Call static method from jsp expression
Hi, I'm using adf/bc 10.1.3.4 I'm wanting to call a static method of a class when an af:commandLink is clicked. This action attribute value for this af:commandLink would be an el expression. As an example, let's say I want to call a new static method, named test(), I've added to ADFUtils.
My af:commandLink looks like this:
<af:commandLink action="#{ADFUtils.test}" />
Obviously, this doesn't work. I can describe my actual use case if it would help. For now I'll just say that I don't want to use a managed/backing bean to house this method. How can I create a class to house this method w/o using a managed bean and adding that managed bean reference to the faces-config.xml?? Thanks, James
thanks for the interest john. i'll explain what it is i'm trying to do. I have two web applications, appA and appB, both running in the same app server instance. The apps are related in the sense that once the user logs in thru an sso mechanism, they can 'bounce' back and forth between applications. Not sure if that info is relevant, but I wanted to include it anyhow.
We've created a common banner/header jsp that we include in every page of appA and appB. Included in that header jsp is a logout link (af:commandLink), which will need to execute some code when clicked. Here is where the dilemma starts. We don't really want to have to write the code for the logout in a managed/backing bean because although both applications can use that same bean (we have it set up in the repository so that when a checkout/update is done on either appA or appB, each app, utilizing an svn external rule, would get both the banner jsp and the logout code that goes with it), making good use of the reusability concept, we would also have to add a reference to that backing/managed bean in the faces-config.xml of each application in order for it to be instantiated and used by each app. I was hoping to implement a solution which wouldn't require the developer to have to do any 'setup' on an application by application basis to use the header jsp and the code behind the Logout link. I've described a simple scenario, but in reality we'll have multiple applications, which means multiple places (faces-config.xml) where we'd need to add a reference to the managed bean which contains the logout code. It wouldn't be the end of the world for us if we ended up doing it this way, but I just have a feeling like there may be a better way to implement this so that each application's faces-config doesn't need to be touched. Hope my explanation is clear. thanks for any help you can offer.
Edited by: kcjim on Feb 25, 2009 8:21 AM
Edited by: kcjim on Feb 25, 2009 8:22 AM
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Calling class methods from jsp
hi - this seems like it should be painfully obvious but I am missing something somewhere and can't seem to get it to work.
The end result I am looking for is to be able to call a method similar to how I would do it in PHP or ASP.
To do this I have writte the following class (just as an example) and combpiled it to /WEB-INF/classes/com/example/util/Echo.class:
package com.example.util;
class Echo
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My expectation would be that when I run this page in a browser, I see the text "I'm using my Echo class." printed out on the page. Instead I get the following error:
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[javac] Compiling 1 source file
/var/tomcat4/work/Standalone/localhost/raindance/classtest_jsp.java:47: cannot resolve symbol
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^
1 error
What am I doing wrong?Umm... I'm not entirely sure what you're attempting to do, but it looks like there's some discrepancy between your error message and your code...
RDmail("I'm using my Echo class."); in your code
and
Echo("I'm using my Echo class"); in your error message.
Is this just a cut/paste error?
Also, the main() method is only called from a command line, and will not be run when you instantiate your bean in a JSP. If you want to have your String printed out when you create a new object, you should put the print statement in the constructor. Which would then be called when you created a new object..
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Compilation error while calling static method from another class
Hi,
I am new to Java Programming. I have written two class files Dummy1 and Dummy2.java in the same package Test.
In Dummy1.java I have declared a static final variable and a static method as you can see it below.
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This is program is compiling fine.
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Hi,
Please look at the class below:
public class X
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Think a bean (say BeanZ) that make calls to getY() method without initializing the class X (like this: X.getY() )
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I'm wondering if any collision occurs because of STATIC method? Should I use "SYNCHRONIZED" keyword with it? If so, what about Math.cos() which also is a non synchronized static method ? Shouldn't I use Math.cos() (and the other static methods) in JSP or bean?
Thank you for your help.
Ali SadikHi,
Thank you for your quick answer. Think my class like this:
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public X() {}
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for(int i = 0; i < b.length; i++)
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return ret;
Does it the type of class that you've mentioned ? It makes calculation to produce dynamic result. Shouldn't I use it as static ? If your answer is yes, what about Math.cos()? Doesn't it have dynamic calculation?
Thanks a lot. -
Hi
is it possible to call any method with in the class except handle method from jsp file?You can call , but it would not be a good design approach.A droplet can do the same task for you.
otherwise :
eg :
<%@ page import="com.mypackage.MyClass"%>
for Static access :
<%
String test= MyClass.myMethod();
%>
for normal classes :
<%
MyClass object = new MyClass();
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http://stackoverflow.com/questions/10918526/call-java-method-in-jsp-file
http://www.javaworld.com/javaworld/jw-05-2003/jw-0523-calltag.html?page=2
```
Praveer
Edited by: Praveer Rai on Mar 26, 2013 5:08 PM -
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hello all,
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Calling Java Methods from Stored Procedures
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Calling a method from another file
This is pretty basic stuff but i can't seem to get it right. I am calling a method from another file. The other file IS located in the same folder BUT when i compile i get errors
"cannot find symbol" <===referring to limit and sieve i believe.
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Is "int sieve = PrimeSieve2008.sieve(limit)" the wrong way to call a file?
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Edited by: Simplistic2099 on Apr 3, 2008 7:47 PM
Edited by: Simplistic2099 on Apr 3, 2008 7:49 PMSimplistic2099 wrote:
the other method runs fine:
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count = 0;
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mayBePrime[j] = false;
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} // end if
candidate++;
} // end while
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PRIMES = new int[count];
count = 0;
for (int j = 2 ; j <= limit ; j++ ) {
if ( mayBePrime[j] ) {
PRIMES[count] = j;
count++;
} // end if
} // for
return PRIMES;
} // sieve
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