A simple example which shows how to implement your own JSP custom tag with the help of Jython.
Download
Copy to clipboard1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | # DemoTag.py
from javax.servlet.jsp.tagext import TagSupport
class DemoTag(TagSupport):
def __init__(self):
self.context = None
self.parentTag = None
def doStartTag(self):
out = self.context.out
out.print("Hello World from Jython Tag.")
return self.SKIP_BODY
def setPageContext(self, context):
self.context = context
def setParent(self, parent):
self.parentTag = parent
def getParent(self):
return self.parentTag
|
Setup instructions:
(1) generate and compile java class from Jython source jythonc -p jythonsupport DemoTag.py (make sure you have jython.jar available on your CLASSPATH)
(2) put the generated java byte code to the {webapp}/WEB-INF/classes/jythonsupport directory
(3) define the new jython tag in your tag library descriptor file (TLD) add the following fragment
< tag > < name > jydemo < /name > < tag-class > jythonsupport.DemoTag < /tag-class > < body-content > EMPTY < /body-content > < description > A demo custom tag written in Jython. < /description > < /tag >
(4) write a 'normal' JSP using the new tag :-)
[Tested this with Tomcat 4.0.3 / JDK 1.4 / Jython 2.1]
does this really work? I cannot get this code to work. Using Jython 2.1 Tomcat 4.1. I get the following errors:
C:\Tomcat 4.1\work\Standalone\localhost\jythontest\jython_jsp.java:74: cannot resolve symbol symbol : method setPageContext (javax.servlet.jsp.PageContext) location: class jythonsupport.DemoTag _jspx_th_app_jydemo_0.setPageContext(pageContext); ^ C:\Tomcat 4.1\work\Standalone\localhost\jythontest\jython_jsp.java:75: cannot resolve symbol symbol : method setParent (I cannot get this code to work. Using Jython 2.1 Tomcat 4.1. I get the following errors:
C:\Tomcat 4.1\work\Standalone\localhost\jythontest\jython_jsp.java:74: cannot resolve symbol symbol : method setPageContext (javax.servlet.jsp.PageContext) location: class jythonsupport.DemoTag _jspx_th_app_jydemo_0.setPageContext(pageContext); ^ C:\Tomcat 4.1\work\Standalone\localhost\jythontest\jython_jsp.java:75: cannot resolve symbol symbol : method setParent (