001 // Copyright 2011, 2012 The Apache Software Foundation
002 //
003 // Licensed under the Apache License, Version 2.0 (the "License");
004 // you may not use this file except in compliance with the License.
005 // You may obtain a copy of the License at
006 //
007 // http://www.apache.org/licenses/LICENSE-2.0
008 //
009 // Unless required by applicable law or agreed to in writing, software
010 // distributed under the License is distributed on an "AS IS" BASIS,
011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012 // See the License for the specific language governing permissions and
013 // limitations under the License.
014
015 package org.apache.tapestry5.alerts;
016
017 import org.apache.tapestry5.OptimizedSessionPersistedObject;
018 import org.apache.tapestry5.ioc.internal.util.CollectionFactory;
019 import org.apache.tapestry5.ioc.internal.util.LockSupport;
020
021 import java.io.Serializable;
022 import java.util.Iterator;
023 import java.util.List;
024
025 /**
026 * A stateless session object used to store Alerts between requests.
027 *
028 * @since 5.3
029 */
030 public class AlertStorage extends LockSupport implements Serializable, OptimizedSessionPersistedObject
031 {
032 private boolean dirty;
033
034 private final List<Alert> alerts = CollectionFactory.newList();
035
036 @Override
037 public boolean checkAndResetDirtyMarker()
038 {
039 try
040 {
041 takeWriteLock();
042
043 return dirty;
044 } finally
045 {
046 dirty = false;
047
048 releaseWriteLock();
049 }
050 }
051
052
053 public void add(Alert alert)
054 {
055 assert alert != null;
056
057 try
058 {
059 takeWriteLock();
060
061 alerts.add(alert);
062
063 dirty = true;
064 } finally
065 {
066 releaseWriteLock();
067 }
068 }
069
070 /**
071 * Dismisses all Alerts.
072 */
073 public void dismissAll()
074 {
075 try
076 {
077 takeWriteLock();
078
079 if (!alerts.isEmpty())
080 {
081 alerts.clear();
082 dirty = true;
083 }
084 } finally
085 {
086 releaseWriteLock();
087 }
088 }
089
090 /**
091 * Dismisses non-persistent Alerts; this is useful after rendering the {@link org.apache.tapestry5.corelib.components.Alerts}
092 * component.
093 */
094 public void dismissNonPersistent()
095 {
096 try
097 {
098 takeWriteLock();
099
100 Iterator<Alert> i = alerts.iterator();
101
102 while (i.hasNext())
103 {
104 if (!i.next().duration.persistent)
105 {
106 dirty = true;
107 i.remove();
108 }
109 }
110 } finally
111 {
112 releaseWriteLock();
113 }
114 }
115
116
117 /**
118 * Dismisses a single Alert, if present.
119 */
120 public void dismiss(long alertId)
121 {
122 try
123 {
124 takeWriteLock();
125
126 Iterator<Alert> i = alerts.iterator();
127
128 while (i.hasNext())
129 {
130 if (i.next().id == alertId)
131 {
132 i.remove();
133 dirty = true;
134 return;
135 }
136 }
137 } finally
138 {
139 releaseWriteLock();
140 }
141 }
142
143
144 /**
145 * Returns all stored alerts.
146 *
147 * @return list of alerts (possibly empty)
148 */
149 public List<Alert> getAlerts()
150 {
151 try
152 {
153 acquireReadLock();
154
155 return alerts;
156 } finally
157 {
158 releaseReadLock();
159 }
160 }
161 }