RE: Nested logic:iterate tags
Hi,
I just had bad experience with ServletExec 3.0E and nested
iterate tags. When I changed the inner iterate tag back to
scriptlets things startted working again (the code worked fine
under Tomcat 3.2.1).
Is anyone aware of problems with NewAtlanta's handling of custom
tags in general or Struts in particular?
My env:
1. Sun JDK 1.2.2_5/6
2. New Atlanta ServletExec 3.0E
3. Windows 2000 Professional or Sparc Solaris 2.6
4. Jakarta Struts and Jakarta Taglib
Thanks,
--Amos
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, June 06, 2001 5:59 PM
To: [EMAIL PROTECTED]
Subject: Re: Nested logic:iterate tags
Marc,
Here's a sample of nested iterate tags IterateForm.java and
TimeNavDblIter.jsp.
Thanks to Craig et al it's a piece of cake.
john ware
/ TimeNavDblIter.jsp
<%@ page language="java" import = "com.jdware.beans.*" %>
<%@ taglib uri="/WEB-INF/struts-bean.tld" prefix="bean" %>
<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>
<%@ taglib uri="/WEB-INF/struts-logic.tld" prefix="logic" %>
<%
IterateForm instance = new IterateForm();
instance.setName( "yeh baby" );
pageContext.setAttribute("instance", instance,
PageContext.PAGE_SCOPE);
%>
Name:
Address
TypeSize
<% int h = 0; %>
<% h++; %>
<% int i = 0; %>
<% int j = 0; %>
<% j++; %>
<% i++; %>
// end
TimeNavDblIter.jsp
// IterateForm.java
package com.jdware.beans;
import java.util.*;
import org.apache.struts.action.ActionError;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;
import javax.servlet.http.HttpServletRequest;
import com.jdware.util.Trace;
public class IterateForm extends ActionForm {
public String name = "TestMe";
public String address = "Sischo Dr";
public IterateForm(){
foos = Foo.getFoosByMagic();
}
public static class Foo implements Comparable {
public String type;
public int size;
public Foo(){
type="foo";
size=0;
bars = Bar.getBarsByMagic();
}
public Foo( String type, int size ){
bars = Bar.getBarsByMagic();
this.type = type;
this.size = size;
}
public static ArrayList getFoosByMagic(){
ArrayList rtn = new ArrayList();
rtn.add( new Foo("typeA", 42));
rtn.add( new Foo("typeF", 2));
rtn.add( new Foo("typeW", 4));
rtn.add( new Foo("typeH", 0));
rtn.add( new Foo("typeX", 77));
return rtn;
}
public String getType(){return type;}
public void setType( String type ){ this.type = type; }
public int getSize(){ return size; }
public void setSize( int size ){ this.size = size; }
public int compareTo(Object o){
return type.compareTo( ((Foo)o).type );
}
public static class Bar implements Comparable{
/**
*
*/
public String date;
public String getDate(){ return date; }
public void setDate( String date ){ this.date = date; }
/**
*
*/
public String activity;
public String getActivity(){ return activity; }
public void setActivity( String activity ){ this.activity =
activity; }
/**
*
*/
public double hours;
public double getHours(){ return hours; }
public void setHours( double hours ) { this.hours = hours; }
public Bar(){
date = "8/5/50";
activity = "nonsense";
hours = 8.5;
}
public Bar( String date, String activity, double hours ){
this.date = date;
this.activity = activity;
this.hours = hours;
}
public static ArrayList getBarsByMagic(){
ArrayList rtn = new ArrayList();
rtn.add( new Bar("4/3/54", "chores", 8.5));
rtn.add( new Bar("2/5/85", "hotguys", 0.5));
rtn.add( new Bar("6/4/88", "battle", 3.5));
rtn.add( new Bar("8/5/50", "fun", 18.5));
return rtn;
}
public int compareTo(Object o){
return date.compareTo( ((Bar)o).date );
}
public String toString(){
StringBuffer buf = new StringBuffer();
buf.append( " date : " ).append(
RE: Help me defend Struts taglibs!!!
As the local neighborhood taglibs pusher in my company, I came under some scrutiny about the lack of an Else in tags and realised the difficulty about nesting XML tags legally, just as described by Craig in his message below. What I pretty quickly came up with is a "switch" syntax: ... It's not stright-forward if/else, but it is (IMHO): 1. Legal XML 2. Relatively clear as an if/else clause 3. Provides a solution for a more general case of switch/case What do you think? Cheers, --Amos Shapira WebCollage -Original Message- From: Craig R. McClanahan [mailto:[EMAIL PROTECTED]] Sent: Thursday, May 31, 2001 6:18 AM To: '[EMAIL PROTECTED]' Subject: RE: Help me defend Struts taglibs!!! On Thu, 26 Apr 2001, Scott Cressler wrote: > One thing this argument might come down to is why custom tags, especially > for "if...else" stuff (which, BTW, IMHO is not handled real well by the > struts tags...would be nicer to have more flexibility in the conditions you > can check and to have the ability to do else, rather than > .but > that's another discussion :-). In other words, if it is so easy to just > slap some Java in their to do some conditional stuff, why use a clumsy tag. > It turns out to be surprisingly difficult to come up with syntax for an "else" construct that is legal XML syntax and isn't really ugly. There's currently work going on in the JSP Standard Tag Library effort (JSR-052) to create tags that will eventually be known to all containters in the same way that tags like are -- which will also deal with a lot of the performance related concerns. It looks like there will be reasonable ways to do "switch" and "if-else" type processing with them. In the mean time, we can reconsider adding an "else" capability in Struts 1.1, if someone can come up with a good syntax. Craig
RE: How to use the new iterate tag?
Hi, Thanks a lot! That's exactly what I wanted. You said that it seems like an overkill to use a tag, is there another way to access this index? What are the chances to see this tag in the library? Cheers, --Amos > -Original Message- > From: Deadman, Hal [mailto:[EMAIL PROTECTED]] > Sent: Wednesday, May 23, 2001 7:29 PM > To: [EMAIL PROTECTED] > Cc: [EMAIL PROTECTED] > Subject: RE: How to use the new iterate tag? > > > Do you just want to display the index? If you do, I just > wrote a custom tag that does that. It allows me to remove one > of the last instances of scriptlets that I have in my jsps. > It's seems overkill to have a tag that just displays the > iterate counter but oh well. If nothing else, you can use it > as an example of how to access the index of the iterate tag. [ rest deleted ]
RE: Iterating on an Iterator?
Thanks, I mnissed that part - but Iterate can also take an iterator. Sorry about the noise... --Amos > -Original Message- > From: Jim Richards [mailto:[EMAIL PROTECTED]] > Sent: Wednesday, May 23, 2001 12:45 PM > To: [EMAIL PROTECTED] > Subject: Re: Iterating on an Iterator? > > > > takes a collection and can do that for you. > > >Our object model provides an Iterator interface to walk along > >lists (properties of an object or lists of objects). > > > >Does anyone know how can I take advantage of a tag library to > >accept an iterator an iterate using Iterator.hasNext() and > >Iterator.next()? > > > -- > Kumera - a new Open Source Content Management System > for small to medium web sites written in Perl and using XML > http://www.cyber4.org/kumera/index.html >
Iterating on an Iterator?
Hello, Our object model provides an Iterator interface to walk along lists (properties of an object or lists of objects). Does anyone know how can I take advantage of a tag library to accept an iterator an iterate using Iterator.hasNext() and Iterator.next()? Thanks, --Amos Shapira
RE: How to use the new iterate tag?
Thanks, I just tried this and it works great! I still wander how should I go about accessing the index in an "iterate" tag. Cheers, --Amos > -Original Message- > From: Deadman, Hal [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, May 22, 2001 11:37 PM > To: [EMAIL PROTECTED] > Subject: RE: How to use the new iterate tag? > > > You should be using struts-logic.tld, not struts.tld. Never > use struts.tld. > > > -----Original Message- > > From: Amos Shapira [mailto:[EMAIL PROTECTED]] > > Sent: Tuesday, May 22, 2001 1:16 PM > > To: '[EMAIL PROTECTED]' > > Subject: RE: How to use the new iterate tag? > > > > > > I use the TLD extracted from the .jar file, as far as I can > > tell. > > > > > -Original Message- > > > From: Deadman, Hal [mailto:[EMAIL PROTECTED]] > > > Sent: Tuesday, May 22, 2001 6:14 PM > > > To: [EMAIL PROTECTED] > > > Subject: RE: How to use the new iterate tag? > > > > > > > > > Type should be available as an attribute of the iterate tag. > > > Which tld are you using? The tld and the documentation are > > > generated from the same xml file so they shouldn't be out > of sync. > > > > > > I think the iterate tag exposes the index for use by nested > > > custom tags, but I don't know if any tags in struts make use > > > of the exposed index. Maybe you have to write your own tag to > > > access it? > > > > > > Hal > > > > > > > -Original Message- > > > > From: Amos Shapira [mailto:[EMAIL PROTECTED]] > > > > Sent: Tuesday, May 22, 2001 7:19 AM > > > > To: '[EMAIL PROTECTED]' > > > > Subject: How to use the new iterate tag? > > > > > > > > > > > > Hello, > > > > > > > > I'm using Struts-1.0-b2. > > > > > > > > I'm trying to iterate over an array of objects using the > > iterate tag > > > > as follows: > > > > > > > > > > >collection = "<%= headers %>" > > > >type = "some.class"> > > > > > > > > But I get an error like: > > > > > > > > Attribute type invalid according to the specified TLD > > > > > > > > And indeed it looks like the "type" attribute is not specified > > > > in the TLD, contrary to what the documentation says. > > > > When I try to drop the "type" attribute I see in the .java class > > > > that Tomcat defines "header" as a "java.lang.Object" > and obviously > > > > fails later when I access class methods. I also tried to declare > > > > "header" using "useBean", but I get a "variable already defined" > > > > error. > > > > > > > > Does anyone know what am I doing wrong? > > > > > > > > Also, I read in the documentation that now the iteration tag > > > > exposes the current index number, can anyone show me how can > > > > I access this from a JSP page? I couldn't find an example in > > > > the distribution. > > > > > > > > Thanks, > > > > > > > > --Amos Shapira > > > > > > > > > >
RE: How to use the new iterate tag?
I use the TLD extracted from the .jar file, as far as I can tell. > -Original Message- > From: Deadman, Hal [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, May 22, 2001 6:14 PM > To: [EMAIL PROTECTED] > Subject: RE: How to use the new iterate tag? > > > Type should be available as an attribute of the iterate tag. > Which tld are you using? The tld and the documentation are > generated from the same xml file so they shouldn't be out of sync. > > I think the iterate tag exposes the index for use by nested > custom tags, but I don't know if any tags in struts make use > of the exposed index. Maybe you have to write your own tag to > access it? > > Hal > > > -Original Message- > > From: Amos Shapira [mailto:[EMAIL PROTECTED]] > > Sent: Tuesday, May 22, 2001 7:19 AM > > To: '[EMAIL PROTECTED]' > > Subject: How to use the new iterate tag? > > > > > > Hello, > > > > I'm using Struts-1.0-b2. > > > > I'm trying to iterate over an array of objects using the iterate tag > > as follows: > > > > >collection = "<%= headers %>" > >type = "some.class"> > > > > But I get an error like: > > > > Attribute type invalid according to the specified TLD > > > > And indeed it looks like the "type" attribute is not specified > > in the TLD, contrary to what the documentation says. > > When I try to drop the "type" attribute I see in the .java class > > that Tomcat defines "header" as a "java.lang.Object" and obviously > > fails later when I access class methods. I also tried to declare > > "header" using "useBean", but I get a "variable already defined" > > error. > > > > Does anyone know what am I doing wrong? > > > > Also, I read in the documentation that now the iteration tag > > exposes the current index number, can anyone show me how can > > I access this from a JSP page? I couldn't find an example in > > the distribution. > > > > Thanks, > > > > --Amos Shapira > > >
How to use the new iterate tag?
Hello, I'm using Struts-1.0-b2. I'm trying to iterate over an array of objects using the iterate tag as follows: But I get an error like: Attribute type invalid according to the specified TLD And indeed it looks like the "type" attribute is not specified in the TLD, contrary to what the documentation says. When I try to drop the "type" attribute I see in the .java class that Tomcat defines "header" as a "java.lang.Object" and obviously fails later when I access class methods. I also tried to declare "header" using "useBean", but I get a "variable already defined" error. Does anyone know what am I doing wrong? Also, I read in the documentation that now the iteration tag exposes the current index number, can anyone show me how can I access this from a JSP page? I couldn't find an example in the distribution. Thanks, --Amos Shapira
