imagetag.java

structs源码

/*
 * $Id: ImageTag.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.html;

import org.apache.struts.Globals;
import org.apache.struts.config.ModuleConfig;
import org.apache.struts.taglib.TagUtils;
import org.apache.struts.util.ModuleUtils;

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

/**
 * Tag for input fields of type "image".
 *
 * @version $Rev: 471754 $ $Date: 2005-04-26 20:11:47 -0400 (Tue, 26 Apr 2005)
 *          $
 */
public class ImageTag extends SubmitTag {
    // ------------------------------------------------------------- Properties

    /**
     * The alignment for this image.
     */
    protected String align = null;

    /**
     * The border size around the image.
     */
    protected String border = null;

    /**
     * The module-relative URI of the image.
     */
    protected String page = null;

    /**
     * The message resources key of the module-relative URI of the image.
     */
    protected String pageKey = null;

    /**
     * The URL of this image.
     */
    protected String src = null;

    /**
     * The message resources key for the URL of this image.
     */
    protected String srcKey = null;

    /**
     * The module prefix (beginning with a slash) which will be used to find
     * the action for this link.
     */
    protected String module = null;

    // --------------------------------------------------------- Constructor
    public ImageTag() {
        super();
        property = "";
    }

    /**
     * @deprecated Align attribute is deprecated in HTML 4.x.
     */
    public String getAlign() {
        return (this.align);
    }

    /**
     * @deprecated Align attribute is deprecated in HTML 4.x.
     */
    public void setAlign(String align) {
        this.align = align;
    }

    public String getBorder() {
        return (this.border);
    }

    public void setBorder(String border) {
        this.border = border;
    }

    public String getPage() {
        return (this.page);
    }

    public void setPage(String page) {
        this.page = page;
    }

    public String getPageKey() {
        return (this.pageKey);
    }

    public void setPageKey(String pageKey) {
        this.pageKey = pageKey;
    }

    public String getSrc() {
        return (this.src);
    }

    public void setSrc(String src) {
        this.src = src;
    }

    public String getSrcKey() {
        return (this.srcKey);
    }

    public void setSrcKey(String srcKey) {
        this.srcKey = srcKey;
    }

    public String getModule() {
        return (this.module);
    }

    public void setModule(String module) {
        this.module = module;
    }

    // --------------------------------------------------------- Protected Methods

    /**
     * Render the opening element.
     *
     * @return The opening part of the element.
     */
    protected String getElementOpen() {
        return "<input type=\"image\"";
    }

    /**
     * Render the button attributes
     *
     * @param results The StringBuffer that output will be appended to.
     */
    protected void prepareButtonAttributes(StringBuffer results)
        throws JspException {
        String tmp = src();

        if (tmp != null) {
            HttpServletResponse response =
                (HttpServletResponse) pageContext.getResponse();

            prepareAttribute(results, "src", response.encodeURL(tmp));
        }

        prepareAttribute(results, "align", getAlign());
        prepareAttribute(results, "border", getBorder());
        prepareAttribute(results, "value", getValue());
        prepareAttribute(results, "accesskey", getAccesskey());
        prepareAttribute(results, "tabindex", getTabindex());
    }

    /**
     * Release any acquired resources.
     */
    public void release() {
        super.release();
        page = null;
        pageKey = null;
        property = "";
        src = null;
        srcKey = null;
    }

    // ------------------------------------------------------ Protected Methods

    /**
     * Return the base source URL that will be rendered in the
     * <code>src</code> property for this generated element, or
     * <code>null</code> if there is no such URL.
     *
     * @throws JspException if an error occurs
     */
    protected String src() throws JspException {
        // Deal with a direct context-relative page that has been specified
        if (this.page != null) {
            if ((this.src != null) || (this.srcKey != null)
                || (this.pageKey != null)) {
                JspException e =
                    new JspException(messages.getMessage("imgTag.src"));

                TagUtils.getInstance().saveException(pageContext, e);
                throw e;
            }

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

            ModuleConfig config =
                ModuleUtils.getInstance().getModuleConfig(this.module,
                    request, pageContext.getServletContext());

            String pageValue = this.page;

            if (config != null) {
                pageValue =
                    TagUtils.getInstance().pageURL(request, this.page, config);
            }

            return (request.getContextPath() + pageValue);
        }

        // Deal with an indirect context-relative page that has been specified
        if (this.pageKey != null) {
            if ((this.src != null) || (this.srcKey != null)) {
                JspException e =
                    new JspException(messages.getMessage("imgTag.src"));

                TagUtils.getInstance().saveException(pageContext, e);
                throw e;
            }

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

            ModuleConfig config =
                ModuleUtils.getInstance().getModuleConfig(this.module,
                    request, pageContext.getServletContext());

            String pageValue =
                TagUtils.getInstance().message(pageContext, getBundle(),
                    getLocale(), this.pageKey);

            if (config != null) {
                pageValue =
                    TagUtils.getInstance().pageURL(request, pageValue, config);
            }

            return (request.getContextPath() + pageValue);
        }

        // Deal with an absolute source that has been specified
        if (this.src != null) {
            if (this.srcKey != null) {
                JspException e =
                    new JspException(messages.getMessage("imgTag.src"));

                TagUtils.getInstance().saveException(pageContext, e);
                throw e;
            }

            return (this.src);
        }

        // Deal with an indirect source that has been specified
        if (this.srcKey == null) {
            JspException e =
                new JspException(messages.getMessage("imgTag.src"));

            TagUtils.getInstance().saveException(pageContext, e);
            throw e;
        }

        return TagUtils.getInstance().message(pageContext, getBundle(),
            getLocale(), this.srcKey);
    }
}