What calls getTableCellRendererComponent() method????

I found a code for an interactive jTable which can be used to add and edit data into arraylist,
I'm trying to understand that code...
there is a class which is an subclass of the DefaultTableCellRenderer class
and it has a method with the folloing signature
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column)
in the whole code no object isn calling that,
Please tell me how this method get called
Thank you very much....
Edited by: Madushan.UoM on Mar 30, 2009 5:03 PM

in the whole code no object isn calling that,Then you have a bug in your code.
Read the Swing tutorial on "How to Use Tables" for a working example of creating a custom renderer. Or search the forum for examples.
Please tell me what are the other methods defaultly called when a jTable is created???Its not important to know the details, but if you really want to know then look at the code yourself. All the source code comes with the JDK you just need to unzip it. We are not going to do this for you.

Similar Messages

What are the parameters in Call transaction method?

Hi ABAPER'S,
Please give me what are the parameters in call transaction method?
Thanks,
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Processing batch input data with CALL TRANSACTION USING is the faster of the two recommended data transfer methods. In this method, legacy data is processed inline in your data transfer program.
Syntax:
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UPDATE <update>
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E
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A
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<Error_handling>.
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The UPDATE Parameter
You use the UPDATE parameter to specify how updates produced by a transaction should be processed. You can select between these modes:
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Return codes:
Value
Explanation
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Successful
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Name:
Explanation:
SY-MSGID
Message-ID
SY-MSGTY
Message type (E,I,W,S,A,X)
SY-MSGNO
Message number
SY-MSGV1
Message variable 1
SY-MSGV2
Message variable 2
SY-MSGV3
Message variable 3
SY-MSGV4
Message variable 4
Error Analysis and Restart Capability
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write out or save the message table
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Hi All,
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Thanks in advance.
Best Regards,
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http://forum.java.sun.com/thread.jsp?forum=421&thread=426771&tstart=0&trange=100

What class called my method?

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[email protected]
[email protected]

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Calling a method to a program

hello,
I have a requirement that I am working on, I need to create a program that will have vendor number and vendor bank account number on the selection screen.
Now what I need to do is I need to call a method from a class that will do some kind of validation, method name is 'validation'
My problem here is that method validation has only vendor bank account number as a parameter. Vendor number is defined as an attribute in the class, let's say z_vendor, and in the method we are using Z_vendor as a vendor number.
Can you please tell me how can I set the value of the attribute to the one that the user will enter using a FM and then how to call the method validation in to my program.
I can not make any change the way class has been declared.
The attribute z_vendor is defined as follows:
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2. Visibility - Public
I am very new to OOPS.. so any help will be really appreciated.

Hi Rahul,
You can do like this:
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LVOOP "call parent method" doesn't work when used in sibling VI

It seems to me that the "call parent method" doesn't work properly according to the description given in the LabVIEW help.
I have two basic OOP functions I am doing examples for. I can get one to work easily and the other one is impossible.
Background
There are 3 basic situations in which you could use the "call parent method"
You are calling the parent VI (or method) of a child VI from within the child VI
You are calling the parent VI (or method) of a child VI from within a sibling VI
You are calling the parent VI (or method) of a child VI from a different class/object.
From the LabVIEW help system for "call parent method":
Calls the nearest ancestor implementation of a class method. You can use the Call Parent Method node only on the block diagram of a member VI that belongs to a class that inherits member VIs from an ancestor class. The child member VI must be a dynamic dispatching member VI and have the same name as the ancestor member VI
From my reading of that it means situation 3 is not supported but 1 & 2 should be.
Unfortunately only Situation 1 works in LabVIEW 2012.
Here is what I want
And this is what I actually get
What this means is that I can perform a classic "Extend Method" where a child VI will use the parent's implementation to augment it's functions BUT I cannot perform a "Revert Method" where I call the parent method's implementation rather than the one that belongs to the object.
If you want a picture
Any time I try and make operation2 the VI with the "call parent method" it shows up for about 1/2 sec and then turns into operation.
So there are only 3 possibilities I can see
Bug
Neither situation 2 or 3 are intended to work (see above) and the help is misleading
I just don't know what I am doing (and I am willing to accept this if someone can explain it to me)
The downside is that if situation 2 above doesn't work it does make the "call parent node" much less usefull AND it's usage/application just doesn't make sense. You cannot just drop the "call parent node" on a diagram, it only works if you have an existing VI and you perform a replace. If you can only perform situation 1 (see above) then you should just drop the "call parent node" and it picks up the correct VI as there is only 1 option. Basically if situation 2 is not intended to work then the way you apply "call parent method" doesn't make sense.
Attachements:
For the really keen I have included 2 zip files
One is the "Revert Method labVIEW project" which is of course not working properly because it wants to "call parent method" on operation not operation2
The other zip file is all pictures with a PIN for both "Revert Method" and "Extend Method" so you can see the subtle but important differences and pictrures of the relavant block diagrams including what NI suggested to me as the original fix for this problem but wasn't (they were suggesting I implement Extend Method).
If you are wondering where I got the names, concepts and PIN diagrams from see:
Elemental Design Patterns
By: Jason McColm Smith
Publisher: Addison-Wesley Professional
Pub. Date: March 28, 2012
Print ISBN-10: 0-321-71192-0
Print ISBN-13: 978-0-321-71192-2
Web ISBN-10: 0-321-71255-2
Web ISBN-13: 978-0-321-71255-4
All the best
David
Attachments:
Call parent node fault.zip ‏356 KB
Call parent node fault.zip ‏356 KB

Hi tst,
Thankyou for your reply. Can you have a look at my comments below on the points you make.
1) Have to disagree on that one. The help is unfortunately not clear. The part you quote in your reply only indicates that the VI you are applying "Call Parent Node" to must be dynamic dispatch. There is nowhere in the help it actually states that the call parent node applies to the VI of the block diagram it is placed into. Basically case 2 in my example fulfills all that the help file requires of it. The dynamic dispatch VI's operation are part of a class that inherits from a given ancestor. Operation 2 for Reverted behaviour is a child VI that is dynamic dispatch and has the same name as the ancestor VI (operation2). The help is missing one important piece of information and should be corrected.
2) True it does work this way. I was trying to build case 2 and had not yet built my ancestor DD for operation so the function dropped but wasn't associated with any VI. I was able to do this via a replace (obviously once the ancestor Vi was built) so this one is just bad operator
3) Keep in mind this is an example not my end goal. I have a child implementation because this is a case where I am trying to do a "reverse override" if you like.
3a) The point of the example is to override an objects method (operation2) with it's parent's method NOT it's own. The reason there is a child implementation with specific code is to prove that the parent method is called not the one that relates to the object (child's VI). If I start having to put case structures into the child VI I make the child VI have to determine which code to execute. The point of Revert method is to take this function out of the method that is doing the work. (Single Use Principal and encapsulation)
3b) The VI I am calling is a Dynamic Dispatch VI. That means if I drop the superclass's VI onto the child's block diagram it will become the child's implementation. Basically I can't use Dynamic Dispatch in this case at all. It would have to be static. That then means I have to put in additional logic unless there is some way to force a VI to use a particular version of a DD VI (which I can't seem to find).
Additional Background
One of the uses for "Revert Method" is in versioning.
I have a parent Version1 implementation of something and a child Version2. The child uses Version2 BUT if it fails the error trapping performs a call to Version1.
LabVIEW has the possibility of handling the scenario but only if both Case 1 and Case 2 work. It would actually be more useful if all 3 cases worked.
The advantage of the call parent method moving one up the tree means I don't have the track what my current object is and choose from a possible list, if, for example the hierarchy is maybe 5 levels deep. (so V4 calls V3 with a simple application of "call parent method" rather than doing additional plumbing with case structures that require care and feeding). Basically the sort of thing OOP is meant to help reduce. Anything that doesn't allow case 2 or 3 means you have to work around the limitation from a software design perspective.
If at the end of the day Case 2 and case 3 don't and won't ever work then the help file entry needs to be fixed.
All the best
David

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Christiaan

Hi,
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Hello, I'm trying to write a program that will call a method from a super class. This program is the test program, so should i include extends in the class declaration? Also, what code is needed for the call? Just to make things clear the program includes three different types of object classes and one abstract superclass and the test program which is what im having problems with. I try to use the test program to calculate somthing for each of them using the abstract method in the superclass, but its overridden for each of the three object classes. Now to call this function what syntax should I include? the function returns a double. Thanks.

Well, this sort of depends on how the methods are overridden.
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        } catch (CreateException ex) {
            System.out.println("Error: " + ex);
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws
            ServletException, IOException {
     * Does insertion of the new user in the database.
    public void doInsert(HttpServletRequest req, HttpServletResponse resp) throws
            ServletException, IOException {
        try {
            // Get parameters to create the newUser
            String login = req.getParameter("login");
            String password = req.getParameter("password");
           // Create the newUser
            System.out.println("Calling newUser before");
            UserRemote user = userSession.newUser(login, password);
            System.out.println("Calling newUser after");
        } catch (Exception e) {
    // Clean up resources
    public void destroy() {
Result :
When I run my jsp page and click on the "add" button, I got the message "Calling newUser before" printed in STDOUT and the error message :
ERROR [[userservlet]] Servlet.service() for servlet userservlet threw exception
javax.servlet.ServletException: loader constraints violated when linking javax/ejb/Handle class
     at noumea.user.UserServlet.service(UserServlet.java:112)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:810)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
     at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:81)
     at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
     at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
     at org.jboss.web.tomcat.security.CustomPrincipalValve.invoke(CustomPrincipalValve.java:39)
     at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:153)
     at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:59)
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
     at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
     at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
     at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856)
     at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744)
     at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
     at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112)
     at java.lang.Thread.run(Thread.java:534)
Constat :
I checked into my SGBD and the new user has been created.
The error appears only when the method return Remote ejbs, if I return simples objects (Strings, int..) it works.
What can I do to resolve this problem ?
Thank you.

"Why do you want to servlet to gain access to another EJB through the stateless session bean. Why cant the servlet call it directly ?"
Because I want to access to the informations included in the entity bean UserBean (which is remote).
You said that it is a bad design, but how can I access to my UserBean ejbs from the session bean if I don't do that ?
For example I want a List of all users to be seen in a jsp page :
1 - I call the method getUserList which returnsan ArrayList of UserRemote.
2 - I iterate over the ArrayList to get the users parameters to be seen.
As the other example (newUser), when I do
ArrayList users = (ArrayList) userSession.getUserList(); with the simple client it works, but in the servlet I got the same error.
But, if I call directly the findAll method (as you'are saying) in the servlet
ArrayList users = (ArrayList) userRemoteHome.findAll(); it works...
I think that if my servlet calls directly entity ejbs, I don't need UserSession bean anymore. Is that right ?
I precise that my design is this :
jsp -> servlet -> session bean -> entity bean -> sgbd
Is that a bad design ? Do I need the session bean anymore ?
Thank you.

Calling a method from another servlet? very beginner

I am going to try to explain what I want to do so just be patient please.
I want to call a method in a seperate servlet to connect and release my connection pool - How do I do this?
This is what I have been trying... help
dbPOOL.class
package DATABASE;
import javax.naming.*;
import javax.sql.*;
import java.sql.*;
import java.util.*;
public class dbPOOL {
Connection con;
private boolean conFree = true;
private String dbName = "java:comp/env/jdbc/connectDB";
public dbPOOL() throws Exception {
     try {
              InitialContext ic = new InitialContext();
              DataSource ds = (DataSource) ic.lookup(dbName);
              con = ds.getConnection();
     } catch (Exception ex) { throw new Exception("Couldn't open connection to database: " + ex.getMessage());
public void remove () {
         try {
             con.close();
        } catch (SQLException ex) { System.out.println(ex.getMessage());}
protected synchronized Connection getConnection() {
         while (conFree == false) {
                 try {
                         wait();
                 } catch (InterruptedException e) {
              conFree = false;
              notify();
              return con;
    protected synchronized void releaseConnection() {
        while (conFree == true) {
                 try {
                    wait();
                 } catch (InterruptedException e) {
              conFree = true;
              notify();
}and my worker servlet connTest
package DATABASE;
import javax.naming.*;
import javax.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.sql.*;
import java.util.*;
public class connTest extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, SQLException, IOException {
         try {
                String selectStatement = "select * " + "from mt.Evendale_Web_Groups";
                getConnection();
                PreparedStatement prepStmt = con.prepareStatement(selectStatement);
                ResultSet rs = prepStmt.executeQuery();
                while (rs.next()) {
                   groupList gl = new groupList(rs.getString(1), rs.getString(2), rs.getString(3));
                prepStmt.close();
        } catch (SQLException ex) { throw Exception(ex.getMessage());}
            releaseConnection();
}When I try to compile the connTest servlet - I keep getting cannot find symbols errors on the methods. How do I fix this?

Which errors exactly?
Try something like this:
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
dbPOOL db = null;
try {
String selectStatement = "select * " + "from mt.Evendale_Web_Groups";
db = new dbPOOL();
Connection con = db.getConnection();
PreparedStatement prepStmt = con.prepareStatement(selectStatement);
ResultSet rs = prepStmt.executeQuery();
while (rs.next()) {
   // process your rs
prepStmt.close();
} catch (Exception ex) {
} finally {
    if (db != null)
         db.releaseConnection();
}Simply change the package name to something else. But don't forget to import your dbPOOL class since it is now located in a diff package. Also be aware of coding standards when naming your classes and packages.

Calling a method from a UICommand Object

How do I call an action method from a UICommand object?
I create a HtmlCommandLink in my backing bean, and I think I should be setting the action, but with what? The method takes a MethodBinding but I can't find much detail on how to get that. I just want to call a method like linkAction1_action() in the example below, but you cannot pass a method.
public class Page1 extends AbstractPageBean {
private HtmlPanelGroup panel = new HtmlPanelGroup();
public HtmlPanelGroup getPanel() {
    return panel;
public void setPanel(HtmlPanelGroup panel) {
    this.panel = panel;
public Page1() {
    HtmlCommandLink link = new HtmlCommandLink();
    link.setAction(/* what do I put here */);
    this.panel.getChildren().add(link);
public String linkAction1_action() {
    return "GoBack";
}

OK. A couple days later and I am able to answer my
own question. Anyway, I will lay it out there for
anyone interested. This worked for me...
public class Page1 extends AbstractPageBean {
private HtmlPanelGroup panel = new HtmlPanelGroup();
public HtmlPanelGroup getPanel() {
return panel;
public void setPanel(HtmlPanelGroup panel) {
this.panel = panel;
public Page1() {
HtmlCommandLink link = new HtmlCommandLink();
link.setAction(
FacesContext.getCurrentInstance()
.getApplication()
.createMethodBinding("#{Page1.linkAction1_action}",
new Class[0]));
this.panel.getChildren().add(link);
public String linkAction1_action() {
return "GoBack";
Since you're setting the action from within the Page1 object, why don't you create a method binding manually? This will be much more performant that using the application to create and EL-based binding.
Try:
link.setAction(new MethodBinding()
      public Object invoke(FacesContext facesContext, Object[] objects) throws EvaluationException, MethodNotFoundException
        return linkAction1_action();
      public Class getType(FacesContext facesContext) throws MethodNotFoundException
        return String.class;
});Note that you also avoid any naming convention - you do not require your Page1 object to be configured as a managed bean "Page1".

What calls getTableCellRendererComponent() method????

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