Logic tags and string properties
It seems that it is not possible to use the logic tags to test is this property either null or an empty string?. Using logic:present, I can determine that some value is present, but as far as I can tell, there is no way to test for an empty string. Specifying value= for tags such as notEqual seems to result in a complaint that a required attribute has not been specified. (Is this correct, or is this a bug in Resin, the container I'm using?) So, I had a couple of ideas for solving this, and I'd like to hear what people think. 1) Modify the present and notPresent tags such that the empty string is equivalent to null for the purposes of this test, if in fact the specified property is a String. This might break things, though - I'm not sure. 2) Define two new logic tags - perhaps empty and notEmpty - which define emptiness as a property being either null or the empty string. Unlike present and notPresent, these tags would only work with the name and property attributes (i.e. not cookie, parameter, etc), since the others don't really make sense distinct from present and notPresent. The second option appeals to me more, because it seems somewhat cleaner than muddying the definition of presence to include type-specific values. Comments, anyone? -- Martin Cooper
Re: Extensions to Struts
hi, this sounds very interesting to me. So, if you don't mind, i'd like to take a look. regards stefan werner - Original Message - From: Roland Huss [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, May 22, 2001 10:49 PM Subject: Extensions to Struts Ahoi, first all thanx for this real fantastic framework, excellent work!. We here at ConSol are developing a web frontend for our helpdesk software based on struts and for the time being we have about 30 actions, 35 custom tags, 110 JSP-Pages (without any explicite java code!) and appr. 20k lines of Java code and it turned out that struts was a great support from the very beginning. In course of the development during the last three month, we made some extensions, which we would happily contribute to struts. Our extensions are listed below briefly. If there's some interest in some of them, please leave a note (note that I will be absent till wednesday in a week, so don't expect a response before) * Followups. Followups are a simple mechanism for an action to return to the place before it was called. Therefore we implemented a FollowupStack which is passed around in URLs and Forms (as hidden parameters). An action only needs simply to call getFollowup() in its perform() method to get a forward to the previous action. (Therefore FormTag and Action was extended). * Action documentation. For documentation of actions, we introduced three new javadoc tags: @input (input parameters expected by this action in its request) , @output (results put into request scope) and @forward (possible forwards of this action). To support these new tags we've written two javadoc Doclets: The first is extending the standard doclet for rendering an HTML table in the class documentation in javadoc. The other one creates XML-output, which we use with an XSL stylesheet to convert it to the stylebook DTD for the online documentation. * Hidden Parameters. Our extension of Action has an addHiddenParameter() method which put hidden parameters into request scope which our subclassed FormTag renders as HTML-Tags. With this method it is very easy to push parameters around to several actions (without polluting session scope). * Image Buttons. This an extension to SubmitTag for rendering image buttons and handling enabled/disabled buttons based on the existance of some object stored in request scope. Our actions can check for the trigger of a submit button regardless whether it was submitted as a submit button or an image-map. * Extra parameters in URLs. Our extended Action gives subclasses a change to append extra parameters to a forward by overriding a getExtraParameters() which will be appended to a forward. * From action to JSP. Not really an extension, but it proved for us to be very useful to stick to the simple paradigm, that a page is only accessed via an action and any JSP-Page is only referenced via an action. JSP pages are really only used for rendering the result calculated by the previous action, which passes them to the JSP page by putting them into request scope. Though it might look rather restrictive, this design descision proved to be very useful mainly due to its simplicity. Well, thats all I remember for the moment. We developed some custom tags, which might prove to be useful on its own (and not only for our application), but that's another story. cu -- ...roland huss consol.de
RE: html:errors/ tag
Hi I have written a subclass of org.apache.struts.util.MessageResources and also a subclass of org.apache.struts.util.MessageResourcesFactory, and made my implementation so that when html:errors/ tag is called it gets the error message from my database instead of the ActionResources.properties file. But the problem that I have got now is, How do I set that up in Struts and which XML file or other file have I to modify. Could you please help me out in this. Thanks Kanna You can subclass org.apache.struts.util.MessageResources to provide your own database implementation of a resource bundle (as opposed to the common properties implementation via org.apache.struts.util.PropertyMessageResources), put an instance of your subclass in a servlet context (application-scope) attribute, and then use the html:errors tag's bundle attribute to specify the name you gave to the servlet context (application-scope) attribute. At least that should be the theory behind it, though I have not done it myself. -- Stoehr P.S. You could also have the application resource bundle be an instance of your MessageResources subclass by creating a subclass of org.apache.struts.util.MessageResourcesFactory that creates instances of your MessageResources subclass, and then specify the new factory in the ActionServlet's factory init parameter. -Original Message- From: SESHADRI Sudarshan [mailto:[EMAIL PROTECTED]] Sent: Tuesday, May 22, 2001 03:52 AM To: '[EMAIL PROTECTED]' Subject: RE: html:errors/ tag Hi Kanna please send me the answer if u find it. thanks Sudarshan tks Sudarshan Tel: office : 9218 6823Fax: 9218 6455 / 9218 6916 Email: [EMAIL PROTECTED] -Original Message- From: Muthu Kannappan [mailto:[EMAIL PROTECTED]] Sent: Wednesday, 23 May 2001 8:42 To: [EMAIL PROTECTED] Subject: html:errors/ tag Hi I have been trying to use struts and wanted to use the html:errors/ tag. I wanted to the error messages to be read from a database instead of the ActionResources properties file. Could you let me know what exactly I am suppose to do to achive that. I wanted to changed the code at the place where it was looking for the properties files and make it look into the database. Could any one suggest me how to do that or has anybody done that already. Thanks Kanna Get free email and a permanent address at http://www.netaddress.com/?N=1
Re: Logic tags and string properties
From: Martin Cooper [EMAIL PROTECTED] Reply-To: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Logic tags and string properties Date: Wed, 23 May 2001 00:12:59 -0700 It seems that it is not possible to use the logic tags to test is this property either null or an empty string?. Using logic:present, I can determine that some value is present, but as far as I can tell, there is no way to test for an empty string. Specifying value= for tags such as notEqual seems to result in a complaint that a required attribute has not been specified. (Is this correct, or is this a bug in Resin, the container I'm using?) Tomcat and Orion have no problems with the value= so maybe it is a bug in Resin? Grtz _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
RE: html:errors/ tag
Sounds like you want the application resource bundle to be an instance of your MessageResource subclass. In that case, you should just have to specify your MessageResourcesFactory subclass fully qualified name for the factory init parameter of the ActionServlet (see http://jakarta.apache.org/struts/userGuide/building_controller.html#dd_confi g_servlet). -- Stoehr -Original Message- From: Muthu Kannappan [mailto:[EMAIL PROTECTED]] Sent: Wednesday, May 23, 2001 07:13 PM To: [EMAIL PROTECTED] Subject: RE: html:errors/ tag Hi I have written a subclass of org.apache.struts.util.MessageResources and also a subclass of org.apache.struts.util.MessageResourcesFactory, and made my implementation so that when html:errors/ tag is called it gets the error message from my database instead of the ActionResources.properties file. But the problem that I have got now is, How do I set that up in Struts and which XML file or other file have I to modify. Could you please help me out in this. Thanks Kanna You can subclass org.apache.struts.util.MessageResources to provide your own database implementation of a resource bundle (as opposed to the common properties implementation via org.apache.struts.util.PropertyMessageResources), put an instance of your subclass in a servlet context (application-scope) attribute, and then use the html:errors tag's bundle attribute to specify the name you gave to the servlet context (application-scope) attribute. At least that should be the theory behind it, though I have not done it myself. -- Stoehr P.S. You could also have the application resource bundle be an instance of your MessageResources subclass by creating a subclass of org.apache.struts.util.MessageResourcesFactory that creates instances of your MessageResources subclass, and then specify the new factory in the ActionServlet's factory init parameter. -Original Message- From: SESHADRI Sudarshan [mailto:[EMAIL PROTECTED]] Sent: Tuesday, May 22, 2001 03:52 AM To: '[EMAIL PROTECTED]' Subject: RE: html:errors/ tag Hi Kanna please send me the answer if u find it. thanks Sudarshan tks Sudarshan Tel: office : 9218 6823Fax: 9218 6455 / 9218 6916 Email: [EMAIL PROTECTED] -Original Message- From: Muthu Kannappan [mailto:[EMAIL PROTECTED]] Sent: Wednesday, 23 May 2001 8:42 To: [EMAIL PROTECTED] Subject: html:errors/ tag Hi I have been trying to use struts and wanted to use the html:errors/ tag. I wanted to the error messages to be read from a database instead of the ActionResources properties file. Could you let me know what exactly I am suppose to do to achive that. I wanted to changed the code at the place where it was looking for the properties files and make it look into the database. Could any one suggest me how to do that or has anybody done that already. Thanks Kanna Get free email and a permanent address at http://www.netaddress.com/?N=1
Re: Logic tags and string properties
On Wed, 23 May 2001, Martin Cooper wrote: It seems that it is not possible to use the logic tags to test is this property either null or an empty string?. Using logic:present, I can determine that some value is present, but as far as I can tell, there is no way to test for an empty string. Specifying value= for tags such as notEqual seems to result in a complaint that a required attribute has not been specified. (Is this correct, or is this a bug in Resin, the container I'm using?) This is ultimately due to a restriction on the way that jsp:setProperty name=beanname property=*/ works, which I copied in the BeanUtils and PropertyUtils classes. As the properties are being copied, if the input value is a zero length string, it is *not* copied. Changing this behavior now would be very likely to break existing code, so I think we need to deal with it. But, your question is more general in scope because the input beans could come from the application as well. So, I had a couple of ideas for solving this, and I'd like to hear what people think. 1) Modify the present and notPresent tags such that the empty string is equivalent to null for the purposes of this test, if in fact the specified property is a String. This might break things, though - I'm not sure. 2) Define two new logic tags - perhaps empty and notEmpty - which define emptiness as a property being either null or the empty string. Unlike present and notPresent, these tags would only work with the name and property attributes (i.e. not cookie, parameter, etc), since the others don't really make sense distinct from present and notPresent. The second option appeals to me more, because it seems somewhat cleaner than muddying the definition of presence to include type-specific values. A third option would be to add an empty attribute to the logic:present and logic:notPresent tags, which tells them how to treat empty strings. The default, of course, would be the current behavior. Comments, anyone? -- Martin Cooper Craig
RE: html:errors/ tag
I haven't done this, but if you look in the comments at the start of ActionServlet it say you need to add a factory parameter to the web.xml file, something like this: servlet servlet-nameaction/servlet-name servlet-classorg.apache.struts.action.ActionServlet/servlet-class init-param param-nameapplication/param-name param-valuemyApp.ApplicationResources/param-value /init-param init-param param-nameconfig/param-name param-value/WEB-INF/struts-config.xml/param-value /init-param init-param param-namefactory/param-name param-valuemyPackage.myMessageResourcesFactory/param-value /init-param load-on-startup2/load-on-startup /servlet Niall -Original Message- From: Muthu Kannappan [mailto:[EMAIL PROTECTED]] Sent: 24 May 2001 00:13 To: [EMAIL PROTECTED] Subject: RE: html:errors/ tag Hi I have written a subclass of org.apache.struts.util.MessageResources and also a subclass of org.apache.struts.util.MessageResourcesFactory, and made my implementation so that when html:errors/ tag is called it gets the error message from my database instead of the ActionResources.properties file. But the problem that I have got now is, How do I set that up in Struts and which XML file or other file have I to modify. Could you please help me out in this. Thanks Kanna You can subclass org.apache.struts.util.MessageResources to provide your own database implementation of a resource bundle (as opposed to the common properties implementation via org.apache.struts.util.PropertyMessageResources), put an instance of your subclass in a servlet context (application-scope) attribute, and then use the html:errors tag's bundle attribute to specify the name you gave to the servlet context (application-scope) attribute. At least that should be the theory behind it, though I have not done it myself. -- Stoehr P.S. You could also have the application resource bundle be an instance of your MessageResources subclass by creating a subclass of org.apache.struts.util.MessageResourcesFactory that creates instances of your MessageResources subclass, and then specify the new factory in the ActionServlet's factory init parameter. -Original Message- From: SESHADRI Sudarshan [mailto:[EMAIL PROTECTED]] Sent: Tuesday, May 22, 2001 03:52 AM To: '[EMAIL PROTECTED]' Subject: RE: html:errors/ tag Hi Kanna please send me the answer if u find it. thanks Sudarshan tks Sudarshan Tel: office : 9218 6823Fax: 9218 6455 / 9218 6916 Email: [EMAIL PROTECTED] -Original Message- From: Muthu Kannappan [mailto:[EMAIL PROTECTED]] Sent: Wednesday, 23 May 2001 8:42 To: [EMAIL PROTECTED] Subject: html:errors/ tag Hi I have been trying to use struts and wanted to use the html:errors/ tag. I wanted to the error messages to be read from a database instead of the ActionResources properties file. Could you let me know what exactly I am suppose to do to achive that. I wanted to changed the code at the place where it was looking for the properties files and make it look into the database. Could any one suggest me how to do that or has anybody done that already. Thanks Kanna Get free email and a permanent address at http://www.netaddress.com/?N=1
SourceForge: Project Info - Ruby Web Application Framework
Just interesting. The charter of the project says: Based on the Jakarta Struts project, the Ruby Web Application framework is a framework for developing web/wap applications founded in the Ruby programming language. http://sourceforge.net/projects/ruby-waf/
