test.SomeVO@2
Object[1] = com.cramer.test.SomeVO@3
Object[1].getValueObject[0] = com.cramer.test.SomeVO@4
It can be seen that objects get unnecessarily duplicated â“ the instance of the ValueObject1 referenced by the ValueObject2 is not the same now as the instance that is referenced by the ArrayList instance.
This does not only break referential integrity, structure and consistency of the data but dramatically increases the amount of information sent across the network. The problem was discovered when we found that a relatively small but complicated structure that gets serialized into a 142kb file requires about 20Mb of network communication. All this extra info is duplicated object instances.
I have created a small test case to demonstrate the problem and let you reproduce it.
Here is RMITestBean.java:
package com.cramer.test;
import javax.ejb.EJBObject;
import java.util.*;
public interface RMITestBean extends EJBObject
public ArrayList getSomeData(int testSize) throws java.rmi.RemoteException;
public byte[] getSomeDataInBytes(int testSize) throws java.rmi.RemoteException;
Here is RMITestBeanBean.java:
package com.cramer.test;
import javax.ejb.SessionBean;
import javax.ejb.SessionContext;
import java.util.*;
public class RMITestBeanBean implements SessionBean
private SessionContext context;
SomeVO someVO;
public void ejbCreate()
someVO = new SomeVO(0);
public void ejbActivate()
public void ejbPassivate()
public void ejbRemove()
public void setSessionContext(SessionContext ctx)
this.context = ctx;
public byte[] getSomeDataInBytes(int testSize)
ArrayList someData = getSomeData(testSize);
try {
java.io.ByteArrayOutputStream byteOutputStream = new java.io.ByteArrayOutputStream();
java.io.ObjectOutputStream objectOutputStream = new java.io.ObjectOutputStream(byteOutputStream);
objectOutputStream.writeObject(someData);
objectOutputStream.flush();
System.out.println(" serialised output size: "+byteOutputStream.size());
byte[] bytes = byteOutputStream.toByteArray();
objectOutputStream.close();
byteOutputStream.close();
return bytes;
} catch (Exception e) {
System.out.println("Serialisation failed: "+e.getMessage());
return null;
public ArrayList getSomeData(int testSize)
// Create array of objects
ArrayList someData = new ArrayList();
for (int i=0; i<testSize; i++)
someData.add(new SomeVO(i));
// Interlink all the objects
for (int i=0; i<someData.size()-1; i++)
for (int j=i+1; j<someData.size(); j++)
((SomeVO)someData.get(i)).addValueObject((SomeVO)someData.get(j));
((SomeVO)someData.get(j)).addValueObject((SomeVO)someData.get(i));
// print out the data structure
System.out.println("Data:");
for (int i = 0; i<someData.size(); i++)
SomeVO tmp = (SomeVO)someData.get(i);
System.out.println("Object["+Integer.toString(i)+"] = "+tmp);
System.out.println("Object["+Integer.toString(i)+"]'s some number = "+tmp.getSomeNumber());
for (int j = 0; j<tmp.getValueObjectCount(); j++)
SomeVO tmp2 = tmp.getValueObject(j);
System.out.println(" getValueObject["+Integer.toString(j)+"] = "+tmp2);
System.out.println(" getValueObject["+Integer.toString(j)+"]'s some number = "+tmp2.getSomeNumber());
// Check the serialised size of the structure
try {
java.io.ByteArrayOutputStream byteOutputStream = new java.io.ByteArrayOutputStream();
java.io.ObjectOutputStream objectOutputStream = new java.io.ObjectOutputStream(byteOutputStream);
objectOutputStream.writeObject(someData);
objectOutputStream.flush();
System.out.println("Serialised output size: "+byteOutputStream.size());
objectOutputStream.close();
byteOutputStream.close();
} catch (Exception e) {
System.out.println("Serialisation failed: "+e.getMessage());
return someData;
Here is RMITestBeanHome:
package com.cramer.test;
import javax.ejb.EJBHome;
import java.rmi.RemoteException;
import javax.ejb.CreateException;
public interface RMITestBeanHome extends EJBHome
RMITestBean create() throws RemoteException, CreateException;
Here is ejb-jar.xml:
<?xml version = '1.0' encoding = 'windows-1252'?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN" "http://java.sun.com/dtd/ejb-jar_2_0.dtd">
<ejb-jar>
<enterprise-beans>
<session>
<description>Session Bean ( Stateful )</description>
<display-name>RMITestBean</display-name>
<ejb-name>RMITestBean</ejb-name>
<home>com.cramer.test.RMITestBeanHome</home>
<remote>com.cramer.test.RMITestBean</remote>
<ejb-class>com.cramer.test.RMITestBeanBean</ejb-class>
<session-type>Stateful</session-type>
<transaction-type>Container</transaction-type>
</session>
</enterprise-beans>
</ejb-jar>
And finally the application that tests the bean:
package com.cramer.test;
import java.util.*;
import javax.rmi.*;
import javax.naming.*;
public class RMITestApplication
final static boolean HARDCODE_SERIALISATION = false;
final static int TEST_SIZE = 2;
public static void main(String[] args)
Hashtable props = new Hashtable();
props.put(Context.INITIAL_CONTEXT_FACTORY, "com.evermind.server.rmi.RMIInitialContextFactory");
props.put(Context.PROVIDER_URL, "ormi://lil8m:23792/alexei");
props.put(Context.SECURITY_PRINCIPAL, "admin");
props.put(Context.SECURITY_CREDENTIALS, "admin");
try {
// Get the JNDI initial context
InitialContext ctx = new InitialContext(props);
NamingEnumeration list = ctx.list("comp/env/ejb");
// Get a reference to the Home Object which we use to create the EJB Object
Object objJNDI = ctx.lookup("comp/env/ejb/RMITestBean");
// Now cast it to an InventoryHome object
RMITestBeanHome testBeanHome = (RMITestBeanHome)PortableRemoteObject.narrow(objJNDI,RMITestBeanHome.class);
// Create the Inventory remote interface
RMITestBean testBean = testBeanHome.create();
ArrayList someData = null;
if (!HARDCODE_SERIALISATION)
// ############################### Alternative 1 ##############################
// ## This relies on marshalling serialisation ##
someData = testBean.getSomeData(TEST_SIZE);
// ############################ End of Alternative 1 ##########################
} else
// ############################### Alternative 2 ##############################
// ## This gets a serialised byte stream and de-serialises it ##
byte[] bytes = testBean.getSomeDataInBytes(TEST_SIZE);
try {
java.io.ByteArrayInputStream byteInputStream = new java.io.ByteArrayInputStream(bytes);
java.io.ObjectInputStream objectInputStream = new java.io.ObjectInputStream(byteInputStream);
someData = (ArrayList)objectInputStream.readObject();
objectInputStream.close();
byteInputStream.close();
} catch (Exception e) {
System.out.println("Serialisation failed: "+e.getMessage());
// ############################ End of Alternative 2 ##########################
// Print out the data structure
System.out.println("Data:");
for (int i = 0; i<someData.size(); i++)
SomeVO tmp = (SomeVO)someData.get(i);
System.out.println("Object["+Integer.toString(i)+"] = "+tmp);
System.out.println("Object["+Integer.toString(i)+"]'s some number = "+tmp.getSomeNumber());
for (int j = 0; j<tmp.getValueObjectCount(); j++)
SomeVO tmp2 = tmp.getValueObject(j);
System.out.println(" getValueObject["+Integer.toString(j)+"] = "+tmp2);
System.out.println(" getValueObject["+Integer.toString(j)+"]'s some number = "+tmp2.getSomeNumber());
// Print out the size of the serialised structure
try {
java.io.ByteArrayOutputStream byteOutputStream = new java.io.ByteArrayOutputStream();
java.io.ObjectOutputStream objectOutputStream = new java.io.ObjectOutputStream(byteOutputStream);
objectOutputStream.writeObject(someData);
objectOutputStream.flush();
System.out.println("Serialised output size: "+byteOutputStream.size());
objectOutputStream.close();
byteOutputStream.close();
} catch (Exception e) {
System.out.println("Serialisation failed: "+e.getMessage());
catch(Exception ex){
ex.printStackTrace(System.out);
The parameters you might be interested in playing with are HARDCODE_SERIALISATION and TEST_SIZE defined at the beginning of RMITestApplication.java. The HARDCODE_SERIALISATION is a flag that specifies whether Java serialisation should be used to pass the data across or we should rely on OC4J marshalling. TEST_SIZE defines the size of the object graph and the ArrayList structure. The bigger this size is the more dramatic effect you get from data duplication.
The test case outputs the structure both on the server and on the client and prints out the size of the serialised structure. That gives us sufficient comparison, as both structure and its size should be the same on the client and on the server.
The test case also demonstrates that the problem is specific to OC4J. The standard Java serialisation does not suffer the same flaw. However using the standard serialisation the way I did in the test case code is generally unacceptable as it breaks the transparency benefit and complicates interfaces.
To run the test case:
1) Modify provider URL parameter value on line 15 of the RMITestApplication.java for your environment.
2) Deploy the bean to the server.
4) Run RMITestApplication on a client PC.
5) Compare the outputs on the server and on the client.
I hope someone can reproduce the problem and give their opinion, and possibly point to the solution if there is one at the moment.
Cheers,
Alexei

Hi,
Eugene, wrong end user recovery. Alexey is referring to client desktop end user recovery which is entirely different.
Alexy - As noted in the previous post:
http://social.technet.microsoft.com/Forums/en-US/bc67c597-4379-4a8d-a5e0-cd4b26c85d91/dpm-2012-still-requires-put-end-users-into-local-admin-groups-for-the-purpose-of-end-user-data?forum=dataprotectionmanager
Each recovery point has users permisions tied to it, so it's not possible to retroacively give the users permissions. Implement the below and going forward all users can restore their own files.
This is a hands off solution to allow all users that use a machine to be able to restore their own files.
1) Make these two cmd files and save them in c:\temp
2) Using windows scheduler – schedule addperms.cmd to run daily – any new users that log onto the machine will automatically be able to restore their own files.
<addperms.cmd>
Cmd.exe /v /c c:\temp\addreg.cmd
<addreg.cmd>
set users=
echo Windows Registry Editor Version 5.00>c:\temp\perms.reg
echo [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft Data Protection Manager\Agent\ClientProtection]>>c:\temp\perms.reg
FOR /F "Tokens=*" %%n IN ('dir c:\users\*. /b') do set users=!users!%Userdomain%\\%%n,
echo "ClientOwners"=^"%users%%Userdomain%\\bogususer^">>c:\temp\perms.reg
REG IMPORT c:\temp\perms.reg
Del c:\temp\perms.reg
Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. Regards, Mike J. [MSFT]
This posting is provided "AS IS" with no warranties, and confers no rights.

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);
}

Urgent! Need help in deciding data structure to use

Hi all,
I need to implement a restaurant system by which a customer can make a reservation.
I was wondering whether vector would be able to be store such an object, The thing is I don't want a complex data structure. just sumthin simple cos i hardly have anytime left to my submission. sighz...
The thing is I need to able to search based on 2 properties of an object. Eg. I need to search for a reservation based on the customer name and the date he reserved a table.
But I am totally clueless how to search thru a vector based on 2 properties of the object... Would really appreciate some help. Like an example how to so so based on my program. Feelin so lost...This is all I have so far:
class AddReservation
 static BufferedReader stdin = new BufferedReader (new InputStreamReader(System.in));
 //Main Method
 public static void main (String[]args)throws IOException
 String custName, comments;
 int covers, date, startTime, endTime;
 int count = 0;
 //User can only add one reservation at a time
 do
 //Create a new reservation
 Reservation oneReservation=new Reservation();
 System.out.println("Please enter customer's name:");
 System.out.flush();
 custName = stdin.readLine();
 oneReservation.setcustName(custName);
 System.out.println("Please enter number of covers:");
 System.out.flush();
 covers = Integer.parseInt(stdin.readLine());
 oneReservation.setCovers(covers);
 System.out.println("Please enter date:");
 System.out.flush();
 date = Integer.parseInt(stdin.readLine());
 oneReservation.setDate(date);
 System.out.println("Please enter start time:");
 System.out.flush();
 startTime = Integer.parseInt(stdin.readLine());
 oneReservation.setstartTime(startTime);
 System.out.println("Please enter end time:");
 System.out.flush();
 endTime = Integer.parseInt(stdin.readLine());
 oneReservation.setendTime(endTime);
 System.out.println("Please enter comments, if any:");
 System.out.flush();
 comments = stdin.readLine();
 oneReservation.setComments(comments);
 count++;
 while (count<1);
 class Reservation
 private Reservation oneReservation;
 private String custName, comments;
 private int covers, startTime, endTime, date;
 //Default constructor
 public Reservation()
 public Reservation(String custName, int covers, int date, int startTime, int endTime, String comments)
 this.custName=custName;
 this.covers=covers;
 this.date=date;
 this.startTime=startTime;
 this.endTime=endTime;
 this.comments=comments;
 //Setter methods
 public void setcustName(String custName)
 this.custName=custName;
 public void setCovers(int covers)
 this.covers=covers;;
 public void setDate(int date)
 this.date=date;
 public void setstartTime(int startTime)
 this.startTime=startTime;
 public void setendTime(int endTime)
 this.endTime=endTime;
 public void setComments(String comments)
 this.comments=comments;
 //Getter methods
 public String getcustName()
 return custName;
 public int getCovers()
 return covers;
 public int getDate()
 return date;
 public int getstartTime()
 return startTime;
 public int getendTime()
 return endTime;
 public String getComments()
 return comments;
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
class searchBooking
 static BufferedReader stdin = new BufferedReader (new InputStreamReader(System.in));
 public static void main (String[]args)throws IOException
 int choice, date, startTime;
 String custName;
 //Search Menu
 System.out.println("Search By: ");
 System.out.println("1. Date");
 System.out.println("2. Name of Customer");
 System.out.println("3. Date & Name of Customer");
 System.out.println("4. Date & Start time of reservation");
 System.out.println("5. Date, Name of customer & Start time of reservation");
 System.out.println("Please make a selection: ");
 //User keys in choice
 System.out.flush();
 choice = Integer.parseInt(stdin.readLine());
 if (choice==1)
 System.out.println("Please key in Date (DDMMYY):");
 System.out.flush();
 date = Integer.parseInt(stdin.readLine());
 else if (choice==2)
 System.out.println("Please key in Name of Customer:");
 System.out.flush();
 custName = stdin.readLine();
 else if (choice==3)
 System.out.println("Please key in Date (DDMMYY):");
 System.out.flush();
 date = Integer.parseInt(stdin.readLine());
 System.out.println("Please key in Name of Customer:");
 System.out.flush();
 custName = stdin.readLine();
 else if (choice==4)
 System.out.println("Please key in Date (DDMMYY):");
 System.out.flush();
 date = Integer.parseInt(stdin.readLine());
 System.out.println("Please key in Start time:");
 System.out.flush();
 startTime = Integer.parseInt(stdin.readLine());
 else if (choice==5)
 System.out.println("Please key in Date (DDMMYY):");
 System.out.flush();
 date = Integer.parseInt(stdin.readLine());
 System.out.println("Please key in Name of Customer:");
 System.out.flush();
 custName = stdin.readLine();
 System.out.println("Please key in Start time:");
 System.out.flush();
 startTime = Integer.parseInt(stdin.readLine());
 }

Please stop calling your questions urgent. Everybody's question is urgent to them. Nobody's are urgent to the people who are going to answer them. Calling your questions urgent suggests that you think they are more important than others' (They're not.) and will only serve to irritate those who would help you. It won't get your questions answered any sooner.

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

A robust data structure for a histogram of events over time.

Hi all,
I've been thinking for days, I am still lost on how to solve the following:
Let's say that we have a list of events that occur over a certain time interval. Each event has a start timestamp and a finish timestamp. The events occur in no particular order and expand over various length of periods.
With respect to the histogram, we mark the time period of an event occuring with a frequency of one. When events overlap over a time period, we mark that time period with a frequency of number of overlapping events.
Given this raw data, we want to examine the data's frequency under various granularity such as second, minutes, hours, days, weeks, month and years for 60sec, 60min, 24 hrs, 7 days, 4 wks ranges respectively.
So, what is a good intermediate (general) data structure that can store all the various events such that they can be easily transformed to a specific granularity. My goal here is to read the event list once, and histogram of events data with respect to various timeframe can be calculated.
Does a timeline like data strucuture that stores aggregated frequencies solve my problem? With a fine granuarlity say seconds and a long time range, the data structure will bound to overflow.
Any help is greatly appreciated!
Brian

You data structure would be in terms of Classes. You need a class Anevent{
String eventName;
Date startTime;
Date endTime;
In your main program have a Vector object which can store unllimited objects and which would not overflow. Store your event objects as they happen in this Vector. After your time interval of events is completed and you have the final Vector, you can pass the vector object to various methods in your main program to be simple or pass it to specailized graph drawing classes you would have to write to draw various Histograms.

Efficient data structure to implement simple text editor?

I was given this problem in an interview:
What data structure would you use to implement a simple text editor that does these 4 functions:
a) goto(line number)
b) insert(char input,location)
c) delete(location)
d) printAll() //print entire file
Given that i'm such a newb, i was stumped. I came up with making a 2d array that would allow for o(1) time for goto, but o(n) for everything else (shifting everything in the array). there were other downfalls too dealing with space issues and such, but he wanted me to optimize this data structure. I then came up with a linked list of arrays, but that had similar problems.
But thinking about it further is driving me a little crazy so I'm wondering if you guys have any suggestions on how to answer this question...
one thing that came to mind after is to implement the data structure as a binary tree, where each node contains
class Node
char theChar
int position; // ie 0 = first character in the file, and 81 could be the first character in the 2nd line
node left,right,parent;
}so how it works is the cursor would know where the location was so i would know where to delete and insert within the tree.
insert {
     //search for location to insert after (log n)
       //create new character node and append to current node
     //increment position for all subsequent children
delete(x) {
     search for x position
     if found, remove node and decrement position value for all children
goto(line #) {
     return line # * 80 (or whatever max length for a single line)
}the major problem i see here is balancing the tree after every insert/delete
Thanks in advance.

One of many great things emacs has given us is the gap buffer:
http://en.wikipedia.org/wiki/Gap_buffer
To see a Java implementation of this you can look in the Java SDK source. The document model (I forget exactly what its called), used in Swing uses a gap buffer.

Main method not found and how to put event handlers in an inner class

How would I put all the event handling methods in an inner class and I have another class that just that is just a main function, but when i try to run the project, it says main is not found. Here are the two classes, first one sets up everything and the second one is just main.
mport java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class JournalFrame extends JFrame {
private JLabel dateLabel = new JLabel("Date: ");
private JTextField dateField = new JTextField(20);
private JPanel datePanel = new JPanel(new FlowLayout());
BorderLayout borderLayout1 = new BorderLayout();
JPanel radioPanel = new JPanel();
JPanel statusPanel = new JPanel();
JPanel textAreaPanel = new JPanel();
JPanel buttonPanel = new JPanel();
GridLayout gridLayout1 = new GridLayout();
FlowLayout flowLayout1 = new FlowLayout();
GridLayout gridLayout2 = new GridLayout();
GridLayout gridLayout3 = new GridLayout();
JRadioButton personalButton = new JRadioButton();
JRadioButton businessButton = new JRadioButton();
JLabel status = new JLabel();
JTextArea entryArea = new JTextArea();
JButton clearButton = new JButton();
JButton saveButton = new JButton();
ButtonGroup entryType = new ButtonGroup();
public JournalFrame(){
try {
jbInit();
catch(Exception e) {
e.printStackTrace();
private void initWidgets(){
private void jbInit() throws Exception {
this.getContentPane().setLayout(borderLayout1);
radioPanel.setLayout(gridLayout1);
statusPanel.setLayout(flowLayout1);
textAreaPanel.setLayout(gridLayout2);
buttonPanel.setLayout(gridLayout3);
personalButton.setSelected(true);
personalButton.setText("Personal");
personalButton.addActionListener(new JournalFrame_personalButton_actionAdapter(this));
businessButton.setText("Business");
status.setText("");
entryArea.setText("");
entryArea.setColumns(10);
entryArea.setLineWrap(true);
entryArea.setRows(30);
entryArea.setWrapStyleWord(true);
clearButton.setPreferredSize(new Dimension(125, 25));
clearButton.setText("Clear Journal Entry");
clearButton.addActionListener(new JournalFrame_clearButton_actionAdapter(this));
saveButton.setText("Save Journal Entry");
saveButton.addActionListener(new JournalFrame_saveButton_actionAdapter(this));
this.setTitle("Journal");
gridLayout3.setColumns(1);
gridLayout3.setRows(0);
this.getContentPane().add(datePanel, BorderLayout.NORTH);
this.getContentPane().add(radioPanel, BorderLayout.WEST);
this.getContentPane().add(textAreaPanel, BorderLayout.CENTER);
this.getContentPane().add(buttonPanel, BorderLayout.EAST);
entryType.add(personalButton);
entryType.add(businessButton);
datePanel.add(dateLabel);
datePanel.add(dateField);
radioPanel.add(personalButton, null);
radioPanel.add(businessButton, null);
textAreaPanel.add(entryArea, null);
buttonPanel.add(clearButton, null);
buttonPanel.add(saveButton, null);
this.getContentPane().add(statusPanel, BorderLayout.SOUTH);
statusPanel.add(status, null);
this.pack();
setDefaultCloseOperation(EXIT_ON_CLOSE);
private void saveEntry() throws IOException{
if( personalButton.isSelected())
String file = "Personal.txt";
BufferedWriter bw = new BufferedWriter(new FileWriter(file,true));
entryArea.getText();
bw.write("Date: " + dateField.getText());
bw.newLine();
bw.write(entryArea.getText());
bw.newLine();
bw.flush();
bw.close();
status.setText("Journal Entry Saved");
else if (businessButton.isSelected())
String file = "Business.txt";
BufferedWriter bw = new BufferedWriter(new FileWriter(file,true));
bw.write("Date: " + dateField.getText());
bw.newLine();
bw.write(entryArea.getText());
bw.newLine();
bw.flush();
bw.close();
status.setText("Journal Entry Saved");
void clearButton_actionPerformed(ActionEvent e) {
dateField.setText("");
entryArea.setText("");
status.setText("");
void saveButton_actionPerformed(ActionEvent e){
try{
saveEntry();
}catch(IOException error){
status.setText("Error: Could not save journal entry");
void personalButton_actionPerformed(ActionEvent e) {
class JournalFrame_clearButton_actionAdapter implements java.awt.event.ActionListener {
JournalFrame adaptee;
JournalFrame_clearButton_actionAdapter(JournalFrame adaptee) {
this.adaptee = adaptee;
public void actionPerformed(ActionEvent e) {
adaptee.clearButton_actionPerformed(e);
class JournalFrame_saveButton_actionAdapter implements java.awt.event.ActionListener {
JournalFrame adaptee;
JournalFrame_saveButton_actionAdapter(JournalFrame adaptee) {
this.adaptee = adaptee;
public void actionPerformed(ActionEvent e) {
adaptee.saveButton_actionPerformed(e);
class JournalFrame_personalButton_actionAdapter implements java.awt.event.ActionListener {
JournalFrame adaptee;
JournalFrame_personalButton_actionAdapter(JournalFrame adaptee) {
this.adaptee = adaptee;
public void actionPerformed(ActionEvent e) {
adaptee.personalButton_actionPerformed(e);
public class JournalApp {
public static void main(String args[])
JournalFrame journal = new JournalFrame();
journal.setVisible(true);
}

Bet you're trying "java JournalFrame" when you need to "java JournalApp".
Couple pointers toward good code.
1) Use white space (extra returns) to separate your code into logical "paragraphs" of thought.
2) Add comments. At a minimum a comment at the beginning should name the file, state its purpose, identify the programmer and date written. A comment at the end should state that you've reached the end. In the middle, any non-obvious code should be commented and closing braces or parens should have a comment stating what they close (if there is non-trivial separation from where they open).
Here's a sample:
// JournalFrame.java - this does ???
// saisoft, 4/18/03
// constructor
private void jbInit() throws Exception {
    this.getContentPane().setLayout(borderLayout1);
    radioPanel.setLayout(gridLayout1);
    statusPanel.setLayout(flowLayout1);
    textAreaPanel.setLayout(gridLayout2);
    buttonPanel.setLayout(gridLayout3);
    personalButton.setSelected(true);
    personalButton.setText("Personal");
    personalButton.addActionListener(new JournalFrame_personalButton_actionAdapter(this));
    businessButton.setText("Business");
    status.setText("");
    entryArea.setText("");
    entryArea.setColumns(10);
    entryArea.setLineWrap(true);
    entryArea.setRows(30);
    entryArea.setWrapStyleWord(true);
} // end constructor
// end JournalFrame.java3) What would you expect to gain from that inner class? It might be more cool, but would it be more clear? I give the latter (clarity) a lot of importance.

Main method not found and how to implement events in an inner class

How would I put all the event handling methods in an inner class and I have another class that just that is just a main function, but when i try to run the project, it says main is not found. Here are the two classes, first one sets up everything and the second one is just main.
mport java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class JournalFrame extends JFrame {
private JLabel dateLabel = new JLabel("Date: ");
private JTextField dateField = new JTextField(20);
private JPanel datePanel = new JPanel(new FlowLayout());
BorderLayout borderLayout1 = new BorderLayout();
JPanel radioPanel = new JPanel();
JPanel statusPanel = new JPanel();
JPanel textAreaPanel = new JPanel();
JPanel buttonPanel = new JPanel();
GridLayout gridLayout1 = new GridLayout();
FlowLayout flowLayout1 = new FlowLayout();
GridLayout gridLayout2 = new GridLayout();
GridLayout gridLayout3 = new GridLayout();
JRadioButton personalButton = new JRadioButton();
JRadioButton businessButton = new JRadioButton();
JLabel status = new JLabel();
JTextArea entryArea = new JTextArea();
JButton clearButton = new JButton();
JButton saveButton = new JButton();
ButtonGroup entryType = new ButtonGroup();
public JournalFrame(){
try {
jbInit();
catch(Exception e) {
e.printStackTrace();
private void initWidgets(){
private void jbInit() throws Exception {
this.getContentPane().setLayout(borderLayout1);
radioPanel.setLayout(gridLayout1);
statusPanel.setLayout(flowLayout1);
textAreaPanel.setLayout(gridLayout2);
buttonPanel.setLayout(gridLayout3);
personalButton.setSelected(true);
personalButton.setText("Personal");
personalButton.addActionListener(new JournalFrame_personalButton_actionAdapter(this));
businessButton.setText("Business");
status.setText("");
entryArea.setText("");
entryArea.setColumns(10);
entryArea.setLineWrap(true);
entryArea.setRows(30);
entryArea.setWrapStyleWord(true);
clearButton.setPreferredSize(new Dimension(125, 25));
clearButton.setText("Clear Journal Entry");
clearButton.addActionListener(new JournalFrame_clearButton_actionAdapter(this));
saveButton.setText("Save Journal Entry");
saveButton.addActionListener(new JournalFrame_saveButton_actionAdapter(this));
this.setTitle("Journal");
gridLayout3.setColumns(1);
gridLayout3.setRows(0);
this.getContentPane().add(datePanel, BorderLayout.NORTH);
this.getContentPane().add(radioPanel, BorderLayout.WEST);
this.getContentPane().add(textAreaPanel, BorderLayout.CENTER);
this.getContentPane().add(buttonPanel, BorderLayout.EAST);
entryType.add(personalButton);
entryType.add(businessButton);
datePanel.add(dateLabel);
datePanel.add(dateField);
radioPanel.add(personalButton, null);
radioPanel.add(businessButton, null);
textAreaPanel.add(entryArea, null);
buttonPanel.add(clearButton, null);
buttonPanel.add(saveButton, null);
this.getContentPane().add(statusPanel, BorderLayout.SOUTH);
statusPanel.add(status, null);
this.pack();
setDefaultCloseOperation(EXIT_ON_CLOSE);
private void saveEntry() throws IOException{
if( personalButton.isSelected())
String file = "Personal.txt";
BufferedWriter bw = new BufferedWriter(new FileWriter(file,true));
entryArea.getText();
bw.write("Date: " + dateField.getText());
bw.newLine();
bw.write(entryArea.getText());
bw.newLine();
bw.flush();
bw.close();
status.setText("Journal Entry Saved");
else if (businessButton.isSelected())
String file = "Business.txt";
BufferedWriter bw = new BufferedWriter(new FileWriter(file,true));
bw.write("Date: " + dateField.getText());
bw.newLine();
bw.write(entryArea.getText());
bw.newLine();
bw.flush();
bw.close();
status.setText("Journal Entry Saved");
void clearButton_actionPerformed(ActionEvent e) {
dateField.setText("");
entryArea.setText("");
status.setText("");
void saveButton_actionPerformed(ActionEvent e){
try{
saveEntry();
}catch(IOException error){
status.setText("Error: Could not save journal entry");
void personalButton_actionPerformed(ActionEvent e) {
class JournalFrame_clearButton_actionAdapter implements java.awt.event.ActionListener {
JournalFrame adaptee;
JournalFrame_clearButton_actionAdapter(JournalFrame adaptee) {
this.adaptee = adaptee;
public void actionPerformed(ActionEvent e) {
adaptee.clearButton_actionPerformed(e);
class JournalFrame_saveButton_actionAdapter implements java.awt.event.ActionListener {
JournalFrame adaptee;
JournalFrame_saveButton_actionAdapter(JournalFrame adaptee) {
this.adaptee = adaptee;
public void actionPerformed(ActionEvent e) {
adaptee.saveButton_actionPerformed(e);
class JournalFrame_personalButton_actionAdapter implements java.awt.event.ActionListener {
JournalFrame adaptee;
JournalFrame_personalButton_actionAdapter(JournalFrame adaptee) {
this.adaptee = adaptee;
public void actionPerformed(ActionEvent e) {
adaptee.personalButton_actionPerformed(e);
public class JournalApp {
public static void main(String args[])
JournalFrame journal = new JournalFrame();
journal.setVisible(true);
}

Here is the complete code (with crappy indentation) :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class JournalFrame extends JFrame {
    private JLabel dateLabel = new JLabel("Date: ");
    private JTextField dateField = new JTextField(20);
    private JPanel datePanel = new JPanel(new FlowLayout());
    BorderLayout borderLayout1 = new BorderLayout();
    JPanel radioPanel = new JPanel();
    JPanel statusPanel = new JPanel();
    JPanel textAreaPanel = new JPanel();
    JPanel buttonPanel = new JPanel();
    GridLayout gridLayout1 = new GridLayout();
    FlowLayout flowLayout1 = new FlowLayout();
    GridLayout gridLayout2 = new GridLayout();
    GridLayout gridLayout3 = new GridLayout();
    JRadioButton personalButton = new JRadioButton();
    JRadioButton businessButton = new JRadioButton();
    JLabel status = new JLabel();
    JTextArea entryArea = new JTextArea();
    JButton clearButton = new JButton();
    JButton saveButton = new JButton();
    ButtonGroup entryType = new ButtonGroup();
    public JournalFrame(){
        try {
            jbInit();
        catch(Exception e){
            e.printStackTrace();
    private void initWidgets(){
    private void jbInit() throws Exception {
        this.getContentPane().setLayout(borderLayout1);
        radioPanel.setLayout(gridLayout1);
        statusPanel.setLayout(flowLayout1);
        textAreaPanel.setLayout(gridLayout2);
        buttonPanel.setLayout(gridLayout3);
        personalButton.setSelected(true);
        personalButton.setText("Personal");
        personalButton.addActionListener(new JournalFrame_personalButton_actionAdapter(this));
        businessButton.setText("Business");
        status.setText("");
        entryArea.setText("");
        entryArea.setColumns(10);
        entryArea.setLineWrap(true);
        entryArea.setRows(30);
        entryArea.setWrapStyleWord(true);
        clearButton.setPreferredSize(new Dimension(125, 25));
        clearButton.setText("Clear Journal Entry");
        clearButton.addActionListener(new JournalFrame_clearButton_actionAdapter(this));
        saveButton.setText("Save Journal Entry");
        saveButton.addActionListener(new JournalFrame_saveButton_actionAdapter(this));
        this.setTitle("Journal");
        gridLayout3.setColumns(1);
        gridLayout3.setRows(0);
        this.getContentPane().add(datePanel, BorderLayout.NORTH);
        this.getContentPane().add(radioPanel, BorderLayout.WEST);
        this.getContentPane().add(textAreaPanel, BorderLayout.CENTER);
        this.getContentPane().add(buttonPanel, BorderLayout.EAST);
        entryType.add(personalButton);
        entryType.add(businessButton);
        datePanel.add(dateLabel);
        datePanel.add(dateField);
        radioPanel.add(personalButton, null);
        radioPanel.add(businessButton, null);
        textAreaPanel.add(entryArea, null);
        buttonPanel.add(clearButton, null);
        buttonPanel.add(saveButton, null);
        this.getContentPane().add(statusPanel, BorderLayout.SOUTH);
        statusPanel.add(status, null);
        this.pack();
        setDefaultCloseOperation(EXIT_ON_CLOSE);
    private void saveEntry() throws IOException{
        if( personalButton.isSelected()){
            String file = "Personal.txt";
            BufferedWriter bw = new BufferedWriter(new FileWriter(file,true));
            entryArea.getText();
            bw.write("Date: " + dateField.getText());
            bw.newLine();
            bw.write(entryArea.getText());
            bw.newLine();
            bw.flush();
            bw.close();
            status.setText("Journal Entry Saved");
        else if (businessButton.isSelected()){
            String file = "Business.txt";
            BufferedWriter bw = new BufferedWriter(new FileWriter(file,true));
            bw.write("Date: " + dateField.getText());
            bw.newLine();
            bw.write(entryArea.getText());
            bw.newLine();
            bw.flush();
            bw.close();
            status.setText("Journal Entry Saved");
    void clearButton_actionPerformed(ActionEvent e) {
        dateField.setText("");
        entryArea.setText("");
        status.setText("");
    void saveButton_actionPerformed(ActionEvent e){
        try{saveEntry();}catch(IOException error){
            status.setText("Error: Could not save journal entry");
    void personalButton_actionPerformed(ActionEvent e) {
    class JournalFrame_clearButton_actionAdapter implements java.awt.event.ActionListener {
    JournalFrame adaptee;
    JournalFrame_clearButton_actionAdapter(JournalFrame adaptee) {
        this.adaptee = adaptee;
    public void actionPerformed(ActionEvent e) {
        adaptee.clearButton_actionPerformed(e);
class JournalFrame_saveButton_actionAdapter implements java.awt.event.ActionListener {
    JournalFrame adaptee;
    JournalFrame_saveButton_actionAdapter(JournalFrame adaptee) {
        this.adaptee = adaptee;
    public void actionPerformed(ActionEvent e) {
        adaptee.saveButton_actionPerformed(e);
class JournalFrame_personalButton_actionAdapter implements java.awt.event.ActionListener {
    JournalFrame adaptee;
    JournalFrame_personalButton_actionAdapter(JournalFrame adaptee) {
        this.adaptee = adaptee;
    public void actionPerformed(ActionEvent e) {
        adaptee.personalButton_actionPerformed(e);
}BadLands

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