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1
22 package org.jboss.ejb;
23
24 import java.util.HashMap  ;
25
26 import org.jboss.monitor.EntityLockMonitor;
27 import org.jboss.monitor.LockMonitor;
28 import org.jboss.logging.Logger;
29 import javax.naming.InitialContext ;
30
31
40 public class BeanLockManager
41 {
42 private static final int NUMBER_OF_INSTANCES=40;
43 private static Logger log = Logger.getLogger(BeanLockManager.class);
44
45
47 private HashMap map[] = new HashMap [NUMBER_OF_INSTANCES];
48
49
50
51 private Container container;
52
53
54 private boolean reentrant = false;
55 private int txTimeout = 5000;
56
57 private boolean trace;
58 public Class lockClass;
59 protected LockMonitor monitor = null;
60
61 private BeanLockManager()
62 {
63 for (int i=0;i<map.length;i++)
64 {
65 map[i] = new HashMap ();
66 }
67 }
68 public BeanLockManager(Container container)
69 {
70 this();
71 this.container = container;
72 trace = log.isTraceEnabled();
73 try
74 {
75 InitialContext ctx = new InitialContext ();
76 EntityLockMonitor elm = (EntityLockMonitor) ctx.lookup(EntityLockMonitor.JNDI_NAME);
77 String jndiName = container.getBeanMetaData().getContainerObjectNameJndiName();
78 monitor = elm.getEntityLockMonitor(jndiName);
79 }
80 catch (Exception ignored)
81 {
82 }
84 }
85
86 public LockMonitor getLockMonitor()
87 {
88 return monitor;
89 }
90
91 private HashMap getHashMap(Object id)
92 {
93 final int mapInUse = id.hashCode()%NUMBER_OF_INSTANCES;
94 if (mapInUse>0)
95 {
96 return map[mapInUse];
97 }
98 else
99 {
100 return map[mapInUse*-1];
101 }
102 }
103
104
112 public BeanLock getLock(Object id)
113 {
114 if (id == null)
115 throw new IllegalArgumentException ("Attempt to get lock ref with a null object");
116
117 HashMap mapInUse = getHashMap(id);
118
119 synchronized (mapInUse)
120 {
121 BeanLock lock = (BeanLock) mapInUse.get(id);
122 if (lock!=null)
123 {
124 lock.addRef();
125 return lock;
126 }
127 }
128
129 try
130 {
131 BeanLock lock2 = (BeanLock)createLock(id);
132 synchronized(mapInUse)
133 {
134 BeanLock lock = (BeanLock) mapInUse.get(id);
135 if (lock != null)
137 {
138 lock.addRef();
139 return lock;
140 }
141 mapInUse.put(id, lock2);
142 lock2.addRef();
143 return lock2;
144 }
145 }
146 catch (Exception e)
147 {
148 log.warn("Failed to initialize lock:"+id, e);
151 throw new RuntimeException (e);
152 }
153 }
154
155 private BeanLock createLock(Object id) throws Exception
156 {
157 BeanLock lock = (BeanLock) lockClass.newInstance();
158 lock.setId(id);
159 lock.setTimeout(txTimeout);
160 lock.setContainer(container);
161
162 return lock;
163 }
164
165 public void removeLockRef(Object id)
166 {
167 if (id == null)
168 throw new IllegalArgumentException ("Attempt to remove lock ref with a null object");
169
170 HashMap mapInUse = getHashMap(id);
171
172 synchronized(mapInUse)
173 {
174 BeanLock lock = (BeanLock) mapInUse.get(id);
175
176 if (lock != null)
177 {
178 try
179 {
180 lock.removeRef();
181 if( trace )
182 log.trace("Remove ref lock:"+lock);
183 }
184 finally
185 {
186 if (lock.getRefs() <= 0)
191 {
192 Object mapLock = mapInUse.remove(lock.getId());
193 if( trace )
194 log.trace("Lock no longer referenced, lock: "+lock);
195 }
196 }
197 }
198 }
199 }
200
201 public boolean canPassivate(Object id)
202 {
203 if (id == null)
204 throw new IllegalArgumentException ("Attempt to passivate with a null object");
205
206 HashMap mapInUse = getHashMap(id);
207 synchronized (mapInUse)
208 {
209 BeanLock lock = (BeanLock) mapInUse.get(id);
210 if (lock == null)
211 throw new IllegalStateException ("Attempt to passivate without a lock");
212
213 return (lock.getRefs() <= 1);
214 }
215 }
216
217 public void setLockCLass(Class lockClass)
218 {
219 this.lockClass = lockClass;
220 }
221
222 public void setReentrant(boolean reentrant)
223 {
224 this.reentrant = reentrant;
225 }
226
227 public void setContainer(Container container)
228 {
229 this.container = container;
230 }
231 }
232 |
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