And again bean-data in JSPDynPage

[Former Member]

Hi everybody,

as already read several times, I've got the same problem performing my first steps in EP content programming.

Within the jsp the bean is not present. When I define a non-default constructor for the bean, an exception is thrown, so the jsp tries to create a new instance, because it finds nothing in the session.

But where is my object?

Instead of session.(set|get)Attribute I also tried componentContext().(put|get)Value and an application scope. Didn't work either.

My DynPage:

  public static class Ralbi1stPageDynPage extends JSPDynPage{

    MyBean myBean_;

    public void doInitialization(){
      getMyBean();
    }

    public void doProcessAfterInput() throws PageException {
      MyBean myBean = getMyBean();
      InputField input = (InputField)getComponentByName("inputName");
      if(input != null) {
        myBean.setTextView("Your name: "+input.getValueAsDataType().toString());
      }
      else
        myBean.setTextView("input not found.");
    }

    public void doProcessBeforeOutput() throws PageException {
      this.setJspName("Ralbi1stPage.jsp");
    }
    
    public void onClick(Event event) throws PageException {
    }
    
    private MyBean getMyBean() {
      IPortalComponentRequest request = (IPortalComponentRequest)this.getRequest();
      MyBean myBean = (MyBean)request.getServletRequest().getSession().getAttribute("myBean");
      if(myBean == null) {
        myBean_ = new MyBean();
        myBean_.setText("Submit");
        request.getServletRequest().getSession().setAttribute("myBean", myBean_);

        myBean = myBean_;
      }
      return myBean;
    }
  }

My JSP:

<%@ taglib uri= "tagLib" prefix="hbj" %>
<jsp:useBean id="myBean" type="com.werum.ralbi.view.MyBean" scope="session"/>

<hbj:content id="myContext" >
  <hbj:page title="PageTitle">
   <hbj:form id="myFormId" >
    <hbj:tray id="example" design="BORDER" width="500" title="NameCheck" isCollapsed="false">
     <hbj:trayBody>
      <br/><font size="-1">Bean: <%=myBean%>/<%=myBean.getText()%>/<%=myBean.getTextView()%><br/></font>
      <hbj:inputField id="inputName" type="String" design="STANDARD" width="100" maxlength="100" tooltip="please enter your name">
      </hbj:inputField>
      <hbj:button id="myButton" text="<%=myBean.getText()%>" onClick="click" tooltip="submit">
      </hbj:button>
      <br/><br/>
      <hbj:textView id="zeile1" encode="false" tooltip="your name">
       <% zeile1.setText(":"+myBean.getTextView()+":"); %>
      </hbj:textView>
     </hbj:trayBody>
    </hbj:tray>
   </hbj:form>
  </hbj:page>
</hbj:content>

My portalapp.xml:

<?xml version="1.0" encoding="utf-8"?>
<application alias="RalbiPortalApplication">
  <application-config>
    <property name="PrivateSharingReference" value="com.sap.portal.htmlb"/>
  </application-config>
  <components>
    <component name="Ralbi1stPage">
      <component-config>
        <property name="ClassName" value="com.werum.ralbi.Ralbi1stPage"/>
        <property name="SecurityZone" value="com.werum.ralbi.Ralbi1stPage/high_safety"/>
        <property name="ComponentType" value="jspnative"/>
        <property name="JSP" value="pagelet/Ralbi1stPage.jsp"/>
      </component-config>
      <component-profile>
        <property name="tagLib" value="/SERVICE/htmlb/taglib/htmlb.tld"/>
      </component-profile>
    </component>
  </components>
  <services/>
</application>

I took the sample from a book, and had to change some details in order to get it run on Version 6.40 SP11.

These hints I got from this forum, but none of them helped to leave in success.

Kind Regards,

Ralf

[Former Member · Accepted solution]

Hi Ralf,

Guess you using NDS to develop JSPDynpage iView.

When you select session or application, it auto creates the Bean initialization stuff!

Also, U need to delete:

<property name="ComponentType" value="jspnative"/>

<property name="JSP" value="pagelet/Ralbi1stPage.jsp"/>

from portalapp.xml (Itz not needed)

If u need a document on how to create One..

ping me on sapmails@gmail.com

Regards,

P.

[Former Member · Accepted solution]

Hi P.,

thanks for your reply, but when I delete these two lines, I get an error-message in EP.

And then the next problem, I can't find the appropriate logfile with the detailed message.

Regards,

Ralf

[detlev_beutner · Accepted solution]

Hi Ralf,

P was absolutely correct, when you develop a JDPDynPage based application, the lines must be deleted! That's definitive!

> I get an error-message in EP

What kind of?

> I can't find the appropriate logfile

> with the detailed message

\usr\sap\<ID>\JC00\j2ee\cluster\server0\log, there the latest default.X.trc

Hope it helps

Detlev

PS: Please consider rewarding points for helpful answers on SDN. Thanks in advance!

[Former Member · Accepted solution]

Hi Detlev,

I found the log but I'm slightly tangled.

I get a ClassCastException when I cast the object that I got from the session to my bean-type.

What's that? My traces tell me, that it's the correct type. It works, when I remove the attrib in doInitialisation and create a new one afterwords.

What kind of class is stored in the session-attribute?

Regards,

Ralf

[detlev_beutner · Accepted solution]

Hi Ralf,

that sounds like a more or less well known problem, see and

Hope it helps

Detlev

[Former Member · Accepted solution]

Hi Detlev,

YES. That's it.

Now my first step didn't stumble anymore.

The serialization problem I didn't had before with other J2EE servers but it makes sense.

Thanks a lot.

Regards,

Ralf

[Former Member · Accepted solution]

Hi Detlev,

I think, I have to revise my euphoria.

I still had the statement

MyBean myBean = request.getSession().getAtt...

in my JSP. When I delete this and use the <jsp:useBean scope="session"> statement, then the bean is empty. In my traces I can see, that two instances of my bean have been created.

Why that?

Another thing: I tried custom taglibs. No way. Not the simplest tag is functioning. I allways get an...

Caused by: com.sapportals.portal.prt.component.PortalComponentException: Error occurs when the jsp parser try to read the jsp
	at com.sapportals.portal.prt.servlets_jsp.server.jsp.JSPCompiler.compile(JSPCompiler.java:96)
	at com.sapportals.portal.prt.servlets_jsp.server.jsp.JSPCompiler.run(JSPCompiler.java:140)
	at com.sapportals.portal.prt.core.broker.JSPComponentItem.compileJSP(JSPComponentItem.java:279)
	at com.sapportals.portal.prt.core.broker.JSPComponentItem.getComponentInstance(JSPComponentItem.java:129)
	at com.sapportals.portal.prt.core.broker.PortalComponentItemFacade.service(PortalComponentItemFacade.java:355)
	at com.sapportals.portal.prt.core.broker.PortalComponentItem.service(PortalComponentItem.java:934)
	at com.sapportals.portal.prt.core.PortalRequestManager.dispatchRequest(PortalRequestManager.java:435)
	... 23 more
Caused by: com.sapportals.portal.prt.servlets_jsp.server.jsp.ParseException: java.lang.NullPointerException
	at com.sapportals.portal.prt.servlets_jsp.server.jsp.TagBeginGenerator.init(TagBeginGenerator.java:147)
	at com.sapportals.portal.prt.servlets_jsp.server.jsp.syntax.xmlsyntax.CustomJspTag.action(CustomJspTag.java:114)

The documentation is slightly rare about taglib.

Regards,

Ralf

[detlev_beutner · Accepted solution]

Hi Ralf,

1.)

(a) provide the actual code which puts the created bean into it's scope

(b) provide the actual JSP code how you try to access the bean

2.) See and

Hope it helps

Detlev

[Former Member · Accepted solution]

That was quick!

Here the init code:

public void doInitialization(){
  System.out.println("---> trc: onInitialization()");
  IPortalComponentRequest request = (IPortalComponentRequest)this.getRequest();
  MyFirstSAPBean myBean = new MyFirstSAPBean();
  myBean.setText("submit");
  request.getServletRequest().getSession().setAttribute("myBean", myBean);
  System.out.println("     myBean created:"+myBean);
  System.out.println("<--- trc: onInitialization()");
}

And here the JSP:

<%@ taglib uri= "tagLib" prefix="hbj" %>

<%@ page import="com.werum.ralbi.view.*" %>

<jsp:useBean id="myBean" class="com.werum.ralbi.view.MyFirstSAPBean" scope="session" />

<% 
   System.out.println("---> JSP: "+myBean);
%>

<hbj:content id="myContext" >
 <hbj:page title="PageTitle">
  <hbj:form id="myFormId" >
   <hbj:inputField id="inputName" type="String" design="STANDARD" width="100" maxlength="100" tooltip="Please enter your name:"/>
   <hbj:button id="myButton" text="<%=myBean.getText()%>" onClick="click" tooltip="submit"/>
  </hbj:form>
 </hbj:page>
</hbj:content>

Thanks a lot.

Regards,

Ralf

[detlev_beutner · Accepted solution]

Hi Ralf,

quick again, that's how I work

scope="session" in the JSP means, that the bean has to be put into the PortalComponentSession, i.e. <i>componentRequest.getComponentSession().putValue(String key, Object value);</i>

Alternatively, you should be able to call putValue on the HttpSession.

See http://help.sap.com/saphelp_nw04/helpdata/en/3a/ec20401fe52402e10000000a1550b0/frameset.htm and http://help.sap.com/saphelp_nw04/helpdata/en/2e/c87f41849d030de10000000a1550b0/frameset.htm for further details.

Hope it helps

Detlev

[Former Member · Accepted solution]

Hi Detlev,

really quick

Now it works. Bean and Tags.

Thanks a lot.

As remarked this are my first steps with EP, have programmed under Tomcat for last 3 years.

Where can I find some documentation concerning these pitfalls, or better to avoid these pitfalls. It is really different as programming under tomcat or Websphere.

The tutorials I've found are partially deprecated.

Kind regards,

Ralf

[detlev_beutner · Accepted solution]

Hi Ralf,

> have programmed under Tomcat for last 3 years.

That similiar how I got into the EP SAP-Java world. Yeah, you have to learn that the implementation is not always following standards...

> Where can I find some documentation concerning

> these pitfalls

I would suggest two things:

(a) Read the developer guide(s) and check out everything "live" on your portal installation. Just to get experience as fast as possible.

(b) Read SDN threads and try to resolve the issues. You will quite fast learn things you can reuse later in your life, which you just wouldn't be aware of otherwise.

Hope it helps

Detlev