nesteddefinetag.java

structs源码

/*
 * $Id: NestedDefineTag.java 471754 2006-11-06 14:55:09Z husted $
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.struts.taglib.nested.bean;

import org.apache.struts.taglib.bean.DefineTag;
import org.apache.struts.taglib.nested.NestedNameSupport;
import org.apache.struts.taglib.nested.NestedPropertyHelper;

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

/**
 * NestedDefineTag.
 *
 * @version $Rev: 471754 $ $Date: 2004-10-16 12:38:42 -0400 (Sat, 16 Oct 2004)
 *          $
 * @since Struts 1.1
 */
public class NestedDefineTag extends DefineTag implements NestedNameSupport {
    /* the usual private member variables */
    private String originalName = null;
    private String originalProperty = null;

    /**
     * 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 {
        // get the original properties
        originalName = getName();
        originalProperty = getProperty();

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

        // set the properties
        NestedPropertyHelper.setNestedProperties(request, this);

        // let the super do it's thing
        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(originalName);
        setProperty(originalProperty);

        // continue
        return i;
    }

    /**
     * Release the tag's resources and reset the values.
     */
    public void release() {
        super.release();

        // reset the originals
        originalName = null;
        originalProperty = null;
    }
}