Problem Calling Query in Custom Tag

I am using this code to call a custom tag called
broadcast.cfm
<cf_broadcast query="fe" orgID = "4">
The query fe is an included file on my site and is available
to the page I'm calling the custom tag from.
In the custom tag I am referencing the query like:
<cfloop query="#attributes.query#">
but I keep getting this error:
"The value of the attribute query, which is currently "fe",
is invalid. "
I must be missing something really simple here but can't
figure out what.

quote:
Originally posted by:
-==cfSearching==-
rdk8487 wrote:
> In the custom tag I am referencing the query like:
> <cfloop query="#attributes.query#">
> but I keep getting this error:
> "The value of the attribute query, which is currently
"fe", is invalid. "
It is a scoping problem. The query is defined in the calling
page. To access it by name, within the custom tag, use the "caller"
scope.
<cfloop query="caller.#attributes.nameOfTheQuery#">
If the query object is passed to the custom tag via an
attribute you shouldn't need the caller scope. See attached sample.

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<pre>
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Edited by: CharMow on Feb 11, 2009 5:14 AM

Hi,
I am also getting the same error, when we move to OC4J 10.1.3.
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Following the stack trace..
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Edited by: Get2win4world on Dec 15, 2009 1:12 AM

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I have found a workaround.
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<log:debug category="my.webapp.ousearch.taglib" message="Tag library called, starting operations..." />
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          > parameter, the tag works fine but when I use the expression, the expression
          > gets evaluated but the tag itself does not resulting in the tag being shown
          > in my output.
          >
          > For example:
          >
          > <jsp:forward page="www.slashdot.org"/> works
          >
          > <jsp:forward page="<%=request.getParameter("DESTINATION")%>"/>
          > places the following into my html output
          > <jsp:forward page="www.slashdot.org"/>
          >
          > Can someone please tell me what I am doing wrong or at least offer some
          > debugging hints?
          >
          > Thanks in advance!
          >
          > --
          > Jacob Meushaw
          Jeff Smith
          [email protected]
          BEA Systems, Inc.
          720-565-6613

Nested Custom Tags

Hello,
I have a custom tag that I've written that has some
attributes. I want to nest that tag inside of itself, and access
the attibutes of the parent tag. However, when I try to access the
parent tag's data from the child all I get is the child tag's data!
If there are two of the same custom tags in the context stack, is
it possible to access one from the other? Thanks for your help.
Tim

> I can't use the
> CALLER scope, as that references the page that called
the first custom tag, no
> matter how deeply nested I am.
I think you should test the advice, before you make
assertions like this.
The CALLER scope refers to the variables scope of the
template that called
the currently executing custom tag. If your calling stack is
like this:
index.cfm
customTagA.cfm
customTagB.cfm
Then the situation is this:
1) In index.cfm: no caller scope.
2) In customTagA.cfm: caller scope references index.cfm's
variables scope.
3) custoTagB.cfm: caller scope references customTagA.cfm's
variables scope
(NOT index.cfm's one).
Similarly, if your calling stack is like this:
index.cfm
customTag.cfm (*)
customTag.cfm
customTag.cfm
customTag.cfm
Then the caller scope in each customTag.cfm instance refers
to the
variables scope of the file above it. The only caller scope
that
references index.cfm's variables scope is the customTag
instance marked
with (*).
If I understand your requirement, this is what you want. This
is why I
suggested it.
Adam

Custom Tag Capitalization Problem..

All,
          OS: Windows 2000
          App Server: Weblogic 6.0 sp 2
          JDK: 1.3 (and tried 1.3.1)
          I have a set of custom tags that run fine when I use them on an app server (such as Enhydra) with JDK 1.2.2, but when I switch to JDK 1.3.x, which weblogic 6.x requires, they suddenly start generating errors with attributes which have capitalized letters in them. For example, in my taglib I have:
          <attribute>
          <name>closeConnection</name>
          <required>false</required>
          <rtexprvalue>true</rtexprvalue>
          </attribute>
          and in the support class I have:
          * Get the value of closeConnection.
          * @return value of closeConnection.
          public boolean getCloseConnection() {
          return closeConnection;
          * Set the value of closeConnection.
          * @param v Value to assign to closeConnection.
          public void setCloseConnection(String v) {
          if(v.toUpperCase().equals("TRUE")){
          this.closeConnection = true;
          } else {
          this.closeConnection = false;
          When I go to the page that this tag is on, I get the following output:
          Parsing of JSP File '/index.jsp' failed:
          /index.jsp(1): Error in using tag library uri='/cwerks' prefix='cwerks': There is no setter method for property 'closeconnection', for Tag class 'net.cwerks.taglib.MyTag'
          probably occurred due to an error in /index.jsp line 1:
          <%@ taglib uri="/cwerks" prefix="cwerks" %>
          Thu Aug 02 19:06:52 PDT 2001
          Note that the 'closeconnection' is all lowercase despite the fact that it is upper case in the tld and in the class itself.
          I came across a similar problem in weblogic 5.1 when I upgraded from JDK 1.2.2 to JDK 1.3. I tried changing the JDK for weblogic 6.0 sp 2 to 1.2.2, but a dll was missing. I also tried switching it to 1.3.1, but that did not help. It seems like introspection may have changed slightly between the two version. I'm shocked, and a bit suspicious, that I haven't seen this problem all over the newsgroups. Anyone else seen this?
          Thank you,
          Carson Gross
          [email protected]
          [att1.html]


A solution presents itself:
          The problem was NOT with capitalization. Instead, the problem was as
          follows:
          My method was for setting a boolean, but I took a string so that people
          wouldn't have to type:
          <mytags:tag foo="<%=true%>" />
          instead, they could type:
          <mytags:tag foo="true" />
          which would call the setter method with a string "true", which would be then
          converted to a boolean within my class.
          So my setter has this signature:
          public void setFoo(String s)
          and my getter has this signature:
          public boolean getFoo() /* I know this isn't standard, but isFoo doesn't
          sound good to me*/
          I can't tell if it's because JavaBeans changed slightly between jdk 1.2.2
          and 1.3.x, or if Weblogic changed the way that they do things (I suspect the
          latter, since I had things working fine in WL 5.2 w/ jdk 1.2.2 and then
          things broke with WL 5.2 w/ jdk 1.3), but this no longer returns foo as a
          valid property to be set, and since weblogic 6.x relies on JavaBeans,
          instead of straight up introspection, it barfs. (I found this out by using
          jad/emacs, a wicked combination for those who want to poke around in jars).
          Anyway, I hope I can save someone else who has this same, albeit
          specialized, problem a lot of pain by my discovery. Your getters and
          setters better be of the same type with custom tags, or weblogic w/ jdk1.3.x
          is gonna barf when parsing the tld.
          Cheers, and thank God that's behind me,
          Carson Gross
          [email protected]
          ====================================================
          "Carson Gross" <[email protected]> wrote in message
          news:[email protected]...
          The plot grows thicker...
          The tags work fine on Tomcat 3.2.2
          I deploy the example tags that came with wl60 that have more than one
          capital letter in thier attributes, and they work fine. But my tag library
          stubbornly insists on not working so long as I keep the attributes with more
          than one capital letter in. If I remove the offending attributes, or change
          them to have only one capital letter, they work, but this is not an
          acceptable solution. (I guess.)
          I even created an simple introspection class to make sure that the acutal
          methods were there. They were.
          I am at a complete loss here... I guess it's tomcat for now.
          Cheers,
          Carson Gross
          [email protected]
          "Carson Gross" <[email protected]> wrote in message
          news:[email protected]...
          All,
          OS: Windows 2000
          App Server: Weblogic 6.0 sp 2
          JDK: 1.3 (and tried 1.3.1)
          I have a set of custom tags that run fine when I use them on an app server
          (such as Enhydra) with JDK 1.2.2, but when I switch to JDK 1.3.x, which
          weblogic 6.x requires, they suddenly start generating errors with attributes
          which have capitalized letters in them. For example, in my taglib I have:
          <attribute>
          <name>closeConnection</name>
          <required>false</required>
          <rtexprvalue>true</rtexprvalue>
          </attribute>
          and in the support class I have:
          * Get the value of closeConnection.
          * @return value of closeConnection.
          public boolean getCloseConnection() {
          return closeConnection;
          * Set the value of closeConnection.
          * @param v Value to assign to closeConnection.
          public void setCloseConnection(String v) {
          if(v.toUpperCase().equals("TRUE")){
          this.closeConnection = true;
          } else {
          this.closeConnection = false;
          When I go to the page that this tag is on, I get the following output:
          Parsing of JSP File '/index.jsp' failed:
          /index.jsp(1): Error in using tag library uri='/cwerks' prefix='cwerks':
          There is no setter method for property 'closeconnection', for Tag class
          'net.cwerks.taglib.MyTag'
          probably occurred due to an error in /index.jsp line 1:
          <%@ taglib uri="/cwerks" prefix="cwerks" %>
          Thu Aug 02 19:06:52 PDT 2001
          Note that the 'closeconnection' is all lowercase despite the fact that it is
          upper case in the tld and in the class itself.
          I came across a similar problem in weblogic 5.1 when I upgraded from JDK
          1.2.2 to JDK 1.3. I tried changing the JDK for weblogic 6.0 sp 2 to 1.2.2,
          but a dll was missing. I also tried switching it to 1.3.1, but that did not
          help. It seems like introspection may have changed slightly between the two
          version. I'm shocked, and a bit suspicious, that I haven't seen this
          problem all over the newsgroups. Anyone else seen this?
          Thank you,
          Carson Gross
          [email protected]

Dynamic include in a custom tag, called from a jsp

Hello, I would like to be able to dynamically include other jsp's from within a custom tag that I create. is this possible?
in a jsp page i would just write <%@ include file="file.jsp" %> and all would be ok... but if i do an out.println( "<%@ include file=\"file.jsp\" %>" ); inside a custom tag bean then it doesn't work. it just prints out the command to the page as plain text.
I do understand why this is happening, but can anyone offer me a way around this problem?
Thanks in advance,
Randy

That's actually the same result as you get with a normal include - The method I suggested is a dynamic include similar to the <jsp:include> tag, not the <%@ include %> tag.
When you use a dynamic include, the included page is compiled and 'invoked' as serarately, and the result is what gets included, not the actual source. To get the behaviour you want would require an include directive (the <%@ include %> tag) which I don't think has an equivalence you can use inside a custom tag.
What you can do is pass attributes from the tag class like this:
pageContext.setAttribute(<name>, <object>, pageContext.REQUEST_SCOPE);
and then remove them after the include using pageContext.removeAttribute.
I'm not certain, but this implies that if you declare your variables with a <jsp:usebean> tag with request scope, instead of normal Java variable declarations, you should be able to use them in the page included by the custom tag.
*** in the jsp ***
<jsp:useBean id="myVar" scope="request" class="java.lang.String" />
<% myVar = "Something"; %>
// Now call the tag which uses the pageContext.include() mehtod.
*** end ***
*** in the include ***
<jsp:useBean id="myVar" scope="request" class="java.lang.String" />
<%= myVar + " something else" %>
*** end ***
Let me know if it works.

Problem with optional attribute caching on a custom tag

Hello,
I've created a tag by extending TagSupport. I have one attribute that is optional. I'm having a problem with this attribute since the tag is cached. If the value is not specified in the tag, it is always using the previous value from the past request.
I understand why this is happening, but I wonder if there is anyway to reset this value besides doing it at the end of the doStartTag or in the doEndTag methods? I simply want it to be an empty string if it is not in the request.
Thanks,
Tim

Thats abit overkill in my opinion.Probably yes, but its a cleaner option. In case your doEndTag handles custom exceptions, you would anyhow need to put this code in a finally block, right ?
public int doEndTag() throws JspException {
try {
call some methods that throws other checked exceptions;
}catch(Exception1 e){
throw JspException(e);
}catch(Exception2 e){
//log and ignore
}finally{
//clean up here
return an int;
Having said that, different containers implement the spec a bit differently. For example, in our project, we use weblogic and for wl, we put our clean up code in the release() method which according to the spec, needs to be called only before gc. Weblogic implementation is a bit different - its called after doEnd() for every use of the tag.
This is from jsp spec regarding tag life cycle especially with reuse
Some setters may be called again before a tag handler is reused. For
instance, setParent() is called if it�s reused within the same page but at a dif-ferent
level, setPageContext() is called if it�s used in another page, and
attribute setters are called if the values differ or are expressed as request-time
attribute values.
�Check the TryCatchFinally interface for additional details related to exception handling and resource management.
cheers,
ram.
}

Custom Tag -- Custom Component problems with iframes

I have a "project" component that originally iterated over a list of models and created/renderered the corresponding (and fairly complex) interactive UI components for those models. On the client-side, the output from these were then organized neatly into "tabs" via CSS ... all on one page. Since these UI Components are so hefty, when any iteraction was done on one of them, the whole page had to re-render and things got just plain slow. To get around this limitation, I decided to have my "project" component no longer create the UI components himself, but instead generate an IFRAME that points to a page that will generate a single component. This way, any iteraction will just cause that single IFRAME to refresh.
Due to the fact that an IFRAME can only be populated by using the src attribute, I have created a page that contains a JSF View (<faces:view>) and inside is a single custom tag of mine (<mine:displayView>). Let's call this page singleDisplayView.jsf. I create iframes that point to singleDisplayView.jsf with different request params for each (singleDisplayView.jsf?modelName=Foo, singleDisplayView.jsf?modelName=Bar, etc.)
The displayView tag has one attribute called requestQueryString and I use the tag like so:
<t:displayView requestQueryString="<%=request.getQueryString()%>" />The displayView tag's class is DisplayViewTag. In DisplayViewTag::setProperties(UIComponent uiComponent) method, I get the model name out of the request map and set this property on the UIComponent.
The problem is that I'm noticing that as the main page (that contains these frames) loads, setProperties() is only being called twice. After that, the components created by subsequent iframes just seem to be using the modelName from the second frame.
Is there a syncronization issue I don't understand?
Any ideas?
Any help would be much appreciated.
Thanks in advance,
Mark

On a possibly related note, I read this in an article of the JSF application lifecycle:
In the first phase of the JSF lifecycle -- restore view -- a request comes
through the FacesServlet controller. The controller examines the request and
extracts the view ID, which is determined by the name of the JSP page.Could it be that the lifecycle is trying to reuse components from a single view, since all these iframes are pointing to the same page?

Calling jsp custom tag from jsp expression

hi there,
I have a problem calling oracle(or any other) custom tag from inside a jsp expression.(i.e.)embeding <jbo:tagname...> into <%......%>.
For example:
I need to get the value of a jsp parameter, but the parameter name is dynamic (retrieved from a DataBase)
So I though it would be something link that:
<%=request.getParameter(<jbo:ShowValue datasource="ds" dataitem="ParamName" ></jbo:ShowValue>) %>
where <jbo:ShowValue is an Oracle custom tab that retrieves the value of a certain dataItem(certain field).
But it does not work.........
if any body can tell me how to overcome, or work around it, I'll be so pleased.
Regards,
Remoun Anwar

Hi,
You get the custom tag output into a hidden variable (say 'key') and use the request.getParameter("key")
Hope u got the answer...
Regards
ravi

Problem Calling Query in Custom Tag

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