package com.hwlcn.security.web.tags; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.servlet.jsp.JspException; public class UserTag extends SecureTag { private static final Logger log = LoggerFactory.getLogger(UserTag.class); public int onDoStartTag() throws JspException { if (getSubject() != null && getSubject().getPrincipal() != null) { if (log.isTraceEnabled()) { log.trace("Subject has known identity (aka 'principal'). " + "Tag body will be evaluated."); } return EVAL_BODY_INCLUDE; } else { if (log.isTraceEnabled()) { log.trace("Subject does not exist or have a known identity (aka 'principal'). " + "Tag body will not be evaluated."); } return SKIP_BODY; } } }