org.zkoss.jsp.zul
Class InitTag

java.lang.Object
  javax.servlet.jsp.tagext.SimpleTagSupport
      org.zkoss.jsp.zul.impl.AbstractTag
          org.zkoss.jsp.zul.InitTag

All Implemented Interfaces:

javax.servlet.jsp.tagext.DynamicAttributes, javax.servlet.jsp.tagext.JspTag, javax.servlet.jsp.tagext.SimpleTag

public class InitTag
extends AbstractTag
implements javax.servlet.jsp.tagext.DynamicAttributes

A Tag map to the ZK Initiator. Implemented by an initiator that will be invoked if it is specified in the init directive.

<z:init class="MyInit" />

Once specified, an instance inside this tag is created and Initiator.doInit(org.zkoss.zk.ui.Page, java.lang.Object[]) is called before the page is evaluated. Then, Initiator.doAfterCompose(org.zkoss.zk.ui.Page) is called after all components are created, and before any event is processed. In additions, Initiator.doFinally() is called after the page has been evaluated. If an exception occurs, Initiator.doCatch(java.lang.Throwable) is called.

A typical usage: starting a transaction in doInit, rolling back it in Initiator.doCatch(java.lang.Throwable) and commit it in Initiator.doFinally() (if Initiator.doCatch(java.lang.Throwable) is not called).

Author:

Ian Tsai

Constructor Summary

InitTag()

Method Summary

void	doTag() Add this Initiator into HttpRequest, this will be processed by Component container: PageTag.
java.lang.String	getUse() Returns the class that implements Initiator.
void	setDynamicAttribute(java.lang.String uri, java.lang.String localName, java.lang.Object value) Called when a tag declared to accept dynamic attributes is passed an attribute that is not declared in the Tag Library Descriptor.
void	setUse(java.lang.String clazz) Sets the class that implements Initiator.

Methods inherited from class org.zkoss.jsp.zul.impl.AbstractTag

getIf, getUnless, isEffective, setIf, setUnless

Methods inherited from class javax.servlet.jsp.tagext.SimpleTagSupport

findAncestorWithClass, getJspBody, getJspContext, getParent, setJspBody, setJspContext, setParent

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

InitTag

public InitTag()

Method Detail

setDynamicAttribute

public void setDynamicAttribute(java.lang.String uri,
                                java.lang.String localName,
                                java.lang.Object value)
                         throws javax.servlet.jsp.JspException

Called when a tag declared to accept dynamic attributes is passed an attribute that is not declared in the Tag Library Descriptor.
In this InitTag implementation, this method is used to "add" args.
For Example:

<z:init use="demo.MyInit" arg0="an arg" arg1="another arg " ...../>

Specified by:

setDynamicAttribute in interface javax.servlet.jsp.tagext.DynamicAttributes

Parameters:

uri - the namespace of the attribute. Ignored in this version.

localName - the name of the attribute being set.

value - the value of the attribute

Throws:

javax.servlet.jsp.JspException

doTag

public void doTag()
           throws javax.servlet.jsp.JspException,
                  java.io.IOException

Add this Initiator into HttpRequest, this will be processed by Component container: PageTag.

Specified by:

doTag in interface javax.servlet.jsp.tagext.SimpleTag

Overrides:

doTag in class javax.servlet.jsp.tagext.SimpleTagSupport

Throws:

javax.servlet.jsp.JspException

java.io.IOException

setUse

public void setUse(java.lang.String clazz)

Sets the class that implements Initiator.

Parameters:

clazz - a class name with derived class which is implements Initiator

Throws:

java.lang.IllegalArgumentException - if input class can't be found or is not implement Initiator

getUse

public java.lang.String getUse()

Returns the class that implements Initiator.