Which Package to Import to Use FacesContext's getRequestMap()?

[Daniel Gee]

I am trying to use the FacesContext's getRequestMap() method. The compiler cannot recognize the getRequestMap() method.

I think that I have import a certain package in the begining of my Java class to resolve the problem. I have tried a number of packages and they did not work. Does anybody know the answer? Thank you.

[seb petterson]

 import javax.faces.context.FacesContext; 
 
...
 
FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap();

[ August 30, 2005: Message edited by: seb petterson ]

[Daniel Gee]

Thanks for your reply. I think my question boils down to "how to get the Java bean for a particular row in a JSF dataTable. My code is like:

PersonnelBean personnelBean = (PersonnelBean)
            FacesContext.getCurrentInstance().getRequestMap().get("PersonnelBean");

The error message is that "getRequestMap is undefined for the FacesContext". Apparently, the getRequestMap() is not the correct method. Which one is the correct method? Thanks.

[seb petterson]

Originally posted by Daniel Gee:
... the getRequestMap() is not the correct method. Which one is the correct method? Thanks.

See my previous post

[Daniel Gee]

I went to read about what getRequestParameterMap() does. It does not seem to do what I intend to achieve (I can be terribly wrong.)

I intend to get the JavaBean that represents the current row I am hitting in a JSF dataTable.

[Kevin Galligan]

For what you are trying to do, getRequestParameterMap is not the correct function.

What is? It depends on your context. I'll assume you are running this from an action method on a bean? For example...

<h :mrgreen: ataTable value="#{myBean.someTableData}"....
 
</h :mrgreen: ataTable>
<h:commandButton action="#{myBean.someAction}"/>

The java code...

public class MyBean
{
    DataModel someTableData;
    public DataModel getSomeTableData()
    {
        //Get your data
    }
 
    public void setSomeTableData(DataModel asdf){//stuff}
   
    public String someAction()
    {
        //Get current row [B]This is what you're trying to do[/B]
        PersonnelBean personnelBean = (PersonnelBean)someTableData.getRowData();
 
        //.... Whatever you need to do
        return "somestring";
    }
 
}
 

I think you could also write your action method on your PersonnelBean and work from there if you were linking in your table, but I'll leave that for somebody else. I think you're safely out of the request map function area.

BTW, I'm fairly new, so somebody please step in and clomp all over this if its inaccurate.

[Daniel Gee]

Maybe I should post my code for people to understand what I am really trying to do. I have a dataTable. For each row in that table, there is a checkbox. My backing bean will select the row or rows for which the checkbox is/are marked by an user.

The syntax error occurred at which I try to get the JavaBean of the "checked" row. E.g.

MailBean mailBean = (MailBean)
          FacesContext.getCurrentInstance().getRequestMap().get("mailBean");

Here is the JSF showing in the browser:

<h:form id="mailbox">
  <h :mrgreen: ata_table value="#{mailsForm.mails}" var="mailBean" binding="#{mybean.table}">
    <h:column>
        <f:facet>
            <h :-o	 utput_text value="Selected"/>
        </f:facet>
        <h:selectboolean_checkbox id="selected" binding="#{mybean.selected}"/>
    </h:column>
    <h:column>
        <f:facet>
            <h :-o	 utput_text value="From"/>
        </f:facet>
        <h :-o	 utput_text id="from" value="#{mailBean.from}"/>
    </h:column>
    ...
  </h :mrgreen: ata_table>
  <h:command_button id="delete" action="#{mybean.delete}"/>
</h:form>
 
Here is the code for the backing bean:
 
  public class MyBean {
 
    // Property bound to the "selected" checkbox
    UISelectBoolean selected;
    public UISelectBoolean getSelected() {
      return selected;
    }
    public void setSelected(UISelectBoolean selected) {
      this.selected = selected;
    }
 
    // Property bound to the entire table
    UIData table;
    public UIData getTable() {
      return table;
    }
    public void setTable(UIData table) {
      this.table = table;
    }
 
    // Method to delete all the selected messages
    public String delete() {
 
        // Iterate through the data rows ...
        int first = table.getFirst();
        int rows = table.getRows();
        for (int index = first; index < (first + rows); index++) {
 
            // Position the table at the current row ...
            table.setRowIndex(index);
 
            // And get the message bean for this row ...
           MailBean mailBean = (MailBean)
             FacesContext.getCurrentInstance().getRequestMap().get("mailBean");
 
            // If this row is selected, delete the corresponding message
            if (selected.isSelected()) {
                ...
            }
 
        }
        table.setRowIndex(-1); // We're done now
        return (null); // Redisplay the current page
 
    }
 

[Daniel Gee]

OKay, the problem has been resolved. I am missing getExternalContext() in the chain.

[Kevin Galligan]

Does that code work? I don't see how it would.

MailBean mailBean = (MailBean)FacesContext.getCurrentInstance().getRequestMap().get("mailBean");

Unless I'm way off, this will always return the same thing in your loop, and I highly doubt it'll be an instance of 'MailBean'. The request map is the collection of request parameters from the browser. Yes?

I think something like the following would work better:

 
// Method to delete all the selected messages
    public String delete() {
 
    DataModel mailData = getMailsForm().getMails();
    List mails = (List)mailData.getWrappedData();
 
        // Iterate through the data rows ...
        // This is for pagination?  Not sure how to do this.
        int first = 0;
        int rows = mails.size();
        for (int index = first; index < (first + rows); index++) {
 
            MailBean mailBean = (MailBean)mails.get(index);
 
            // If this row is selected, delete the corresponding message
            if (mailBean.isSelected()){
                ...
            }
 
        }
        
        return "redisplay"; //Or null, I guess
    }
 

The checkbox code would have to look like...

<h:selectboolean_checkbox id="selected" binding="#{mailBean.selected}"/>

I guess that's it. Were I implementing this, I don't think I'd try to use the binding and interface objects. Let JSF set the values on your MailBean objects directly and just use them.

[Kevin Galligan]

Sorry, I think it would be...

<h:selectboolean_checkbox id="selected" value="#{mailBean.selected}"/>

[Daniel Gee]

What I mean is I should change the code to:

           MailBean mailBean = (MailBean)             FacesContext.getCurrentInstance().getExternalContext().getRequestMap().get("mailBean"); 

note that I missed the getExternalContext() in my previous posting. What do you think?

[Kevin Galligan]

Oh, I know what you meant. I'm saying that I don't see how that would work. The experts will have to correct me if I'm off, but

FacesContext.getCurrentInstance().getExternalContext().getRequestMap().get("mailBean");

is essentially the same as...

request.getAttribute("mailBean")

Who's putting the value into the attribute? 'table.setRowIndex(index);'? That is beyond my understanding of JSF, but I'd bet that doesn't work. If it does, I still think its far more complex and strange than it needs to be.

[JiaPei Jen]

Hi, thanks for your reply. I am trying to get all the data from the submitted table.

What is the type of

MailsForm.getMails(); ?

Because "mails" is a List.

I am having difficult time with "type casting" in this statement:

DataModel mailData = MailsForm.getMails();

List is not consistent with DataModel. and the next statement:

List mails = (List)mailData.getWrappedData();

[Kevin Galligan]

DataModel is the wrapper for table data is JSF. If you get a chance, read up on it. In situations where you need to select a particular row, for example, DataModel comes in handy.

In your case you can pretty easliy use List directly...

public String delete() {
 
    [B]List mails = getMailsForm().getMails();[/B]
    
        // Iterate through the data rows ...
        // This is for pagination?  Not sure how to do this.
        int first = 0;
        int rows = mails.size();
        for (int index = first; index < (first + rows); index++) {
 
            MailBean mailBean = (MailBean)mails.get(index);
 
            // If this row is selected, delete the corresponding message
            if (mailBean.isSelected()){
                ...
            }
 
        }
        
        return "redisplay"; //Or null, I guess
    }

[Kevin Galligan]

Now, looking at your last post, I have another concern:

DataModel mailData = MailsForm.getMails();

Is 'getMails' a static method on the MailsForm class? That's trouble. You won't have any problem while developing because you won't have more than 1 user. With multiple users you'll have problems.

[JiaPei Jen]

Huh? Sorry, I am lost. In fact, I never understand

getMailsForm().getMails(); 

The managed-bean-class that feed the data to my original <h ataTable ..> is MailsForm.java and "mails" is the List that contains all the data to populate all the rows and columns of that table. I use mailsForm as the managed-bean-name. Maybe, I should show you the managed-bean-class to make sure that we are using the same terms:

public class MailsForm 
{
    private List mails = new ArrayList();

    public MailsForm()
    {
   
// instantiate the business delegate
ListMails listMails = new ListMails();
mails = listMails.getMailsInfo();
 
    }
 
/**
 * @return Returns the mails.
 */
public List getMails() {
return mails;
}
/**
 * @param mails The mails to set.
 */
public void setPersonnel(List mails) {
this.mails = mails;
}
}// End MailsForm.java
 

Therefore, when I display my original table, I coded:

<h:form id="mailbox">
  <h :mrgreen: ata_table value="#{mailsForm.mails}" var="xxx">

Now, the above table is submitted for processing. I am trying to retrieve all the selected records from that submitted table. I cannot compile code with the code below:

getMailsForm().getMails();  // give me syntax error

Another question is that "selected" is a boolean property on my MailBean that can be used to mark which messages have been selected. Therefore, to test whether the message gets selected, I should code:

get an instance of the MailBean and name it mailBean, and then

if ( mailBean.selected ) { .... }

instead of

if ( selected.isSelected() ) { ... }

What are the mistakes that I have made. I really want to learn from this exercise.

[Kevin Galligan]

I think you'll have to repost your code. I'm getting lost.

I looked up at your jsp code, and you need to set the value property on your checkbox rather than your binding property. Also, where are you putting your 'delete' method. It would make more sense on the mailsForm than the 'mybean' where I had put it.

Anyway, please post the code in more detail.

[JiaPei Jen]

Thanks for your attention and help first. In fact, the MailsForm and mails are the names I made up for asking questions on this forum. I am working on "personnel".

managed-bean-class: ListAction and managed-bean-name: listAction

package processAction;
 
import java.util.List;
import java.util.ArrayList;
import processDelegate.ListPersonnel;
 
public class ListAction 
{
    private List personnel = new ArrayList();

    public ListAction()
    {
   
// instantiate the business delegate
ListPersonnel listPersonnel = new ListPersonnel();
personnel = listPersonnel.getPersonnelInfo();
 
    }
public List getPersonnel() {
return personnel;
}
public void setPersonnel(List personnel) {
this.personnel = personnel;
}
}// End ListAction.java

I manually typed in some data in the ListPersonnel.java class. Eventually, I am going to get real data from receiving an iBatis object.

package processDelegate;
 
import java.util.List;
import java.util.ArrayList;
 
public class ListPersonnel {

private String [] ssnList = {"123-45-6789", "987-65-4321", "234-56-7891", "198-76-5432"};
    private String [] oplanList = {"DCAPES", "DSIS", "CMMS", "GCCS"};
    private String [] nameList = {"John Doe", "Jane Doe", "Edward Smith", "June Harris"};
 
    List personnel = new ArrayList();
    
    public List getPersonnelInfo()
    {
    for ( int i=0; i<4; i++)
    {
    PersonnelBean pb = new PersonnelBean();
 
    pb.ssn = ssnList[ i ];
    pb.oplan = oplanList[ i ];
    pb.name = nameList[ i ];
    personnel.add( pb );
    }
    return personnel;
    }
}

and the PersonnelBean.java looks like:

package processDelegate;
 
/**
 * @author cjen
 *
 * TODO To change the template for this generated type comment go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
 
public class PersonnelBean 
{
 
    boolean selected;
    String ssn;
    String oplan;
    String name;
 
    public boolean getSelected() 
    {
      return selected;
    }
    public void setSelected(boolean selected) 
    {
      this.selected = selected;
    }

    public PersonnelBean()
    {
    //Empty Constructor
    }
 
    public String getSsn() 
    { 
        return ssn; 
    }     
    
    public void setSsn( String data ) 
    { 
        this.ssn = data; 
    } 
    
    public String getOplan() 
    { 
        return oplan; 
    } 
 
    public void setOplan( String data ) 
    { 
        this.oplan = data; 
    }
    
    public String getName() 
    { 
        return name; 
    } 
 
    public void setName( String data ) 
    { 
        this.name = data; 
    }
 
}

and my JSF dataTable gets created:

<f:view>
            <h:form id="selectPersonnel">
            <h :mrgreen: ataTable style="width: 220px; height: 200px; overflow: auto;" value="#{listAction.personnel}" var="pInfo" >
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
    <f:facet name="header">
               <h :-o	 utputText value="Selected"/>
        </f:facet>
        <h:selectBooleanCheckbox id="selected" />
   </h:column>
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
            <h :-o	 utputText value="SSN"/>
        </f:facet>    
        <h :-o	 utputText id="ssn" value="#{pInfo.ssn}"/>
    </h:column>
    <h:column>
        <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
            <h :-o	 utputText value="OPLAN"/>
        </f:facet>
        <h :-o	 utputText id="oplan" value="#{pInfo.oplan}"/>
    </h:column>
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
            <h :-o	 utputText value="Name"/>
        </f:facet>
        <h :-o	 utputText id="name" value="#{pInfo.name}"/>
    </h:column>
  </h :mrgreen: ataTable>
  <p>
  <h:commandButton id="Depart" value="DEPART" action="SelectAction.updateDeparturePersonnel"/>
</h:form>
</f:view>

the action="SelectAction.updateDeparturePersonnel" will invoke the class shown below. And this is the class I have problems with:

Problem 1. Retrieve all submitted data in the table displayed above
Problem 2. The "testing" of whether checkbox of each row of the table is selected or not is not working properly.

package processAction;
 
import java.util.List;
import java.util.ArrayList;
import javax.faces.model.ListDataModel;
import javax.faces.context.FacesContext;
 
import processDelegate.PersonnelBean;
import processDelegate.SelectPersonnel;
 
public class SelectAction 
{
private List personnel = new ArrayList();
private List departurePersonnel = new ArrayList();
private ListDataModel ldm = null;

public SelectAction()
{
ldm = new ListDataModel(  personnel );
}

public List updateDeparturePersonnel( ) 
{
    List personnel = (List)ldm.getWrappedData();
    
        // Iterate through the data rows ...
        int first = 0;
        int rows = personnel.size();
        for (int index = first; index < (first + rows); index++) 
        {
        PersonnelBean personnelBean = ( PersonnelBean )personnel.get(index);
 
            // If this row is selected, add all data fields the corresponding personnel
            if ( personnelBean.selected )
            {
                departurePersonnel.add( personnelBean );
            }
        }
        return departurePersonnel;
}

    public List getDeparturePersonnel() 
    {
      return departurePersonnel;
    }
    public void setDeparturePersonnel( List departurePersonnel ) 
    {
      this.departurePersonnel = departurePersonnel;
    }
 
}

And I have to use the List "departurePersonnel" to display another <h ataTable ...> in the browser.

Sorry for the pain that inflicts on you.

[Kevin Galligan]

Ok. Now I see. Please don't take offense, but I think you should revisit some JSF concepts. You are going to be a little lost until you get that sorted out (I was in the same boat a couple weeks ago). However, I think I can get this cleared up. At least "working" and you'll have to fill it out from there.

In general, I think you're in Struts mode. You have 2 separate 'Action' classes. What you really need is one bean class for this operation. I've kind of merged the 2 and created 'PeopleManagementBean'.

Also, the action method was returning a List. To who? The signiture of action methods is no arg and returns a String.

Anyway...

*** PeopleManagementBean ***

public class PeopleManagementBean 
{
    private List personnel = new ArrayList();

    public PeopleManagementBean()
    {
   
// instantiate the business delegate
ListPersonnel listPersonnel = new ListPersonnel();
personnel = listPersonnel.getPersonnelInfo();
 
    }
public List getPersonnel() {
return personnel;
}
public void setPersonnel(List personnel) {
this.personnel = personnel;
}

public [B]String[/B] updateDeparturePersonnel( ) 
{
    List departurePersonnel = new ArrayList();
    
        // Iterate through the data rows ...
        for (int index=0; index<personnel.size(); index++) 
        {
        PersonnelBean personnelBean = ( PersonnelBean )personnel.get(index);
 
            // If this row is selected, add all data fields the corresponding personnel
            if ( personnelBean.selected )
            {
            departurePersonnel.add( personnelBean );
            }
        }
        
        [B]//Who were you returning this List to?
        //return departurePersonnel;[/B]
        
        //Do something system-like with your departurePersonnel data
        
        return "success";
}

}// End PeopleManagementBean.java

As for the front end, that was a little closer to the mark. The important difference is the change I made to the checkbox. Also, your commandButton didn't have the #{} stuff, so it wouldn't have executed anything. I also changed that to point to listAction.

<f:view>
    <h:form>
        <h :mrgreen: ataTable style="width: 220px; height: 200px; overflow: auto;" value="#{peopleManagementBean.personnel}" var="pInfo">
<h:column>
<f:verbatim ><div style="white-space: nowrap"></f:verbatim>
<f:facet name="header">
       <h :-o	 utputText value="Selected"/>
</f:facet>
[B]<h:selectBooleanCheckbox value="#{pInfo.selected}"/>[/B]
</h:column>
<h:column>
<f:verbatim ><div style="white-space: nowrap"></f:verbatim>
<f:facet name="header">
    <h  utputText value="SSN"/>
</f:facet>    
<h :-o	 utputText id="ssn" value="#{pInfo.ssn}"/>
    </h:column>
<h:column>
<f:verbatim ><div style="white-space: nowrap"></f:verbatim>
<f:facet name="header">
    <h  utputText value="OPLAN"/>
</f:facet>
<h :-o	 utputText id="oplan" value="#{pInfo.oplan}"/>
    </h:column>
    <h:column>
<f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
    <h :-o	 utputText value="Name"/>
</f:facet>
<h :-o	 utputText id="name" value="#{pInfo.name}"/>
    </h:column>
  </h  ataTable>
  <p>
  [B]<h:commandButton id="Depart" value="DEPART" action="#{peopleManagementBean.updateDeparturePersonnel}"/>[/B]
</h:form>
</f:view>

The important concept here is that the updates you make in the table (to the checkboxes) will be pushed directly to your PersonnelBean objects in the list 'peopleManagementBean.personnel'. Just go directly to that and use it.

I didn't do anything with the 'departurePersonnel' List. You'll have to deal with that in the class. It just builds the list and leaves it there.

Hope this clears things up.

[Daniel Gee]

You are right. I did a couple of web applications using the Struts. Presently, I am working on two applications; one uses the Struts framework and I am learning JSF to code the other application.

I am not offended. I simply read a JSF book for about a week. I certainly have a lot to learn.

The front end xxx.jsp (coded in JSF) will navigate to yyy.jsp after the

action="#{peopleManagementBean.updateDeparturePersonnel}"

is invoked. The yyy.jsp will use the List departurePersonnel to display another table in the browser window. That is to say,

<h:dataTable value="#{peopleManagementBean.departurePersonnel}" >

I still have problems with

<h:selectBooleanCheckbox value="#{pInfo.selected}"/>

I declare �selected� as primitive boolean in my PersonnelBean and have a pair of get and set methods for that property. I typed and fed some data to populate the PersonnelBean:

    private String [] ssnList = {"123-45-6789", "987-65-4321", "234-56-7891", "198-76-5432"};
    private String [] oplanList = {"DCAPES", "DSIS", "CMMS", "GCCS"};
    private String [] nameList = {"John Doe", "Jane Doe", "Edward Smith", "June Harris"};

The compiler complains about the

value=�#{pInfo.selected}�

in the <h:selectBooleanCheckbox �> tag and the

 if ( personnelBean.selected ) { � } 

in the PeopleManagementBean class.

I am on the east coast of the U.S. It is 8:40 pm now. I am going to test the code some more tomorrow morning.

In the "detailed" code that you saw, I put a "selected" boolean property on my "Personnel" bean that can be used to mark which persons have been selected for departure.

I initially did not have a boolean "selected" property on the "Personnel" bean. At that time, I tried to bind components into the backing bean. Therefore, I posted a question regarding

PersonnelBean personnelBean = (PersonnelBean)             FacesContext.getCurrentInstance().getExternalContext().getRequestMap().get("personnelBean");

Sorry for the confusion that I caused.

[Kevin Galligan]

I'm guessing you need to add 'isSelected' instead of 'getSelected' for a primitive boolean.

I was thinking of changing that reference...

if ( personnelBean.selected ) { � }

but I figured I'd change as little as possible. You should call your accessor method, or change 'boolean selected;' in PersonnelBean to be public (hint: use the accessor method).

[Daniel Gee]

The "checkbox" problem is resolved. I would like to post the code for others to know how to do it. Like you said, "isSelectedPersonnel" should be used instead the "getSelectedPersonnel". Please note the specification in bold.

boolean selectedPersonnel;
 public boolean isSelectedPersonnel()
 {
return selectedPersonnel;
}
 public void setSelectedPersonnel( boolean selectedPersonnel )
 {
this.selectedPersonnel = selectedPersonnel;
}

Then in the xxx.jsp coded in JSF, we must add an attribute 'onClick' in the h:selectBooleanCheckbox tag; otherwise, the compiler does not like it:

I still have problem with the method "updateDeparturePersonnel()". The action button of the xxx.jsp

action="#{departure.updateDeparturePersonnel}"

where departure is the name of the managed bean in my configuration file:

 <managed-bean>
  <managed-bean-name>arrival</managed-bean-name>
  <managed-bean-class>processAction.DepartureManagementBean</managed-bean-class>
  <managed-bean-scope>session</managed-bean-scope>
 </managed-bean>
 <managed-bean>
  <managed-bean-name>departure</managed-bean-name>
  <managed-bean-class>processAction.DepartureManagementBean</managed-bean-class>
  <managed-bean-scope>session</managed-bean-scope>
 </managed-bean>

took me to that method; i.e. updateDeparturePersonnel();
However, I got run-time ClassCastException when hitting the updateDeparturePersonnel(); method in the DepartureManagementBean.java. And I am unable to see the coding problems.

java.lang.ClassCastException
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:72)
javax.faces.component.UICommand.broadcast(UICommand.java:312)
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:267)
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:381)
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:75)
com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:200)
com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:90)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:197)

Here is my DepartureManagementBean.java:

package processAction;
 
import java.util.ArrayList;
import java.util.List;
 
import processDelegate.ListPersonnel;
import processDelegate.PersonnelBean;
 
public class DepartureManagementBean 
{
    private List personnel = new ArrayList();
    private List departurePersonnel = new ArrayList();
    
    // The constructor and the creation of the List "personnel" has been successfully tested
    public DepartureManagementBean()
    {
   
// instantiate the business delegate
ListPersonnel listPersonnel = new ListPersonnel();
personnel = listPersonnel.getPersonnelInfo();
 
    }
 
public List getPersonnel() 
{
return personnel;
}
public void setPersonnel( List personnel ) 
{
this.personnel = personnel;
}
 
public List updateDeparturePersonnel( ) 
{
        // Iterate through the data rows ...
        for ( int index = 0; index < personnel.size(); index++ ) 
        {
            PersonnelBean personnelBean = new PersonnelBean();
        personnelBean = ( PersonnelBean )personnel.get(index);
 
            // If this row is selected, add all data fields the corresponding message
            if ( personnelBean.isSelectedPersonnel() )
            {
                departurePersonnel.add( personnelBean );
            }
        }
        return departurePersonnel;
}

    public List getDeparturePersonnel() 
    {
      return departurePersonnel;
    }
    public void setDeparturePersonnel( List departurePersonnel ) 
    {
      this.departurePersonnel = departurePersonnel;
    }

}// End DepartureManagementBean.java

[Kevin Galligan]

Your updateDeparturePersonnel method is returning a List. I needs to return a String. The string is used for the navigation...

http://java.sun.com/j2ee/1.4/docs/tutorial/doc/JSFIntro5.html#wp116912

See the last paragraph of that section. It starts with...

"The outcome can also come from the return value of an action method in a backing bean."

That's what you're doing. You need to return a string from your method. If you need access to your List, its in your managed bean which is in the session, so just grab it from somewhere else.

The ClassCastException is probably coming from JSF trying to cast your List to a String.

Now, just a question. I'm not sure it "matters", but why 2 managed beans of the same type?

[Daniel Gee]

I have made revisions of the DepartureManagementBean.java accordingly. The ClassCastException problem is gone. But, another runtime error occurred.

The action button of the first web page (successfully displayed) is

action="#{DepartureManagementBean.updateDeparturePersonnel}"

I clicked on the button, the runtime error is MethodNotFoundException:

javax.faces.FacesException: #{DepartureManagementBean.updateDeparturePersonnel}: javax.faces.el.MethodNotFoundException: updateDeparturePersonnel
com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:74)
javax.faces.component.UICommand.broadcast(UICommand.java:312)
javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:267)
javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:381)
com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:75)
com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:200)
com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:90)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:197)

Here is the up-to-date code:

package processAction;
 
import java.util.ArrayList;
import java.util.List;
import processDelegate.ListPersonnel;
import processDelegate.PersonnelBean;
 
public class DepartureManagementBean 
{
private List personnel = new ArrayList();
    private List departurePersonnel = new ArrayList();
    
    public DepartureManagementBean()
    {
   
    // instantiate the business delegate
    ListPersonnel listPersonnel = new ListPersonnel();
    personnel = listPersonnel.getPersonnelInfo();
 
    }
 
public List getPersonnel() 
{
return personnel;
}
 
public void setPersonnel( List personnel ) 
{
this.personnel = personnel;
}
 
public String updateDeparturePersonnel( ) 
{
        // iterate through the data rows ...
        for ( int index = 0; index < personnel.size(); index++ ) 
        {
        PersonnelBean personnelBean = ( PersonnelBean )personnel.get( index );
 
            // If this row is selected, add all data fields the corresponding message
            if ( personnelBean.isSelectedPersonnel() )
            {
                departurePersonnel.add( personnelBean );
            }
        }
        return "sucess";
}

    public List getDeparturePersonnel() 
    {
      return departurePersonnel;
    }
    public void setDeparturePersonnel( List departurePersonnel ) 
    {
      this.departurePersonnel = departurePersonnel;
    }

}// End DepartureManagementBean.java

[Kevin Galligan]

Right now your action param is...

action="#{DepartureManagementBean.updateDeparturePersonnel}"

Assuming your managed bean declarations are the same as before your action param should be...

action="#{departure.updateDeparturePersonnel}"

[Daniel Gee]

I have tried

action="#{departure.updateDeparturePersonnel}"

and when I click on the DEPART button, nothing happens. I do not even see an error message. The first web page remains on the screen.

I have also tried

action="#{arrival.updateDeparturePersonnel}"

Again, nothing happens when I click on the DEPART button. No response at all.

You are right. In fact, I do not need two "managed-bean-name, managed-bean-class" specification in the faces-config.xml file. I also tried only one specification. The same thing happens - no response.

action="#{DepartureManagementBean.updateDeparturePersonnel}"

at least gives MethodNotFoundException.

It does not hurt to try again. But, the outcome may be the same.

Sorry for bothering you this much.

[ September 02, 2005: Message edited by: Daniel Gee ]
[ September 02, 2005: Message edited by: Daniel Gee ]

[Kevin Galligan]

Ok. I think this is again where you need to hit the books. You need to return a string from your function. That string needs to match up with a navigation rule 'outcome', which will then forward you to another page.

Lets say your list page is 'departureList.jsp' and you want to return to your home page, 'home.jsp'. In your action method, return "success" if everything works out ok. Add the following to your faces-config.xml.

<navigation-rule>
<from-view-id>/departureList.jsp</from-view-id>
<navigation-case>
<from-outcome>success</from-outcome>
<to-view-id>/home.jsp</to-view-id>
</navigation-case>
</navigation-rule>

If you return a string but you don't have a navigation rule associated, it'll just show the page again.

[Daniel Gee]

I think that I should fix my faces-config.xml file. However, the same story repeated. When I tried

action="#{departure.updateDeparturePersonnel}"
or 
action="#{arrival.updateDeparturePersonnel}"

I have no response. I still see the first web page on the screen after clicking on the DEPART button.

action="#{DepartureManagementBean.updateDeparturePersonnel}"

gives me the MethodNotFoundException.

Here is my up-to-date faces.config.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE faces-config PUBLIC "-//Sun Microsystems, Inc.//DTD JavaServer Faces Config 1.1//EN"
                              "http://java.sun.com/dtd/web-facesconfig_1_1.dtd">
<faces-config>
 <managed-bean>
  <managed-bean-name>arrival</managed-bean-name>
  <managed-bean-class>processAction.DepartureManagementBean</managed-bean-class>
  <managed-bean-scope>session</managed-bean-scope>
 </managed-bean>
 <managed-bean>
  <managed-bean-name>departure</managed-bean-name>
  <managed-bean-class>processAction.DepartureManagementBean</managed-bean-class>
  <managed-bean-scope>session</managed-bean-scope>
 </managed-bean>
 <navigation-rule>
  <from-view-id>/pages/welcome.jsp</from-view-id>
  <navigation-case>
   <from-outcome>list</from-outcome>
   <to-view-id>/pages/arrivedPersonnelList.jsp</to-view-id>
  </navigation-case>
 </navigation-rule>
 <navigation-rule>
  <from-view-id>/pages/arrivedPersonnelList.jsp</from-view-id>
  <navigation-case>
   <from-outcome>success</from-outcome>
   <to-view-id>/pages/departurePersonnelList.jsp</to-view-id>
  </navigation-case>
 </navigation-rule>
 <lifecycle/>
 <application>
  <locale-config/>
 </application>
 <factory/>
</faces-config>

[Kevin Galligan]

The url for the page you're on is '/pages/arrivedPersonnelList.jsp'? If so, returning 'success' from your action method should push you to '/pages/departurePersonnelList.jsp'. This is the correct sequence? It should work, so restart your server, doublecheck everything, etc.

[Daniel Gee]

I have shut down the server and tried a couple of times. I am pulling my hair.

I feel like posing all the code again including the faces-config.xml file.

My first page is welcome.jsp:

<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %>
 
<html>
<f:view>
<head>
<title></title>
</head>
 
<body>
<h:form>
<h3>Depart Military Personnel</h3>
<h:commandButton value="List Military Personnel" action="list"/>
</h:form>
</body>
</f:view>
</html>  

The second page is arrivedPersonnelList.jsp. Note that I am unable to post on this forum by inserting that attribute that toggles the marking of the checkboxs in the code, but that attribute is needed:

<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %> 
 
<html>
<head>
<title>List of Personnel Candidates for Departure</title>
</head>
<body>
<f:view>
            <h:form id="selectPersonnel">
            <h:panelGroup style="width: 220px; height: 200px; overflow: auto;">
            <h:dataTable value="#{arrival.personnel}" var="pInfo" >
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
    <f:facet name="header">
               <h:outputText value="Selected"/>
        </f:facet>
        <h:selectBooleanCheckbox id="select" value="#{pInfo.selectedPersonnel}" />
   </h:column>
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
            <h:outputText value="SSN"/>
        </f:facet>    
        <h:outputText id="ssn" value="#{pInfo.ssn}"/>
    </h:column>
    <h:column>
        <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
            <h:outputText value="OPLAN"/>
        </f:facet>
        <h:outputText id="oplan" value="#{pInfo.oplan}"/>
    </h:column>
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
            <h:outputText value="Name"/>
        </f:facet>
        <h:outputText id="name" value="#{pInfo.name}"/>
    </h:column>
  </h:dataTable>
  </h:panelGroup>
  <p>
  <h:commandButton id="Depart" value="DEPART" action="#{DepartureManagementBean.updateDeparturePersonnel}"/>
</h:form>
</f:view>
</body>
</html>  

Hopefully, I will be able to see the third page soon, which is departurePersonnelList.jsp:

<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %> 
 
<html>
<head>
<title>List of Personnel Candidates for Departure</title>
</head>
<body>
<f:view>
            <h:form id="departurePersonnel">
                <h:panelGroup style="width: 220px; height: 200px; overflow: auto;">
                <h:dataTable value="#{departure.departurePersonnel}" var="dInfo" >
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
    <f:facet name="header">
            <h:outputText value="SSN"/>
        </f:facet>    
        <h:outputText id="ssn" value="#{dInfo.ssn}"/>
    </h:column>
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
    <f:facet name="header">
            <h:outputText value="OPLAN"/>
        </f:facet>
        <h:outputText id="oplan" value="#{dInfo.oplan}"/>
    </h:column>
    <h:column>
    <f:verbatim ><div style="white-space: nowrap"></f:verbatim>
   <f:facet name="header">
            <h:outputText value="Name"/>
        </f:facet>
        <h:outputText id="name" value="#{dInfo.name}"/>
    </h:column>
  </h:dataTable>
  </h:panelGroup>
</h:form>
</f:view>
</body>
</html>  

The management bean is DepartureManagementBean.java in the processAction folder:

package processAction;
 
import java.util.ArrayList;
import java.util.List;
import processDelegate.ListPersonnel;
import processDelegate.PersonnelBean;
 
public class DepartureManagementBean 
{
    private List personnel = new ArrayList();
    private List departurePersonnel = new ArrayList();
    
    public DepartureManagementBean()
    {
   
    // instantiate the business delegate
    ListPersonnel listPersonnel = new ListPersonnel();
    personnel = listPersonnel.getPersonnelInfo();
 
    }
 
public List getPersonnel() 
{
return personnel;
}
public void setPersonnel( List personnel ) 
{
this.personnel = personnel;
}
 
public String updateDeparturePersonnel( ) 
{
        // iterate through the data rows ...
        for ( int index = 0; index < personnel.size(); index++ ) 
        {
        PersonnelBean personnelBean = ( PersonnelBean )personnel.get( index );
 
            // If this row is selected, add all data fields the corresponding message
            if ( personnelBean.isSelectedPersonnel() )
            {
                departurePersonnel.add( personnelBean );
            }
        }
        return "sucess";
}
 
    public List getDeparturePersonnel() 
    {
      return departurePersonnel;
    }
    public void setDeparturePersonnel( List departurePersonnel ) 
    {
      this.departurePersonnel = departurePersonnel;
    }

}// End DepartureManagementBean.java

The files that assist the creation of the List personnel are in the processDelegate folder:

package processDelegate;
 
import java.util.List;
import java.util.ArrayList;
 
public class ListPersonnel {

private String [] ssnList = {"123-45-6789", "987-65-4321", "234-56-7891", "198-76-5432"};
    private String [] oplanList = {"DCAPES", "DSIS", "CMMS", "GCCS"};
    private String [] nameList = {"John Doe", "Jane Doe", "Edward Smith", "June Harris"};
 
    List personnel = new ArrayList();
    
    public List getPersonnelInfo()
    {
    for ( int i=0; i<4; i++)
    {
    PersonnelBean pb = new PersonnelBean();
 
    pb.ssn = ssnList[ i ];
    pb.oplan = oplanList[ i ];
    pb.name = nameList[ i ];
    personnel.add( pb );
    }
    return personnel;
    }
}

and the PersonnelBean.java:

package processDelegate;
 
public class PersonnelBean 
{
 
boolean selectedPersonnel;
        String ssn;
String oplan;
String name;
 
    public PersonnelBean()
    {
    //Empty Constructor
    }
 
public boolean isSelectedPersonnel() 
{
return selectedPersonnel;
}
 
public void setSelectedPersonnel( boolean selectedPersonnel ) 
{
this.selectedPersonnel = selectedPersonnel;
}
    
    public String getSsn() 
    { 
        return ssn; 
    }     
    
    public void setSsn( String data ) 
    { 
        this.ssn = data; 
    } 
    
    public String getOplan() 
    { 
        return oplan; 
    } 
 
    public void setOplan( String data ) 
    { 
        this.oplan = data; 
    }
 
    public String getName() 
    { 
        return name; 
    } 
 
    public void setName( String data ) 
    { 
        this.name = data; 
    }
 
}

and my faces-config.xml file is:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE faces-config PUBLIC "-//Sun Microsystems, Inc.//DTD JavaServer Faces Config 1.1//EN"
                              "http://java.sun.com/dtd/web-facesconfig_1_1.dtd">
<faces-config>
 <managed-bean>
  <managed-bean-name>arrival</managed-bean-name>
  <managed-bean-class>processAction.DepartureManagementBean</managed-bean-class>
  <managed-bean-scope>session</managed-bean-scope>
 </managed-bean>
 <managed-bean>
  <managed-bean-name>departure</managed-bean-name>
  <managed-bean-class>processAction.DepartureManagementBean</managed-bean-class>
  <managed-bean-scope>session</managed-bean-scope>
 </managed-bean>
 <navigation-rule>
  <from-view-id>/pages/welcome.jsp</from-view-id>
  <navigation-case>
   <from-outcome>list</from-outcome>
   <to-view-id>/pages/arrivedPersonnelList.jsp</to-view-id>
  </navigation-case>
 </navigation-rule>
 <navigation-rule>
  <from-view-id>/pages/arrivedPersonnelList.jsp</from-view-id>
  <navigation-case>
   <from-outcome>success</from-outcome>
   <to-view-id>/pages/departurePersonnelList.jsp</to-view-id>
  </navigation-case>
 </navigation-rule>
 <lifecycle/>
 <application>
  <locale-config/>
 </application>
 <factory/>
</faces-config>

The last one is my web.xml file:

<?xml version="1.0"?> 
<!DOCTYPE web-app PUBLIC 
  "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" 
  "http://java.sun.com/dtd/web-app_2_3.dtd"> 
<web-app> 
 
    <context-param>
        <param-name>javax.faces.STATE_SAVING_METHOD</param-name>
        <param-value>server</param-value>
    </context-param>
 
    <context-param>
        <param-name>javax.faces.CONFIG_FILES</param-name>
        <param-value>/WEB-INF/faces-config.xml</param-value>
    </context-param>
 
    <listener>
        <listener-class>com.sun.faces.config.ConfigureListener</listener-class>
    </listener>
 
    <!-- Faces Servlet -->
    <servlet>
        <servlet-name>Faces Servlet</servlet-name>
        <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
        <load-on-startup> 1 </load-on-startup>
    </servlet>
 

    <!-- Faces Servlet Mapping -->
    <servlet-mapping>
        <servlet-name>Faces Servlet</servlet-name>
        <url-pattern>/faces/*</url-pattern>
    </servlet-mapping>
    
</web-app>

[Daniel Gee]

Kevin, my first experiment of JSP has been tested successfully. Thank you for holding my hands to go through it. During the process, I had to adjust some concepts and tune myself to this new technology.

On Friday, I did not know the JSF code actually worked. That afternoon, I shut down and re-started the server many times. The DEPART button did not respond to my clickings at all. I was too frustrated to stay in office. I brought all the JSP, Java Class, and configuration files home.

At home, I simply copied all those files and re-ran the application. No problem!

I found that sometimes I must shut down my PC (shutting down the server only is not enough). Somehow, PC can cache something somewhere and the outdated specifications simply do not go away.

I truly appreciation your help. Thanks a lot again. I could not have completed my first exercise without you.

My complete code is posted. Maybe others who are new to JSF can take a look at the discussions and save some effort.
[ September 05, 2005: Message edited by: Daniel Gee ]