/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package javax.servlet.jsp.tagext;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.PageContext;
/**
* Tags are Java classes implementing JSP Tag extensions. The class must
* have a null argument public constructor and implement the tag attribute
* as setXXX methods, following the Beans spec.
*
* <pre><code>
* MyTag tag = new MyTag();
*
* tag.setPageContext(page);
* tag.setParent(...);
* tag.setFoo(...);
* tag.setBar(...);
* if (tag.doStartTag() == EVAL_BODY_INCLUDE) {
* ...
* }
* if (tag.doEndTag() == SKIP_PAGE)
* return;
* ...
* tag.setParent(...);
* tag.setFoo(...);
* if (tag.doStartTag() == EVAL_BODY_INCLUDE) {
* ...
* }
* if (tag.doEndTag() == SKIP_PAGE)
* return;
* ...
* tag.release();
* </code><pre>
*/
public interface Tag extends JspTag {
public final static int SKIP_BODY = 0;
public final static int EVAL_BODY_INCLUDE = 1;
public final static int SKIP_PAGE = 5;
public final static int EVAL_PAGE = 6;
/**
* Sets the page context of this page.
*/
public void setPageContext(PageContext page);
/**
* Sets the containing tag.
*/
public void setParent(Tag t);
/**
* Returns the containing tag.
*/
public Tag getParent();
/**
* Callback to handle the start of a tag.
*
* <p>doStartTag can assume <code>setPageContext</code>,
* <code>setParent</code>, and all tag attribute properties have
* been called.
*
* @return SKIP_BODY to ignore the body and EVAL_BODY_INCLUDE
* to evaluate the body.
*/
public int doStartTag() throws JspException;
/**
* Callback to handle the end of a tag.
* @return SKIP_PAGE to skip the rest of the page and
* EVAL_PAGE to continue with the rest of the page.
*/
public int doEndTag() throws JspException;
/**
* Cleans up the tag at the end of the page. The same tag instance
* might be reused for multiple tags in the page.
*/
public void release();
}