Does session or servletContext method return a copy of instance?

does the getAttribute method of session or servletContext method return a copy of instance?
or the reference of an instance?
I believed they return a copy of an instance because we set the instance back to session or context again after we update it.
however, I happened to find that every instance return by getAttribute method has same hashcode. why?

Java is pass by value. The same instance is returned, but the reference is different.

Similar Messages

Why does the Java method ServletContext.getResourceAsStream return null with a know good path to an xsl file?

iPLANET ISSUE
Why does the Java method ServletContext.getResourceAsStream return null with a know good path to an xsl file?
CODE
ServletContext context = mpiCfg.getServletConfig().getServletContext();
// Debugging
out.print(context.getServerInfo()); // Get server info
out.print(“getRealPath = ” + context.getRealPath("WEB-INF/xsl/RedirectToAcs.xsl"));
String strXslName = "RedirectToAcs.xsl";
InputStream is = context.getResourceAsStream("WEB-INF/xsl/"+ strXslName);
TRACE FROM THE LOG
[26/Jul/2002:08:23:15] info ( 2868): [0][][ClearCommerceCcpaMpi][]getServerInfo() = iPlanet-WebServer-Enterprise/6.0, getRealPath() = C:\iPlanet\Servers\web-apps\ccpa\WEB-INF\xsl\RedirectToAcs.xsl
[26/Jul/2002:08:23:15] info ( 2868): [0][][ClearCommerceCcpaMpi][]strXslName = RedirectToAcs.xsl, is = null
[26/Jul/2002:08:23:15] info ( 2868): [1][][ClearCommerceCcpaMpi][16]ResourceAsStream is null
[26/Jul/2002:08:23:15] info ( 2868): [1][][ClearCommerceCcpaMpi][30]Problem reading XSL file.
DIRECTORY DUMP
C:\iPlanet\Servers\web-apps\ccpa\WEB-INF\xsl>dir
Volume in drive C has no label.
Volume Serial Number is 9457-EBF4
Directory of C:\iPlanet\Servers\web-apps\ccpa\WEB-INF\xsl
07/22/2002 05:54p <DIR> .
07/22/2002 05:54p <DIR> ..
07/22/2002 05:54p 3,086 RedirectToAcs.xsl
07/22/2002 05:54p 3,088 Response.xsl
2 File(s) 6,174 bytes
2 Dir(s) 1,797,405,696 bytes free

I think there's supposed to be a forward slash before WEB-INF.
InputStream is = context.getResourceAsStream("/WEB-INF/xsl/"+ strXslName);

When a Method Returns an Object, does it return a copy or a pointer?

When you have a method that returns an Object, is the Object returning a copy of the Object returned inside
of the Method or is it an Actual pointer to the Object inside of the method's coresponding Object?
so say you have an object ...
Class Something {
JLabel myLabel = new JLable("myLabel");
public JLabel getLabel() {
return myLabel;;
Something something = new Something();
JLable theLabel = something.getLabel()
theLable.setString("theLable");
so when I setString on the Object theLabel , am I going to change the value of myLabel inside of the Object something?

Yes, it returns a pointer.

Is not abstract and does not override abstract method tablechanged

I will remove all the gui code to make it shorter, but my problem lies with my InteractiveTableModelListener.
public class Meet extends JPanel{
private static void createAndShowGUI() {
        JFrame frame = new JFrame("MEET_dataTable");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(new Meet(), BorderLayout.CENTER);
        frame.pack();
        frame.setVisible(true);
public class InteractiveTableModelListener implements TableModelListener {
     public void TableChanged(TableModelEvent evt) {
if (evt.getType() == TableModelEvent.UPDATE) {
      int column = evt.getColumn();
      int row = evt.getFirstRow();
      dataTable.setColumnSelectionInterval(column + 1, column + 1);
      dataTable.setRowSelectionInterval(row, row);
class InteractiveRenderer extends DefaultTableCellRenderer {
protected int interactiveColumn;
public InteractiveRenderer(int interactiveColumn) {
      this.interactiveColumn = interactiveColumn;
public Component getTableCellRendererComponent(JTable dataTable,
     Object value, boolean isSelected, boolean hasFocus, int row,
     int column)
Component c = super.getTableCellRendererComponent(dataTable, value, isSelected, hasFocus, row, column);
   if (column == interactiveColumn && hasFocus) {
     if ((Meet.this.tableModel.getRowCount() - 1) == row &&
        !Meet.this.tableModel.hasEmptyRow())
         Meet.this.tableModel.addEmptyRow();
    highlightLastRow(row);
return c;
public void highlightLastRow(int row) {
     int lastrow = tableModel.getRowCount();
if (row == lastrow - 1) {
      dataTable.setRowSelectionInterval(lastrow - 1, lastrow - 1);
else {
      dataTable.setRowSelectionInterval(row + 1, row + 1);
     dataTable.setColumnSelectionInterval(0, 0);
public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
            UIManager.put("swing.boldMetal", Boolean.FALSE);
            createAndShowGUI();
}As i say, i have removed all the gui code to make it shorter, but in this code i create the table and add all the model to it. I am being returned with the error
Meet.InteractiveTableModelListener is not abstract and does not override abstract method tableChanged(javax.swing.event.TableModelEvent)in javax.swing.event.TableModelListener
what would be causing this error?
Cheers

Sorry, just figured out my silly error, the method is tableChanged not TableChanged.
cheers
TOPIC CLOSED
Edited by: nick2price on Sep 11, 2008 7:08 AM

...is not abstract and does not override abstract method compare

Why am I getting the above compile error when I am very clearly overriding abstract method compare (ditto abstract method compareTo)? Here is my code -- which was presented 1.5 code and I'm trying to retrofit to 1.4 -- followed by the complete compile time error. Thanks in advance for your help (even though I'm sure this is an easy question for you experts):
import java.util.*;
   This program sorts a set of item by comparing
   their descriptions.
public class TreeSetTest
   public static void main(String[] args)
      SortedSet parts = new TreeSet();
      parts.add(new Item("Toaster", 1234));
      parts.add(new Item("Widget", 4562));
      parts.add(new Item("Modem", 9912));
      System.out.println(parts);
      SortedSet sortByDescription = new TreeSet(new
         Comparator()
            public int compare(Item a, Item b)   // LINE CAUSING THE ERROR
               String descrA = a.getDescription();
               String descrB = b.getDescription();
               return descrA.compareTo(descrB);
      sortByDescription.addAll(parts);
      System.out.println(sortByDescription);
   An item with a description and a part number.
class Item implements Comparable
      Constructs an item.
      @param aDescription the item's description
      @param aPartNumber the item's part number
   public Item(String aDescription, int aPartNumber)
      description = aDescription;
      partNumber = aPartNumber;
      Gets the description of this item.
      @return the description
   public String getDescription()
      return description;
   public String toString()
      return "[descripion=" + description
         + ", partNumber=" + partNumber + "]";
   public boolean equals(Object otherObject)
      if (this == otherObject) return true;
      if (otherObject == null) return false;
      if (getClass() != otherObject.getClass()) return false;
      Item other = (Item) otherObject;
      return description.equals(other.description)
         && partNumber == other.partNumber;
   public int hashCode()
      return 13 * description.hashCode() + 17 * partNumber;
   public int compareTo(Item other)   // OTHER LINE CAUSING THE ERROR
      return partNumber - other.partNumber;
   private String description;
   private int partNumber;
}Compiler error:
TreeSetTest.java:25: <anonymous TreeSetTest$1> is not abstract and does not over
ride abstract method compare(java.lang.Object,java.lang.Object) in java.util.Com
parator
            public int compare(Item a, Item b)
                       ^
TreeSetTest.java:41: Item is not abstract and does not override abstract method
compareTo(java.lang.Object) in java.lang.Comparable
class Item implements Comparable
^
2 errors

According to the book I'm reading, if you merely take
out the generic from the code, it should compile and
run in v1.4 (assuming, of course, that the class
exists in 1.4). I don't know what book you are reading but that's certainly incorrect or incomplete at least. I've manually retrofitted code to 1.4, and you'll be inserting casts as well as replacing type references with Object (or the erased type, to be more precise).
These interfaces do exist in 1.4, and
without the generics.Exactly. Which means compareTo takes an Object, and you should change your overriding method accordingly.
But this raises a new question: how does my 1.4
compiler know anything about generics? It doesn't and it can't. As the compiler is telling you, those interfaces expect Object. Think about it, you want to implement one interface which declares a method argument type of Object, in several classes, each with a different type. Obviously all of those are not valid overrides.

Java.nio select() method return 0 in my client application

Hello,
I'm developing a simple chat application who echo messages
But my client application loop because the select() method return 0
This is my code
// SERVER
package test;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Set;
public class Server {
     private int port = 5001;
     public void work() {
          try {
               ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
               serverSocketChannel.configureBlocking(false);
               InetSocketAddress isa = new InetSocketAddress(port);
               serverSocketChannel.socket().bind(isa);
               Selector selector = Selector.open();
               serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
               System.out.println("Listing on "+port);
               while(selector.select()>0) {
                    Set keys = selector.selectedKeys();
                    for(Iterator i = keys.iterator(); i.hasNext();) {
                         SelectionKey key = (SelectionKey) i.next();
                         i.remove();
                         if (key.isAcceptable()) {
                              ServerSocketChannel keyChannel = (ServerSocketChannel)key.channel();
                              SocketChannel channel = keyChannel.accept();
                              channel.configureBlocking(false);
                              channel.register(selector, SelectionKey.OP_READ );
                         } else if (key.isReadable()) {
                              SocketChannel keyChannel = (SocketChannel) key.channel();
                              String m = Help.read(keyChannel );
                              Help.write(m.toUpperCase(), keyChannel );
          } catch (IOException e) {
               e.printStackTrace();
     public static void main(String[] args) {
          Server s = new Server();
          s.work();
// CLIENT
package test;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Set;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class Client extends JFrame {
     private String host = "localhost";
     private int port = 5001;
     private SocketChannel socketChannel;
     private Selector selector;
     public void work() {
          try {
               socketChannel = SocketChannel.open();
               socketChannel.configureBlocking(false);
               InetSocketAddress isa = new InetSocketAddress(host, port);
               socketChannel.connect(isa);
               selector = Selector.open();
               socketChannel.register(selector, SelectionKey.OP_CONNECT | SelectionKey.OP_READ );
               while(true) {
                    selector.select();
                    Set keys = selector.selectedKeys();
                    for(Iterator i = keys.iterator(); i.hasNext();) {
                         SelectionKey key = (SelectionKey) i.next();
                         i.remove();
                         if (key.isConnectable()) {
                              SocketChannel keyChannel = (SocketChannel) key.channel();
                              if (keyChannel.isConnectionPending()) {
                                   System.out.println("Connected "+keyChannel.finishConnect());
                         } else if (key.isReadable()) {
                              SocketChannel keyChannel = (SocketChannel) key.channel();
                              String m = Help.read(keyChannel);
                              display(m);
          } catch (IOException e) {
               e.printStackTrace();
     private void display(final String m) {
          SwingUtilities.invokeLater(new Runnable() {
               public void run() {
                    area.append(m+"\n");
                    textFieed.setText("");
     private void sendMessage(final String m) {
          Thread t = new Thread(new Runnable() {
               public void run() {
                    try {
                         Help.write(m, socketChannel);
                    } catch (IOException e) {
                         e.printStackTrace();
          t.start();
     public Client() {
          addWindowListener(new WindowAdapter() {
               public void windowClosing(WindowEvent e) {
                    System.exit(1);
          textFieed.addKeyListener(new KeyAdapter() {
               public void keyPressed(KeyEvent e) {
                    if (e.getKeyCode()== KeyEvent.VK_ENTER) {
                         String m = textFieed.getText();
                         sendMessage(m);
          area.setEditable(false);
          getContentPane().add(textFieed, "North");
          getContentPane().add(new JScrollPane(area));
          setBounds(200, 200, 400, 300);
          show();
     private String messageToSend;
     private JTextArea area = new JTextArea();
     JTextField textFieed = new JTextField();
     public static void main(String[] args) {
          Client s = new Client();
          s.work();
// HELPER CLASS
package test;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CharsetEncoder;
public class Help {
     private static Charset charset = Charset.forName("us-ascii");
     private static CharsetEncoder enc = charset.newEncoder();
     private static CharsetDecoder dec = charset.newDecoder();
     private static void log(String m) {
          System.out.println(m);
     public static String read(SocketChannel channel) throws IOException {
          log("*** start READ");
          int n;
          ByteBuffer buffer = ByteBuffer.allocate(1024);
          while((n = channel.read(buffer)) > 0) {
               System.out.println("     adding "+n+" bytes");
          log(" BUFFER REMPLI : "+buffer);
          buffer.flip();
          CharBuffer cb = dec.decode(buffer);
          log(" CHARBUFFER : "+cb);
          String m = cb.toString();
          log(" MESSAGE : "+m);
          log("*** end READ");
          //buffer.clear();
          return m;
     public static void write(String m, SocketChannel channel) throws IOException {
          log("xxx start WRITE");
          CharBuffer cb = CharBuffer.wrap(m);
          log(" CHARBUFFER : "+cb);
          ByteBuffer buffer = enc.encode(cb);
          log(" BUFFER ALLOUE REMPLI : "+buffer);
          int n;
          while(buffer.hasRemaining()) {
               n = channel.write(buffer);
          System.out.println(" REMAINING : "+buffer.hasRemaining());
          log("xxx end WRITE");

Here's the fix for that old problem. Change the work method to do the following
- don't register interest in things that can't happen
- when you connect register based on whether the connection is complete or pending.
- add the OP_READ interest once the connection is complete.
This doesn't fix all the other problems this code will have,
eg.
- what happens if a write is incomplete?
- why does my code loop if I add OP_WRITE interest?
- why does my interestOps or register method block?
For code that answers all those questions see my obese post Taming the NIO Circus
Here's the fixed up Client code
// CLIENT
package test
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Set;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class Client extends JFrame {
     private String host = "localhost";
     private int port = 5001;
     private SocketChannel socketChannel;
     private Selector selector;
     public void work() {
          try {
               socketChannel = SocketChannel.open();
               socketChannel.configureBlocking(false);
               InetSocketAddress isa = new InetSocketAddress(host, port);
               socketChannel.connect(isa);
               selector = Selector.open();
               int interest = 0;
               if(socketChannel.isConnected())interest = SelectionKey.OP_READ;
               else if(socketChannel.isConnectionPending())interest = SelectionKey.OP_CONNECT;
               socketChannel.register(selector, interest);
               while(true)
                    int nn = selector.select();
                    System.out.println("nn="+nn);
                    Set keys = selector.selectedKeys();
                    for(Iterator i = keys.iterator(); i.hasNext();)
                         SelectionKey key = (SelectionKey) i.next();
                         i.remove();
                         if (key.isConnectable())
                              SocketChannel keyChannel = (SocketChannel) key.channel();
                              System.out.println("Connected "+keyChannel.finishConnect());
                              key.interestOps(SelectionKey.OP_READ);
                         if (key.isReadable())
                              SocketChannel keyChannel = (SocketChannel) key.channel();
                              String m = Help.read(keyChannel);
                              display(m);
          } catch (IOException e) {
               e.printStackTrace();
     private void display(final String m) {
          SwingUtilities.invokeLater(new Runnable() {
               public void run() {
                    area.append(m+"\n");
                    textFieed.setText("");
     private void sendMessage(final String m) {
          Thread t = new Thread(new Runnable() {
               public void run() {
                    try {
                         Help.write(m, socketChannel);
                    } catch (IOException e) {
                         e.printStackTrace();
          t.start();
     public Client() {
          addWindowListener(new WindowAdapter() {
               public void windowClosing(WindowEvent e) {
                    System.exit(1);
          textFieed.addKeyListener(new KeyAdapter() {
               public void keyPressed(KeyEvent e) {
                    if (e.getKeyCode()== KeyEvent.VK_ENTER) {
                         String m = textFieed.getText();
                         sendMessage(m);
          area.setEditable(false);
          getContentPane().add(textFieed, "North");
          getContentPane().add(new JScrollPane(area));
          setBounds(200, 200, 400, 300);
          show();
     private String messageToSend;
     private JTextArea area = new JTextArea();
     JTextField textFieed = new JTextField();
     public static void main(String[] args) {
          Client s = new Client();
          s.work();

Product is not abstract and does not override abstract method

Received the following errors.
Product.java:3: Product is not abstract and does not override abstract method ge
tDisplayText() in Displayable
public class Product implements Displayable
^
Product.java:16: getDisplayText() in Product cannot implement getDisplayText() i
n Displayable; attempting to use incompatible return type
found : void
required: java.lang.String
public void getDisplayText()
^
2 errors
Code reads as follows
import java.text.NumberFormat;
public class Product implements Displayable
     private String code;
     private String description;
     private double price;
     public Product()
          this.code = "";
          this.description = "";
          this.price = 0;
public void getDisplayText()
String message =
"Code: " + code + "\n" +
"Description: " + description + "\n" +
"Price: " + this.getFormattedPrice() + "\n";
     public Product(String code, String description, double price)
          this.code = code;
          this.description = description;
          this.price = price;
     public void setCode(String code)
          this.code = code;
     public String getCode(){
          return code;
     public void setDescription(String description)
          this.description = description;
     public String getDescription()
          return description;
     public void setPrice(double price)
          this.price = price;
     public double getPrice()
          return price;
     public String getFormattedPrice()
          NumberFormat currency = NumberFormat.getCurrencyInstance();
          return currency.format(price);
Please help!

Received the following errors.
Product.java:3: Product is not abstract and does not
override abstract method ge
tDisplayText() in Displayable
public class Product implements Displayable
^
Product.java:16: getDisplayText() in Product cannot
implement getDisplayText() i
n Displayable; attempting to use incompatible return
type
found : void
required: java.lang.String
public void getDisplayText()
^
2 errors
Code reads as follows
Please use the code tags when posting code. There is a code button right above the text box where you enter your post. Click on it and put the code between the code tags.
These error messages are quite clear in telling what is wrong. You have an Interface called Displayable that specifies a method something like thispublic String getDisplayText() {But in your Product source code, you created thismethodpublic void getDisplayText() {The compiler is complaining because the methods are not the same.
You also need to return a String in the method probalby like thisreturn message;

Flex Data Services does not see remote methods in extended ColdFusion component.

I have created a remote service base component as a AModelService.cfc file. I extend that file to make my ModelService.cfc. When I configure the ColdFusion data service and point to ModelService.cfc and click next, I don't see any remote methods (there are none explicitly defined in the component) in the Service Operations window.
If I go back and point to AModelServide.cfc, the parent component, and hit next, I see all the remote methods that are defined in the parent component. So, either I am doing something wrong, or Data Services does not look at methods up the cfc prototype chain, which from an OOP standpoint means that instead of say creating one restful base class and being nice and DRY you can't. I.e. not OOP for data services. Is this a bug, or what?
Anybody get data services to work with extended service components?
Mark

Thanks for the reply. Yes, I did compile all the Java and it
works OK with a simple Java program. It just will not work in a
Flex application.
The java classes are:
RRA:
package blah.myPackage;
import java.util.List;
import java.util.Collection;
import flex.data.DataSyncException;
import flex.data.assemblers.AbstractAssembler;
class RRA extends AbstractAssembler
public Collection fill( List fillParameters )
RRS service = new RRS();
return service.getSome();
RRS:
package blah.myPackage;
import java.util.ArrayList;
import java.util.List;
import java.sql.*;
import flex.EORS.*;
class RRS
public List getSome()
ArrayList list = new ArrayList();
String str = "bob";
RR rr = new RR(str);
list.add(rr);
return list;
RR:
package blah.myPackage;
class RR
private String name;
public RR() { }
public RR(String name)
this.name = name;
public String getName()
return this.name;
public void setName(String name)
this.name = name;
I started with something that retrieved data from a database
but watered it down just to try and get some kind of communication
between Flex and Java.

The class of the deferred-methods return type "{0}" can not be found.

I am developing a multilingual portal application.
I have the method that changes the locale based on user's choice in the bean and the method is being referred to as below.
<af:selectOneChoice label="Select Language" autoSubmit="true"
value="#{localeBean.locale}"
valueChangeListener="localeBean.changeLocale">
<af:selectItem label="English" value="en" id="si1"/>
<af:selectItem label="French" value="fr" id="si2"/>
<af:selectItem label="Dutch" value="nl" id="si3"/>
</af:selectOneChoice>
when i try to run the application, i am getting compile time errors as below,
The class of the deferred-methods return type "{0}" can not be found.
No property editor found for the bean "javax.el.MethodExpression".
After going through the discussion forums i learned that the compilation errors can be resolved by setting the <jsp:directive.page deferredSyntaxAllowedAsLiteral="false> at the starting of the page.
Even after that i am getting the compilation error.
Any solutions, suggestions or possible approaches would be helpful as i am new to Webcenter Portal development.
Thanks,

The error you get points to a problem on the page (somewhere). Switch to source mode and check the right margin if you see orange or red marks. These are pointing to problems (not all are show stoppers, but they give you hints that something is not according to the standard for jsf, jsff, jsp or jspx pages.
Have you checked that the bean is correctly defined and that it's reachable?
Start a fresh page and isolate the problem, e.g. build a selectOneChoiuce on the new page (don't copy it as you might copy the error too) and make it work on the new page. Once you have it running you can compare the solution to your not running page.
Timo

Can a method return a class ?

hi,
i have a simple question.
can a method return class value ?
in the below script i did'nt understand the commented line.
package com.google.gwt.sample.stockwatcher.client;
import com.google.gwt.user.client.rpc.RemoteService;
import com.google.gwt.user.client.rpc.RemoteServiceRelativePath;
@RemoteServiceRelativePath("login")
public interface LoginService extends RemoteService {
public LoginInfo login(String requestUri); //What is this ? is this a sample of what i asked ?
}

The answer to your question is yes.
The idea is that an object calls a function of another object (passing in objects to the function as arguments) in which that object returns an object (note the arguments or returned value of the function may alternately be primitive types). Each object typically encapsulates data and provides a rich set of functions to the calling object so that calling object doesn't have to deal with the raw data directly. Therefore, not only does the calling object get the data it wants, but also a rich set of functions that can manipulate that data.
Example:
Book book = new Book();
int characterCount = book.getChapter(3).getParagraph(4).getSentence(12).getWord(8).getCharacterCount();
In the above, each object (Book, Chapter,Paragraph,Sentence,Word) has a rich set of functions it provides to its caller.
Example: the Sentence Object has a collection of word objects (raw data). Functions it provides to Paragraph object are:
Word getWord(int index), Words getWords(), int getWordCount().
If you haven't already done so, I suggest reading a book on Java from cover to cover to pick up such Object Oriented concepts.

Custom Login Module - Commit Method return TRUE always?

Hi,
I am creating a custom login module for my portal authentication.
For the login module, should the commit() method always return TRUE?
The example code on help.sap.com indicates yes to this question.
However, the JAVA Sun standard indicates that commit should return FALSE if the preceding login method returned FALSE.
Does the SAP example stray from the SUN standard? How should I code the commit() method such that it works (Always TRUE, or follow lead of login() method)?
Regards,
Kevin

Hi Kevin,
I'm actually working with this document: <a href="https://www.sdn.sap.comhttp://www.sdn.sap.comhttp://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/com.sap.km.cm.docs/library/events/webinars/jaas%20login%20module%20development%20on%20webas%20java%20640.pdf#search=%22classloader%20sda%20jar%20reference%22">JAAS Login Modules</a>.
There is also example code. If it should be ignored they return false, otherwise true (page 32).
Regards,
Marcus
Message was edited by: Marcus Freiheit

Java.lang.StackOverflowError when invoking a method, returning a org.w3c.dom.Document object, on a SessionBean

Hello,
I hope someone can help me with this.
I have a stateless session bean, which is returning a
org.w3c.dom.Document object. The whole object is getting created
but at the client side I am getting the following exception:
java.rmi.RemoteException: ; nested exception is:
weblogic.rmi.ServerError: A RemoteException occurred in the server method
- with nested exception:
[java.lang.StackOverflowError:
Start server side stack trace:
java.lang.StackOverflowError
at java.lang.Exception.<init>(Compiled Code)
at java.lang.reflect.InvocationTargetException.<init>(InvocationTargetEx
ception.java:58)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Compiled Code)
at java.io.ObjectOutputStream.invokeObjectWriter(Compiled Code)
at java.io.ObjectOutputStream.outputObject(Compiled Code)
at java.io.ObjectOutputStream.writeObject(Compiled Code)
at java.io.ObjectOutputStream.outputClassFields(Compiled Code)
at java.io.ObjectOutputStream.defaultWriteObject(Compiled Code)
Then multiple occurences of the last few lines followed by
at org.apache.xerces.dom.ParentNode.writeObject(Compiled Code)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Compiled Code)
at java.io.ObjectOutputStream.invokeObjectWriter(Compiled Code)
at java.io.ObjectOutputStream.outputObject(Compiled Code)
at java.io.ObjectOutputStream.writeObject(Compiled Code)
at java.io.ObjectOutputStream.outputClassFields(Compiled Code)
at java.io.ObjectOutputStream.defaultWriteObject(Compiled Code)
at org.apache.xerces.dom.ParentNode.writeObject(Compiled Code)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Compiled Code)
at java.io.ObjectOutputStream.invokeObjectWriter(Compiled Code)
at java.io.ObjectOutputStream.outputObject(Compiled Code)
at java.io.ObjectOutputStream.writeObject(Compiled Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeObject(Compiled
Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeSpecial(Compiled
Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeObject(Compiled
Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeObjectWL(Compiled
Code)
at weblogic.rmi.extensions.AbstractOutputStream2.writeObject(Compiled
Code)
at com.ssmb.teams.model.CMSInterestDataEJBEOImpl_WLSkel.invoke(Compiled
Code)
at weblogic.rmi.extensions.BasicServerObjectAdapter.invoke(Compiled Code
at weblogic.rmi.extensions.BasicRequestHandler.handleRequest(Compiled
Code)
at weblogic.rmi.internal.BasicExecuteRequest.execute(Compiled Code)
at weblogic.kernel.ExecuteThread.run(Compiled Code)
End server side stack trace
at weblogic.rmi.extensions.AbstractRequest.sendReceive(AbstractRequest.j
ava:76)
at com.ssmb.teams.model.CMSInterestDataEJBEOImpl_WLStub.getRegionAnalyst
Data(CMSInterestDataEJBEOImpl_WLStub.java:558)
at com.ssmb.teams.model.CMSInterestDataEJBEOImpl_ServiceStub.getRegionAn
alystData(CMSInterestDataEJBEOImpl_ServiceStub.java, Compiled Code)
at CMSJavaScript.main(CMSJavaScript.java:87)
The structure of the XML document is
<Maillist>
     <Region>
          <RegionCode>7</RegionCode>
          <RegionName>Asia Pacific</RegionName>
          <Analyst>
               <Id>11111</Id>
               <Name>AAAAAAAAAAAAAAAAA</Name>
          </Analyst>
          <Analyst>
               <Id>22222</Id>
               <Name>BBBBBBBBBBBBBBBBBB</Name>
          </Analyst>
     </Region>
</Maillist>
If the no. of Anlayst elements are 219, I am getting this error ( the same thing
is working for less no. of analyst).
Surprisingly when I access this ejb, by deploying it on my local server instance
on Win-NT, it works fine. I am getting this
exception, when the server is running on Sun Solaris.
The weblogic version is 5.1.
It will be really helpful if someone can reply to mee ASAP
Thanks.
Suren.

Thanks a lot guys for all that information.
Rajesh Mirchandani <[email protected]> wrote:
Suren,
More info at
http://edocs.bea.com/wls/docs60/faq/java.html#251197
Rob Woollen wrote:
The quick fix is probably to use the -Xss argument on the Solaris JVMto increase the
thread stack size.
-- Rob
Suren wrote:
Thanks for your quick response.
But how do we overcome with this?
I tried to look for some help with this, but if you have any idea,
can you suggest
something ?
Thanks
Suren.
Rob Woollen <[email protected]> wrote:
It looks like the stack is overflowing when your DOM Tree is being
serialized.
Perhaps the Solaris JVM has a lower stack size by default.
-- Rob
Suren wrote:
Hello,
I hope someone can help me with this.
I have a stateless session bean, which is returning a
org.w3c.dom.Document object. The whole object is getting created
but at the client side I am getting the following exception:
java.rmi.RemoteException: ; nested exception is:
weblogic.rmi.ServerError: A RemoteException occurred in
the
server method
- with nested exception:
[java.lang.StackOverflowError:
Start server side stack trace:
java.lang.StackOverflowError
at java.lang.Exception.<init>(Compiled Code)
at java.lang.reflect.InvocationTargetException.<init>(InvocationTargetEx
ception.java:58)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Compiled Code)
at java.io.ObjectOutputStream.invokeObjectWriter(Compiled
Code)
at java.io.ObjectOutputStream.outputObject(Compiled Code)
at java.io.ObjectOutputStream.writeObject(Compiled Code)
at java.io.ObjectOutputStream.outputClassFields(CompiledCode)
at java.io.ObjectOutputStream.defaultWriteObject(CompiledCode)
Then multiple occurences of the last few lines followed by
at org.apache.xerces.dom.ParentNode.writeObject(CompiledCode)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Compiled Code)
at java.io.ObjectOutputStream.invokeObjectWriter(CompiledCode)
at java.io.ObjectOutputStream.outputObject(Compiled Code)
at java.io.ObjectOutputStream.writeObject(Compiled Code)
at java.io.ObjectOutputStream.outputClassFields(CompiledCode)
at java.io.ObjectOutputStream.defaultWriteObject(CompiledCode)
at org.apache.xerces.dom.ParentNode.writeObject(CompiledCode)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Compiled Code)
at java.io.ObjectOutputStream.invokeObjectWriter(CompiledCode)
at java.io.ObjectOutputStream.outputObject(Compiled Code)
at java.io.ObjectOutputStream.writeObject(Compiled Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeObject(Compiled
Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeSpecial(Compiled
Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeObject(Compiled
Code)
at weblogic.common.internal.WLObjectOutputStreamBase.writeObjectWL(Compiled
Code)
at weblogic.rmi.extensions.AbstractOutputStream2.writeObject(Compiled
Code)
at com.ssmb.teams.model.CMSInterestDataEJBEOImpl_WLSkel.invoke(Compiled
Code)
at weblogic.rmi.extensions.BasicServerObjectAdapter.invoke(CompiledCode
at weblogic.rmi.extensions.BasicRequestHandler.handleRequest(Compiled
Code)
at weblogic.rmi.internal.BasicExecuteRequest.execute(CompiledCode)
at weblogic.kernel.ExecuteThread.run(Compiled Code)
End server side stack trace
at weblogic.rmi.extensions.AbstractRequest.sendReceive(AbstractRequest.j
ava:76)
at com.ssmb.teams.model.CMSInterestDataEJBEOImpl_WLStub.getRegionAnalyst
Data(CMSInterestDataEJBEOImpl_WLStub.java:558)
at com.ssmb.teams.model.CMSInterestDataEJBEOImpl_ServiceStub.getRegionAn
alystData(CMSInterestDataEJBEOImpl_ServiceStub.java, Compiled
Code)
at CMSJavaScript.main(CMSJavaScript.java:87)
The structure of the XML document is
<Maillist>
<Region>
<RegionCode>7</RegionCode>
<RegionName>Asia Pacific</RegionName>
<Analyst>
<Id>11111</Id>
<Name>AAAAAAAAAAAAAAAAA</Name>
</Analyst>
<Analyst>
<Id>22222</Id>
<Name>BBBBBBBBBBBBBBBBBB</Name>
</Analyst>
</Region>
</Maillist>
If the no. of Anlayst elements are 219, I am getting this error( the
same thing
is working for less no. of analyst).
Surprisingly when I access this ejb, by deploying it on my local
server
instance
on Win-NT, it works fine. I am getting this
exception, when the server is running on Sun Solaris.
The weblogic version is 5.1.
It will be really helpful if someone can reply to mee ASAP
Thanks.
Suren.

Help with Error: $host does not have a method 'messageBox'

Greetings Everyone:
I get this error in my Log window:
Error: $host does not have a method 'messageBox'
I'm calling xfa.host.messageBox("MyMessage") from form's initialize event.
What am I doing wroing?
Acrobat Pro 9 - Java Script is enabled.
Thanks in advance,
iL

Hi Steve:
Thanks for your prompt responses. I appreicate that. I got the latest version.
I'm OT on at home looking for more answers...I'm guessing it's an installation issue...
I even tried console.println("Message"); CTRL + J and blank. I did this on Acrobat and LC.
I'm gonna do a full unistnall and reinstall when I get back to office.
The software is coming from our IS dept so I know it's squeaky clean.
I did an Installer Repair but the problem has returned.
I also can't use/access any xfa.layout memebers....
I get this errors even on newly created forms...it hasn't crashed again so I can't get any bucket ID log yet.
Here's whats on my office box that giving me grief:
LC version 8.2.1.4029.1.523496
Acrobat Pro 9
Java Version 6 Update 15
OS Platform: (HP Box)
SQL Server 2008 Express (HotFix installed)
VS2008,Office2k7.
XP SP3
iL

Re: Error: $host does not have a method 'messageBox'

Hello Experts:
I'm experiencing strange behavior on my LC Designer ES application.
I recieve a warning and my console window (ctrl+j) doesn't show up nor does the message box.
I cannot see xfa.layout members on the object drop-down menu. I have re-installed to no avail.
This occurs on every all forms. The default script is set to JavaScript.
Can anyone explain this behavior. Is it an installation issue?
Thank you for your time, iL.
Log:
Generating PDF Document...
Script failed (language is javascript; context is xfa[0].form[0].form1[0])
script = xfa.host.messageBox("My Message");
Error: $host does not have a method 'messageBox'
PDF generated successfully.
Script:
form1::initialize - (JavaScript, client)
xfa.host.messageBox("My Message");
System Info:
LC version 8.2.1.4029.1.523496
Acrobat Pro 9
Java Version 6 Update 15
SQL Server 2008 Express (HotFix installed)
XP SP3, Office 2k7

Hi Steve:
Thanks for your prompt responses. I appreicate that. I got the latest version.
I'm OT on at home looking for more answers...I'm guessing it's an installation issue...
I even tried console.println("Message"); CTRL + J and blank. I did this on Acrobat and LC.
I'm gonna do a full unistnall and reinstall when I get back to office.
The software is coming from our IS dept so I know it's squeaky clean.
I did an Installer Repair but the problem has returned.
I also can't use/access any xfa.layout memebers....
I get this errors even on newly created forms...it hasn't crashed again so I can't get any bucket ID log yet.
Here's whats on my office box that giving me grief:
LC version 8.2.1.4029.1.523496
Acrobat Pro 9
Java Version 6 Update 15
OS Platform: (HP Box)
SQL Server 2008 Express (HotFix installed)
VS2008,Office2k7.
XP SP3
iL

LINQ to Entities does not recognize the method 'System.String ToString()'

Hi, i am working on MVC using LINQ query where i am heading a problem with LINQ Query. When I use following code
public ActionResult GetProduct()
Category p = new Category();
var all = db.Products.ToList();
// var catname = from i in db.Categories select i.CategoryID.ToString();
p.CategName = (from i in db.Categories select new SelectListItem {Value =i.CategoryID.ToString(), Text = i.CategoryName }).ToList();
var qq = (from i in db.Products join j in db.Categories on i.CategoryID equals j.CategoryID select new Product { ProductName = i.ProductName, UnitPrice = i.UnitPrice, UnitsOnOrder = i.UnitsOnOrder }).ToList();
p.Products = qq;
return View("GetProduct", p);
It throws an error
LINQ to Entities does not recognize the method 'System.String ToString(Int32)' method, and this method cannot be translated into a store expression.
kindly help to fix this problem.
Mayank Mani Pandey India

Entity Framework cannot convert ToString() to SQL. Create the object after you have fetched the results:
public ActionResult GetProduct()
Category p = new Category();
var all = db.Products.ToList();
// var catname = from i in db.Categories select i.CategoryID.ToString();
p.CategName = (from i in db.Categories select i).AsEnumerable().Select(x => new SelectListItem { Value = x.CategoryID.ToString(), Text = x.CategoryName }).ToList();
var qq = (from i in db.Products join j in db.Categories on i.CategoryID equals j.CategoryID select new Product { ProductName = i.ProductName, UnitPrice = i.UnitPrice, UnitsOnOrder = i.UnitsOnOrder }).ToList();
p.Products = qq;
return View("GetProduct", p);
Please remember to close your threads by marking all helpful posts as answer and then start a new thread if you have a new question.

Does session or servletContext method return a copy of instance?

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