hibernate second level ehcache miss
I'm trying to get a second-level hibernate cache working, using the ehcache implementation.
I'm sure it's some obvious noob mistake I'm making, but I can't see what it is!
To test out my cache, I'm doing the following:
Creating an object and saving it. I 'get' it once within the transaction, where I can see I get the object back without a db hit, which is just the hibernate first level cache doing its thing.
Then I commit the transaction and start a new session.
This time, when I 'get' the object, I can see a cache miss from ehcache in the debugs. I would have expected the object to be in the cache now since I saved it in the previous transaction?
Here's my code:
Session session = getSession();
session.beginTransaction();
开发者_开发问答Test1 test1a = new Test1();
test1a.setId(5);
test1a.setName("Test 1");
test1a.setValue(10);
// Touch it
session.save(test1a);
// Now get it
Test1 test1b = (Test1)session.get(Test1.class, 5);
// Within a transaction, the session caches it - no db hit
System.out.println("GOT object with value "+test1b.getValue());
session.getTransaction().commit();
System.out.println("Between sessions");
session = getSession();
session.beginTransaction();
test1b = (Test1)session.get(Test1.class, 5);
System.out.println("GOT object with value "+test1b.getValue());
session.getTransaction().commit();
And here's the relevant part of my hibernate.cfg.xml
<property name="cache.provider_class">org.hibernate.cache.EhCacheProvider</property>
And my ehcache.xml
<?xml version="1.0" encoding="UTF-8"?>
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="http://ehcache.sf.net/ehcache.xsd">
<cache name="com.play.hibernate1.Test1" maxElementsInMemory="1000" eternal="false" timeToLiveSeconds="600" overflowToDisk="false"/>
<defaultCache maxElementsInMemory="10000" eternal="false"
overflowToDisk="true" timeToIdleSeconds="10" timeToLiveSeconds="20" diskPersistent="true" />
</ehcache>
And my annotations
@Entity
@Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
public class Test1 {
And the debug logs
11:21:03,474 DEBUG CacheManager:239 - Configuring ehcache from classpath. 11:21:03,479 DEBUG ConfigurationFactory:122 - Configuring ehcache from ehcache.xml found in the classpath: file:/Users/bw/Documents/workspace/hibernate1/target/classes/ehcache.xml 11:21:03,479 DEBUG ConfigurationFactory:87 - Configuring ehcache from URL: file:/Users/brucewood/Documents/workspace/hibernate1/target/classes/ehcache.xml 11:21:03,480 DEBUG ConfigurationFactory:139 - Configuring ehcache from InputStream 11:21:03,485 DEBUG BeanHandler:213 - Ignoring ehcache attribute xmlns:xsi 11:21:03,485 DEBUG BeanHandler:213 - Ignoring ehcache attribute xsi:noNamespaceSchemaLocation 11:21:03,517 DEBUG ConfigurationHelper:208 - No CacheManagerEventListenerFactory class specified. Skipping... 11:21:03,518 DEBUG ConfigurationHelper:183 - No CachePeerListenerFactoryConfiguration specified. Not configuring a CacheManagerPeerListener. 11:21:03,518 DEBUG ConfigurationHelper:159 - No CachePeerProviderFactoryConfiguration specified. Not configuring a CacheManagerPeerProvider. 11:21:03,525 DEBUG ConfigurationHelper:135 - No BootstrapCacheLoaderFactory class specified. Skipping... 11:21:03,526 DEBUG ConfigurationHelper:135 - No BootstrapCacheLoaderFactory class specified. Skipping... 11:21:03,532 DEBUG MemoryStore:73 - Initialized net.sf.ehcache.store.LruMemoryStore for com.play.hibernate1.Test1 11:21:03,533 DEBUG LruMemoryStore:71 - com.play.hibernate1.Test1 Cache: Using SpoolingLinkedHashMap implementation 11:21:03,533 DEBUG Cache:429 - Initialised cache: com.play.hibernate1.Test1 1528 [Finalizer] INFO org.hibernate.connection.DriverManagerConnectionProvider - cleaning up connection pool: jdbc:mysql://localhost:3306/play 1668 [main] INFO org.hibernate.impl.SessionFactoryObjectFactory - Not binding factory to JNDI, no JNDI name configured GOT object with value 10 Hibernate: /* insert com.play.hibernate1.Test1 */ insert into Test1 (name, value, id) values (?, ?, ?) 1274984463818|1|1|batch|/* insert com.play.hibernate1.Test1 */ insert into Test1 (name, value, id) values (?, ?, ?)|/* insert com.play.hibernate1.Test1 */ insert into Test1 (name, value, id) values ('Test 1', 10, 5) 1274984463820|1|1|statement|/* insert com.play.hibernate1.Test1 */ insert into Test1 (name, value, id) values (?, ?, ?)|/* insert com.play.hibernate1.Test1 */ insert into Test1 (name, value, id) values ('Test 1', 10, 5) 1274984463821|1|1|commit|| Between sessions 11:21:03,823 DEBUG EhCache:68 - key: com.play.hibernate1.Test1#5 11:21:03,823 DEBUG MemoryStore:138 - com.play.hibernate1.Test1Cache: com.play.hibernate1.Test1MemoryStore miss for com.play.hibernate1.Test1#5 11:21:03,823 DEBUG Cache:661 - com.play.hibernate1.Test1 cache - Miss 11:21:03,824 DEBUG EhCache:77 - Element for com.play.hibernate1.Test1#5 is null Hibernate: /* load com.play.hibernate1.Test1 */ select test1x0_.id as id0_0_, test1x0_.name as name0_0_, test1x0_.value as value0_0_ from Test1 test1x0_ where test1x0_.id=? 1274984463829|4|1|statement|/* load com.play.hibernate1.Test1 */ select test1x0_.id as id0_0_, test1x0_.name as name0_0_, test1x0_.value as value0_0_ from Test1 test1x0_ where test1x0_.id=?|/* load com.play.hibernate1.Test1 */ select test1x0_.id as id0_0_, test1x0_.name as name0_0_, test1x0_.value as value0_0_ from Test1 test1x0_ where test1x0_.id=5 1274984463831|-1||resultset|/* load com.play.hibernate1.Test1 */ select test1x0_.id as id0_0_, test1x0_.name as name0_0_, test1x0_.value as value0_0_ from Test1 test1x0_ where test1x0_.id=5|name0_0_ = Test 1, value0_0_ = 10 GOT object with value 10 1274984463834|0|1|commit||
Thanks for your help!
The problem was that I was using NONSTRICT_READ_WRITE. It seemed to fit the bill from this explanation in the docs:
If the application only occasionally needs to update data (i.e. if it is extremely unlikely that two transactions would try to update the same item simultaneously), and strict transaction isolation is not required, a nonstrict-read-write cache might be appropriate. If the cache is used in a JTA environment, you must specify hibernate.transaction.manager_lookup_class. In other environments, you should ensure that the transaction is completed when Session.close() or Session.disconnect() is called.
but actually it looks like it doesn't add saved objects to the cache.. Docs are a little thin here, IMO. There is a better treatment of the caching options in Java Persistence with Hibernate, although still a little thin on concrete explanation of what actually happens to your data. Anyway..
I changed my caching option to READ_WRITE, and now it works as expected.
Note also that the first time an object gets added to the cache, you get a 'cache miss' in the ehcache debugs. Presumably it looks in its cache, finds the object is not there, records a miss, then adds the object. After that, you get 'hits'.
Also be wary of the bug in org.hibernate.action.internal.BulkOperationCleanupAction.#affectedEntity see discussion in both
https://forum.hibernate.org/viewtopic.php?f=1&t=998970
and
https://hibernate.atlassian.net/browse/HHH-4035
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