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1 package org.jboss.hibernate.cache;
2
3 import java.util.HashMap  ;
4 import java.util.Iterator ;
5 import java.util.Map ;
6 import java.util.Set ;
7
8 import javax.transaction.SystemException ;
9 import javax.transaction.Transaction ;
10 import javax.transaction.TransactionManager ;
11
12 import org.hibernate.cache.Cache;
13 import org.hibernate.cache.CacheException;
14 import org.jboss.cache.Fqn;
15 import org.jboss.cache.InvocationContext;
16 import org.jboss.cache.Node;
17 import org.jboss.cache.config.Option;
18 import org.jboss.cache.lock.TimeoutException;
19 import org.jboss.logging.Logger;
20
21
27 public class JBCCache implements Cache
28 {
29
30 private static final Logger log = Logger.getLogger(JBCCache.class);
31
32 private static final String ITEM = "item";
33
34 private org.jboss.cache.Cache cache;
35 private final String regionName;
36 private final Fqn regionFqn;
37 private final TransactionManager transactionManager;
38
39 public JBCCache(org.jboss.cache.Cache cache, String regionName, TransactionManager transactionManager)
40 throws CacheException {
41 this.cache = cache;
42 this.regionName = regionName;
43 this.regionFqn = Fqn.fromString( regionName.replace( '.', '/' ) );
44 this.transactionManager = transactionManager;
45 }
46
47 public Object get(Object key) throws CacheException {
48 Transaction tx = suspend();
49 try {
50 return read(key);
51 }
52 finally {
53 resume( tx );
54 }
55 }
56
57 public Object read(Object key) throws CacheException {
58 try {
59 return cache.get( new Fqn( regionFqn, key ), ITEM );
60 }
61 catch (Exception e) {
62 throw new CacheException(e);
63 }
64 }
65
66 public void update(Object key, Object value) throws CacheException {
67 try {
68 cache.put( new Fqn( regionFqn, key ), ITEM, value );
69 }
70 catch (Exception e) {
71 throw new CacheException(e);
72 }
73 }
74
75 public void put(Object key, Object value) throws CacheException {
76 Transaction tx = suspend();
77 try {
78 cache.putForExternalRead(new Fqn( regionFqn, key ), ITEM, value);
80 }
81 catch (TimeoutException te) {
82 log.debug("ignoring write lock acquisition failure");
84 }
85 catch (Exception e) {
86 throw new CacheException(e);
87 }
88 finally {
89 resume( tx );
90 }
91 }
92
93 private void resume(Transaction tx) {
94 try {
95 if (tx!=null) transactionManager.resume(tx);
96 }
97 catch (Exception e) {
98 throw new CacheException("Could not resume transaction", e);
99 }
100 }
101
102 private Transaction suspend() {
103 Transaction tx = null;
104 try {
105 if ( transactionManager!=null ) {
106 tx = transactionManager.suspend();
107 }
108 }
109 catch (SystemException se) {
110 throw new CacheException("Could not suspend transaction", se);
111 }
112 return tx;
113 }
114
115 public void remove(Object key) throws CacheException {
116 try {
117 cache.remove( new Fqn( regionFqn, key ) );
118 }
119 catch (Exception e) {
120 throw new CacheException(e);
121 }
122 }
123
124 public void clear() throws CacheException {
125 try {
126 cache.remove( regionFqn );
127 }
128 catch (Exception e) {
129 throw new CacheException(e);
130 }
131 }
132
133 public void destroy() throws CacheException {
134 try {
135 InvocationContext ctx = cache.getInvocationContext();
143 Option opt = new Option();
144 opt.setCacheModeLocal(true);
145 ctx.setOptionOverrides(opt);
146 cache.removeNode( regionFqn );
147 }
148 catch( Exception e ) {
149 throw new CacheException( e );
150 }
151 }
152
153 public void lock(Object key) throws CacheException {
154 throw new UnsupportedOperationException ( "TreeCache is a fully transactional cache" + regionName );
155 }
156
157 public void unlock(Object key) throws CacheException {
158 throw new UnsupportedOperationException ( "TreeCache is a fully transactional cache: " + regionName );
159 }
160
161 public long nextTimestamp() {
162 return System.currentTimeMillis() / 100;
163 }
164
165 public int getTimeout() {
166 return 600; }
168
169 public String getRegionName() {
170 return regionName;
171 }
172
173 public long getSizeInMemory() {
174 return -1;
175 }
176
177 public long getElementCountInMemory() {
178 try {
179 Set children = getChildrenNames();
180 return children == null ? 0 : children.size();
181 }
182 catch (Exception e) {
183 throw new CacheException(e);
184 }
185 }
186
187 public long getElementCountOnDisk() {
188 return 0;
189 }
190
191 public Map toMap() {
192 try {
193 Map result = new HashMap ();
194 Set childrenNames = getChildrenNames();
195 if (childrenNames != null) {
196 Iterator iter = childrenNames.iterator();
197 while ( iter.hasNext() ) {
198 Object key = iter.next();
199 result.put(
200 key,
201 cache.get( new Fqn( regionFqn, key ), ITEM )
202 );
203 }
204 }
205 return result;
206 }
207 catch (Exception e) {
208 throw new CacheException(e);
209 }
210 }
211
212 private Set getChildrenNames()
213 {
214 try {
215 Node base = cache.getChild( regionFqn );
216 return (base == null ? null : base.getChildrenNames());
217 }
218 catch (Exception e) {
219 throw new CacheException(e);
220 }
221 }
222
223 public String toString() {
224 return "JBCCache(" + regionName + ')';
225 }
226 }
227 |
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