nestedlinktag.java

这是一个轻便的j2ee的web应用框架,是一个在多个项目中运用的实际框架,采用struts,hebinate,xml等技术,有丰富的tag,role,navigation,session,dictio

/*
 * $Header: /sfroot/cvs/esimple/src/core/com/esimple/framework/web/taglib/nested/html/NestedLinkTag.java,v 1.1.1.1 2004/09/08 06:38:23 lava Exp $
 * $Revision: 1.1.1.1 $
 * $Date: 2004/09/08 06:38:23 $
 * ====================================================================
 *
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Struts", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact [e-mail].
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
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 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */
package com.esimple.framework.web.taglib.nested.html;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.JspException;

import com.esimple.framework.web.taglib.html.LinkTag;
import com.esimple.framework.web.taglib.nested.NestedNameSupport;
import com.esimple.framework.web.taglib.nested.NestedPropertyHelper;

/**
 * NestedLinkTag.
 * @author Arron Bates
 * @since Struts 1.1
 * @version $Revision: 1.1.1.1 $ $Date: 2004/09/08 06:38:23 $
 */
public class NestedLinkTag extends LinkTag implements NestedNameSupport {

  /**
   * Overriding method of the heart of the matter. Gets the relative property
   * and leaves the rest up to the original tag implementation. Sweet.
   * @return int JSP continuation directive.
   *             This is in the hands of the super class.
   */
  public int doStartTag() throws JspException {
    origName = super.getName();
    origProperty = super.getProperty();
    origParamProperty = super.getParamProperty();

    /* decide the incoming options. Always two there are */
    boolean doProperty = (origProperty != null && origProperty.length() > 0);
    boolean doParam = (origParamProperty != null && origParamProperty.length() > 0);

    // request
    HttpServletRequest request = (HttpServletRequest)pageContext.getRequest();

    boolean hasName = (getName() != null && getName().trim().length() > 0);
    String currentName;
    if (hasName) {
      currentName = getName();
    } else {
      currentName = NestedPropertyHelper.getCurrentName(request, this);
    }
    // set the bean name
    super.setName(currentName);

    // set property details
    if (doProperty && !hasName) {
      super.setProperty(NestedPropertyHelper.getAdjustedProperty(request, origProperty));
    }
    // do the param property details
    if (doParam) {
      super.setName(null);
      super.setParamName(currentName);
      super.setParamProperty(NestedPropertyHelper.getAdjustedProperty(request, origParamProperty));
    }
    
    /* do the tag */
    return super.doStartTag();
  }

  /**
   * Complete the processing of the tag. The nested tags here will restore
   * all the original value for the tag itself and the nesting context.
   * @return int to describe the next step for the JSP processor
   * @throws JspException for the bad things JSP's do
   */
  public int doEndTag() throws JspException {
    // do the super's ending part
    int i = super.doEndTag();

    // reset the properties
    setName(origName);
    setProperty(origProperty);
    setParamProperty(origParamProperty);

    // continue
    return i;
  }

  /**
   * Release the tag's resources and reset the values.
   */
  public void release() {
    super.release();
    // reset the originals
    origName = null;
    origProperty = null;
    origParamProperty = null;
  }


  /* hold original property */
  private String origName = null;
  private String origProperty = null;
  private String origParamProperty = null;
}