Struts tags versus JSTL tags

Hi all,
I'm trying to determine the performance and code generation differences between Struts and JSTL tags. Currently I have a very large JSP which is part of a Struts based application and it's teethering on the edge of the 'code too large for method' issue.
Would replacing Struts based tags with JSTL tags reduce the amount of code generated in a jspService method for a JSP? For example replacing
logic:equal or logic:match with c:if test="..."
I would appreciate anyone opinion on this.
Thanks,
Paul

Thanks,
We've already followed those guidelines. It's really more to do a decision by our functional design team who decided to combine the functionality of two pages into one, which is something we should have flagged initially.
Now we are left with this task of attempting to optimise. It's not the
perfect solution.
There is heavy use of logic:equal/match tags throughout the JSP and my initial investigation is that a c:if test="..." seems to generate less
lines of code because there are not as many attributes to set on the
object.
Would anyone agree with me on that?
Thanks,
Paul

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hi
all friends
i am working in struts & i use jstl tag in jsp. i have one problem rise is how to call the form bean value in jsp page by using jstl tag.
i now how to retrive the value through jsp:logic
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</logic:empty>
see * userListForm mean formbaen name.
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You use the jstl core:if or core:choose combined with the EL:
<c:if test="${empty users.userListForm}">
NO USERS FOUND
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Comparision btw Struts and JSTL tags

Hi,
Is there any article or helpful information that any body have come across that have good comparision between struts and JSTL tags? I am trying to find similar JSTL tags to my struts application.
Any help in this regard is appreciated.
Thanks,
-jon

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How to iterate dyna validation form using jstl tag

i have create dyna validation form in struts-config.xml
<form-bean name="DynaValidationForm"
type="org.apache.struts.validator.DynaValidatorForm">
<form-property name="username" type="java.lang.String" />
<form-property name="cityName" type="java.lang.String[]" />
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please help me

posting the same question more than once won't
increase your chances of getting an answer.
sometimes nobody knows or no one is interested in
putting in the time to figure out an answer. your
question might be one of those.
%sometimes I get the feeling that I'm actually helping someone do me out of a job.

Not able to connect to database(MS SQL Server 2000) through JSTL tag

Hi,
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<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core_rt" %>
<%@ taglib prefix="sql" uri="http://java.sun.com/jstl/sql_rt" %>
<sql:setDataSource var="datasource"
driver="com.microsoft.jdbc.sqlserver.SQLServerDriver"
url="jdbc:mssqlserver:sqlserver://SYS57:1433;DatabaseName= sree"
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</sql:query>
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<head>
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</head>
<body>
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      </c:forEach>
    </table>
</body>
</html>error is this:
javax.servlet.ServletException: Unable to get connection, DataSource invalid: "No suitable driver"
     org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:848)
     org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:781)
     org.apache.jsp.firstdb_jsp._jspService(org.apache.jsp.firstdb_jsp:93)
     org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
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     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:802)root cause
javax.servlet.jsp.JspException: Unable to get connection, DataSource invalid: "No suitable driver"
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     org.apache.jsp.firstdb_jsp._jspx_meth_sql_query_0(org.apache.jsp.firstdb_jsp:132)
     org.apache.jsp.firstdb_jsp._jspService(org.apache.jsp.firstdb_jsp:68)
     org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322)
     org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
     org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
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Thanks,
Akshatha

unable to rectify the error........ tried lot but all in vain...still trying........
my current code is:
<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core_rt" %>
<%@ taglib prefix="sql" uri="http://java.sun.com/jstl/sql_rt" %>
<sql:setDataSource var="datasource" driver="com.microsoft.jdbc.sqlserver.SQLServerDriver"
url="jdbc:microsoft:sqlserver://SYS57:1433;databaseName=sree" user="sa"
         password="dfgdfg"/>
<sql:query var="res" dataSource="${datasource}">
SELECT * FROM books
</sql:query>
<html>
<head>
    <title>A First JSP Database</title>
</head>
<body>
    <table border="1">
      <tr>
        <td>id</td><td>title</td><td>price</td>
      </tr>
      <c:forEach items="${res.rows}" var="row">
      <tr>
        <td><c:out value="${row.id}" /></td>
        <td><c:out value="${row.name}" /></td>
        <td><c:out value="${row.author}" /></td>
      </tr>
      </c:forEach>
    </table>
</body>
</html>Thanks,
Akshatha

Assigning value derived from a jstl tag to a local variable

Hi
I want to derive a value using a jstl tag then i want to use that value in a scriplet . how do i do that?
Please anyone let me know if this can be done.

JSTL values will be stored in one of the four scopes, page, request, session, or application. By default they go to the page scope.
Page scope corresponds to the pageContext object in scriptlets, so you should try:
Object value = pageContext.getAttribute("varName");
If it is not in the page scope, then:
request scope == request object in scriptlets.
session scope == session object in scriptlets
application scope == servletContext object in scriptlets.
Each of these objects has a getAttribute method that works the same as the pageContext one above.
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How to write this java code in jsp using jstl tags?

Can anybody help me on this?
I dont know how to check the containsKey using jstl tags?
<%
     LinkedHashMap yearMap     =     (LinkedHashMap)request.getAttribute("yearMap");
     TreeSet nocSet               =     (TreeSet)request.getAttribute("nocSet");
     Iterator     yearMapIt     =     yearMap.keySet().iterator();
     while(yearMapIt.hasNext())
          int yearValue               =     (Integer)yearMapIt.next();
%>
<tr>
          <td><%=yearValue%></td>
<%
          LinkedHashMap monthMap     =     (LinkedHashMap)yearMap.get(yearValue);
          Iterator     nocSetIt     =     nocSet.iterator();
          while(nocSetIt.hasNext())
               String nCase=(String)nocSetIt.next();
               if(monthMap.containsKey(nCase))
                    String count     =     (String)monthMap.get(nCase);
%>
                    <td> <%= count %> </td>
<%           }
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%>
                    <td> 0 </td>
<%
%>
</tr>
<% } %>Edited by: avn_venki on Feb 18, 2008 11:54 PM

<c:forEach var="yearMap" items="${requestScope.yearMap}">
     <th> <c:out value="${yearMap.key}"/> </th>
<bean:define id="monthMap" value="${yearMap.value}"/>
<c:forEach var="nocSet" items="${nocSet}">
then how to write containsKey using tags??

Posting huge data on to JSP page using JSTL tags

Hi,
I have one application where I have to post huge data (approximately 2000 rows of data) into JSP page. I am using JSTL tags and running on Tomcat 5.
It is taking almost 20 to 25 seconds to load the entire page.
Is it the optimal time to load or it could be improved?
Please let me know.
Thanks,
--Subbu.

Hi Evnafets,
Thank you for the response.
Here are the tasks I am doing to display the data on JSP.
0. We are running on Tomcat 5 and the memory size is 1024MB (1GB).
1. Getting the data - I am not performing any database queries. The data is stored in the static cache memory. So the server side response is so quick - less than a milli second.
2. Using Java beans to pass data to the presentation layer (JSP).
3. 10 'if' conditions and 2 'for' loops and 2 'choose' statements are being used in the JSP page while displaying the data.
4. Along with the above, there are 4 javascript files are being used.
5. The jsp file size after rendering the data, is aprox. 160 kb
Hope this information helps you to understand the problem.
Thanks,
--Subbu.

Access JSTL variable outside JSTL tags

hi
I have this jstl tag:
<sql:query var="brands" dataSource="${ds}">
select brand
from carbrand
</sql:query>
i want to manipulate the brands.rowCount without using the <c:set var="count" value="${brands.rowCount}"/>
how can I read the ${brands.rowCount} outside the JSTL
Because I want to use the Math.round, which I think can be use in
<% Math.round(brands.rowCount/3)%>
But I think its not reading the right variable or value?

The variable is put into one of the JSP scope objects. You will be able to access it by using the pageContext.findAttribute("brands") method.
Note: You will have to know the object's type. So look up the API for the sql tag and see what it is.
Note: You will have to use brands.getRowCount() not brands.rowCount.

Problem using JSTL tag libraries with OC4J 9.0.3

Hi
I'm using the JSTL tag libraries with OC4J 9.0.3. I'm using JDeveloper10.1.2. I put the fmt.tld and c.tld in the WEB-INF directory and I'm adding the jstl.jar and standard.jar library to the EAR file. Both tlds have:
<tlib-version>1.0</tlib-version>
<jsp-version>1.2</jsp-version>
And OC4J 9.0.3 is compatible with tlib version 1.0 and jsp version 1.2. When I run the web app I get:
OracleJSP: oracle.jsp.parse.JspParseException: Line # 1, <%@ taglib uri="/WEB-INF/fmt.tld" prefix="fmt"%>
Error: oracle.xml.parser.v2.XMLParseException ( /dataSource.jsp ):
line #:1 column #:48 : FIXED type Attribute value not equal to the default value 'http://java.sun.com/xml/ns/j2ee'.
line #:2 column #:18 : Attribute 'xmlns:xsi' used but not declared.
line #:3 column #:19 : Attribute 'xmlns:acme' used but not declared.
line #:4 column #:27 : Attribute 'xsi:schemaLocation' used but not declared.
line #:7 column #:16 : Attribute 'version' used but not declared.
line #:14 column #:15 : Invalid element 'tag-class' in content of 'tag', expected elements '[tagclass]'.
line #:14 column #:15 : Element 'tag-class' used but not declared.
line #:15 column #:18 : Invalid element 'body-content' in content of 'tag', expected elements '[tagclass]'.
line #:15 column #:18 : Element 'body-content' used but not declared.
line #:16 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:18 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.
line #:18 column #:12 : Element 'type' used but not declared.
line #:22 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:24 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.
line #:24 column #:12 : Element 'type' used but not declared.
line #:28 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:30 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.
line #:30 column #:12 : Element 'type' used but not declared.
line #:34 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:36 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.
Any ideas?

Hi
Thanks for the reply.
I tried it and I get the same error:
OracleJSP: oracle.jsp.parse.JspParseException: Line # 1, <%@ taglib uri="http://java.sun.com/jstl/fmt" prefix="fmt"%>
Error: oracle.xml.parser.v2.XMLParseException ( /dataSource.jsp ):
line #:1 column #:48 : FIXED type Attribute value not equal to the default value 'http://java.sun.com/xml/ns/j2ee'.
line #:2 column #:18 : Attribute 'xmlns:xsi' used but not declared.
line #:3 column #:19 : Attribute 'xmlns:acme' used but not declared.
line #:4 column #:27 : Attribute 'xsi:schemaLocation' used but not declared.
line #:7 column #:16 : Attribute 'version' used but not declared.
line #:14 column #:15 : Invalid element 'tag-class' in content of 'tag', expected elements '[tagclass]'.
line #:14 column #:15 : Element 'tag-class' used but not declared.
line #:15 column #:18 : Invalid element 'body-content' in content of 'tag', expected elements '[tagclass]'.
line #:15 column #:18 : Element 'body-content' used but not declared.
line #:16 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:18 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.
line #:18 column #:12 : Element 'type' used but not declared.
line #:22 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:24 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.
line #:24 column #:12 : Element 'type' used but not declared.
line #:28 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:30 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.
line #:30 column #:12 : Element 'type' used but not declared.
line #:34 column #:15 : Invalid element 'attribute' in content of 'tag', expected elements '[tagclass]'.
line #:36 column #:12 : Invalid element 'type' in content of 'attribute', expected elements '[required, rtexprvalue]'.

How to use sql tag of jstl for inserting data

hello
I want to insert the data in to oracle through jsp using standard sql tags of jstl please help me

1) Go to www.google.com.
2) Enter in that input field "jstl sql tag tutorial" (assuming you want to learn the JSTL SQL tag library).
3) Hit that search button.
4) Explore the results. One of them is http://java.sun.com/j2ee/1.4/docs/tutorial/doc/JSTL7.html

Cannot use jstl tag for jsp page which generated from Human Task

Hi
Plz help me.
I have tried to using jstl in jsp which generate from Human Task and I deploy it to server( by ant on Jdev ) to see task detail in Oracle Worklist application. But when i submit task and then I access to worklist to see task detail, the error has show in page that "OracleJSP: An error occurred. Consult your application/system administrator for support. Programmers should consider setting the init-param debug_mode to "true" to see the complete exception message. " .
I access server to see application.log to see error and I see error show "workflowform: JspServlet: unable to dispatch to requested page: Exception:oracle.jsp.parse.JspParseException: /Header1.jsp: Line # 3, <%@ taglib uri="http://java.sun.com/jstl/core_rt" prefix="c"%> "
How do I fix this error?
PS. I tried to us jstl because I need to connet to database which jstl tag(sql) if somebody has another solution for connect database in task detail page, Please help suggest me.
Thanks
user520932

Is the jstl tag libray loaded in the appsserver?
Can you use jdbc connection like
DataSource ds = ic.lookup("java:comp/env/jdbc/myDB");
Connection con = ds.getConnection();
DataSource ds = (DataSource) org.apache.derby.jdbc.ClientDataSource()
ds.setPort(1521);
ds.setHost("localhost");
ds.setUser("APP")
ds.setPassword("APP");
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http://java.sun.com/docs/books/tutorial/jdbc/basics/connecting.html

Genereting JSTL tags with an XSLT transformation question

Hi there!
I have some XML datas to display in a jsp file.
XML content is of this type:
<message>
<title>A message</title>
</message>
The most elegent way to present them is to transform XML via xslt into xhtml.
(that way I can externally change with ease the message formatting output without changing the jsp)
For that, I use the cool tag
<x:transform>
on each xml file i want to display (with x:foreEach)
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<div class="message">
<h2>A message</h2>
</div>
My problem is now that I want to include custom tags in the generated content!
For exemple:
<div class="message">
<h2>A message<c:out ...></h2>
</div>
My question is:
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Since it is the product of an xslt transformation ,I suppose it won't be executed at all...
Advices greatly appreciated! :)

I'm not sure I understand what you mean when you say "how can I make that xslt generated tag to be executed???"
You've got your XML input and the XSL-T stylesheet that will transform the XML input into an XHTML stream containing JSTL tags.
I'm assuming that you're going to ask a servlet to pass the XML input to the XSL transformer and get the XHTML output stream. Once you have that, the servlet will write the XHTML to the HTTP response output stream, where it'll be rendered by the browser.
I think the key is to make sure that you tell the browser that response type is a JSP (that's the only document type in which it makes sense to put JSTL tags). When the browser gets that JSP, it'll treat it like any other: generate .java code, compile that to a .class file, and then render.
I'm not sure about efficiency, but it sure is an elegant solution. - MOD

JSP tag in a JSTL tag

Hi all,
i need to pass a dynamic key into a jstl object . how can that be achieved? Below are my codes.
<c:if test="${tableValuesTemp.<%=colName%> == 'functCode'}" >
The code above fails. How can i remedy it?
thanks,
wilson

You cannot use jsp expressions that way in a jstl tag.
You'll have to set the value of the expression as a scoped attribute and then use the square bracket notation in your jstl tag.
<%
pageContext.setAttribute("colName", colName);
%>
<c:if test="${tableValuesTemp[colName] == 'functCode'}" > ram.

Use jstl tags in jsf page

I have h:dataTable in each row of which i'd like to output row data as text, inputfield or link depending on row data type
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                                        <f:param value="itemName"/>
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                                    <h:outputText value="#{wrapper.data}" styleClass="basic_thin"/>
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                                <c_rt:when test="#{wrapper.type==2}">
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                        </h:column>
                     </h:dataTable>trying to use jstl tags but unsuccessfull. Is it ever possible user jstl tags in jsf tags like listed above

Replace the c:choose block by<h:outputText value="#{wrapper.data}" styleClass="basic_thin" rendered="#{wrapper.type == 0}" />
<h:inputText value="#{wrapper.data}" styleClass="basic_thin" style="width:160px" rendered="#{wrapper.type == 1}" />
<h:outputLink value="#{wrapper.data}" rendered="#{wrapper.type == 2}">
    <h:outputText value="#{msg.userorders_link}" styleClass="basic_thin"/>
</h:outputLink>

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