1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.shiro.web.tags;
20
21 import javax.servlet.jsp.JspException;
22
23 import org.slf4j.Logger;
24 import org.slf4j.LoggerFactory;
25
26
27 /**
28 * JSP tag that renders the tag body if the current user known to the system, either from a successful login attempt
29 * (not necessarily during the current session) or from 'RememberMe' services.
30 *
31 * <p><b>Note:</b> This is <em>less</em> restrictive than the <code>AuthenticatedTag</code> since it only assumes
32 * the user is who they say they are, either via a current session login <em>or</em> via Remember Me services, which
33 * makes no guarantee the user is who they say they are. The <code>AuthenticatedTag</code> however
34 * guarantees that the current user has logged in <em>during their current session</em>, proving they really are
35 * who they say they are.
36 *
37 * <p>The logically opposite tag of this one is the {@link org.apache.shiro.web.tags.GuestTag}.
38 *
39 * @since 0.9
40 */
41 public class UserTag extends SecureTag {
42
43 //TODO - complete JavaDoc
44
45 private static final Logger log = LoggerFactory.getLogger(UserTag.class);
46
47 public int onDoStartTag() throws JspException {
48 if (getSubject() != null && getSubject().getPrincipal() != null) {
49 if (log.isTraceEnabled()) {
50 log.trace("Subject has known identity (aka 'principal'). " +
51 "Tag body will be evaluated.");
52 }
53 return EVAL_BODY_INCLUDE;
54 } else {
55 if (log.isTraceEnabled()) {
56 log.trace("Subject does not exist or have a known identity (aka 'principal'). " +
57 "Tag body will not be evaluated.");
58 }
59 return SKIP_BODY;
60 }
61 }
62
63 }