Java tutorial
/* This file is part of Cyclos (www.cyclos.org). A project of the Social Trade Organisation (www.socialtrade.org). Cyclos 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. Cyclos 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. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Cyclos; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ package nl.strohalm.cyclos.taglibs; import java.io.IOException; import javax.servlet.http.HttpServletRequest; import javax.servlet.jsp.JspException; import javax.servlet.jsp.tagext.TagSupport; import org.apache.commons.lang.StringUtils; /** * Renders a script tag, appending the cyclos version as a parameter to avoid browser cache between versions * @author luis */ public class ScriptTag extends TagSupport { private static final long serialVersionUID = 5044196774749124533L; private String src; @Override public int doEndTag() throws JspException { src = StringUtils.trimToNull(src); if (src != null) { try { pageContext.getOut().println(generateScriptTag()); } catch (final IOException e) { throw new JspException(e); } finally { release(); } } return EVAL_PAGE; } public String generateScriptTag() { final StringBuilder sb = new StringBuilder(); final HttpServletRequest request = (HttpServletRequest) pageContext.getRequest(); final String fullPath = request.getContextPath() + src; final Object version = pageContext.getServletContext().getAttribute("cyclosVersion"); sb.append("<script language=\"javascript\" src=\"").append(fullPath).append("?version=").append(version) .append("\"></script>"); return sb.toString(); } public String getSrc() { return src; } @Override public void release() { super.release(); src = null; } public void setSrc(final String src) { this.src = src; } }