I need help with lazy blob loading in Hibernate.
I have in my web application these servers and frameworks: MySQL, Tomcat, Spring and Hibernate.
The part of database config.
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
<property name="user" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
<property name="driverClass" value="${jdbc.driverClassName}"/>
<property name="jdbcUrl" value="${jdbc.url}"/>
<property name="initialPoolSize">
<value>${jdbc.initialPoolSize}</value>
</property>
<property name="minPoolSize">
<value>${jdbc.minPoolSize}</value>
</property>
<property name="maxPoolSize">
<value>${jdbc.maxPoolSize}</value>
</property>
<property name="acquireRetryAttempts">
<value>${jdbc.acquireRetryAttempts}</value>
</property>
<property name="acquireIncrement">
<value>${jdbc.acquireIncrement}</value>
</property>
<property name="idleConnectionTestPeriod">
<value>${jdbc.idleConnectionTestPeriod}</value>
</property>
<property name="maxIdleTime">
<value>${jdbc.maxIdleTime}</value>
</property>
<property name="maxConnectionAge">
<value>${jdbc.maxConnectionAge}</value>
</property>
<property name="preferredTestQuery">
<value>${jdbc.preferredTestQuery}</value>
</property>
<property name="testConnectionOnCheckin">
<value>${jdbc.testConnectionOnCheckin}</value>
</property>
</bean>
<bean id="lobHandler" class="org.springframework.jdbc.support.lob.DefaultLobHandler" />
<bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="configLocation" value="/WEB-INF/hibernate.cfg.xml" />
<property name="configurationClass" value="org.hibernate.cfg.AnnotationConfiguration" />
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">${hibernate.dialect}</prop>
</props>
</property>
<property name="lobHandler" ref="lobHandler" />
</bean>
<tx:annotation-driven transaction-manager="txManager" />
<bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
The part of entity class
#Lob
#Basic(fetch=FetchType.LAZY)
#Column(name = "BlobField", columnDefinition = "LONGBLOB")
#Type(type = "org.springframework.orm.hibernate3.support.BlobByteArrayType")
private byte[] blobField;
The problem description. I'm trying to display on a web page database records related to files, which was saved in MySQL database. All works fine if a volume of data is small. But the volume of data is big I'm recieving an error java.lang.OutOfMemoryError: Java heap space
I've tried to write in blobFields null values on each row of table. In this case, application works fine, memory doesn't go out of. I have a conclusion that the blob field which is marked as lazy (#Basic(fetch=FetchType.LAZY)) isn't lazy, actually!
I'm confused. Emmanuel Bernard wrote in ANN-418 that #Lob are lazy by default (i.e. you don't even need to use the #Basic(fetch = FetchType.LAZY) annotation).
Some users report that lazy loading of a #Lob doesn't work with all drivers/database.
Some users report that it works when using bytecode instrumentation (javassit? cglib?).
But I can't find any clear reference of all this in the documentation.
At the end, the recommended workaround is to use a "fake" one-to-one mappings instead of properties. Remove the LOB fields from your existing class, create new classes referring to the same table, same primary key, and only the necessary LOB fields as properties. Specify the mappings as one-to-one, fetch="select", lazy="true". So long as your parent object is still in your session, you should get exactly what you want. (just transpose this to annotations).
I would suggest you to use inheritance to handle this scenario. Have a base class without the blob and a derived class containing the byte array. You would use the derived class only when you need to display the blob on the UI.
Of course you could extract that value and put it into a new table with a "#OneToOne" relation that is lazy, however in our application the LOBs are loaded lazily on demand using just this configuration
#Lob
#Fetch(FetchMode.SELECT)
#Type(type="org.hibernate.type.PrimitiveByteArrayBlobType")
byte[] myBlob;
This is tested in our project simultaneously on PostgreSQL, MySQL, SQLServer and Oracle, so it should work for u
Lazy property loading requires buildtime bytecode instrumentation.
Hibernate docs: Using lazy property fetching
If you want to avoid bytecode instrumentation one option is to to create two entities that use same table, one with the blob one without. Then only use the entity with blob when you need the blob.
I had the same issue and this was my fix:
My Entity:
#Entity
#Table(name = "file")
public class FileEntity {
#Id
#GeneratedValue
private UUID id;
#NotNull
private String filename;
#NotNull
#Lob #Basic(fetch = FetchType.LAZY)
private byte[] content;
...
Added plugin to pom.xml:
<plugin>
<groupId>org.hibernate.orm.tooling</groupId>
<artifactId>hibernate-enhance-maven-plugin</artifactId>
<executions>
<execution>
<phase>compile</phase>
<configuration>
<failOnError>true</failOnError>
<enableLazyInitialization>true</enableLazyInitialization>
</configuration>
<goals>
<goal>enhance</goal>
</goals>
</execution>
</executions>
</plugin>
For me lazy load only worked by compiling and then running it, didn't work on eclipse or intellij for example.
I'm using gradle then I did the following to get it working
Annotate entity
Setup Hibernate gradle plugin
build.gradle
buildscript {
repositories {
mavenCentral()
}
dependencies {
classpath "org.hibernate:hibernate-gradle-plugin:5.4.0.Final"
}
}
apply plugin: 'java'
apply plugin: 'application'
apply plugin: 'org.hibernate.orm'
hibernate {
enhance {
enableLazyInitialization = true
enableDirtyTracking = true
enableAssociationManagement = true
}
}
Entity.java
#Entity
public class Person {
#Id
#GeneratedValue
private Integer id;
#Lob
#Basic(fetch = FetchType.LAZY)
#Column(length = 255, nullable = false)
private String name;
Testing
./gradlew run
Full working example
Lazy loading works for me if I use Blob type instead of byte[].
#Column(name = "BlobField", nullable = false)
#Lob
#Basic(fetch = FetchType.LAZY)
private Blob blobField;
This one gets lazily loaded and if you need to retrieve its value access this field:
String value = IOUtils.toByteArray(entity.getBlobField().getBinaryStream());
A simple workarround using #OneTone notation based on the response of #MohammadReza Alagheband (Why does #Basic(fetch=lazy) doesn't work in my case?) but without the requirement of create a new table for each required lazy attribute is the following:
#Getter
#Setter
#Entity
#Table(name = "document")
#AllArgsConstructor
#NoArgsConstructor
public class DocumentBody implements java.io.Serializable{
#Column(name = "id", insertable = false)
#ReadOnlyProperty
#Id
#PrimaryKeyJoinColumn
private Integer id;
#Column(name = "body", unique = true, nullable = false, length = 254)
#JsonView({JSONViews.Simple.class, JSONViews.Complete.class})
private String content;
}
#Getter
#Entity
#Setter
#Table(name = "document")
#AllArgsConstructor
#NoArgsConstructor
public class DocumentTitle implements java.io.Serializable{
#Column(name = "id", insertable = false)
#ReadOnlyProperty
#Id
private Integer id;
#Column(name = "title", unique = true, nullable = false, length = 254)
#JsonView({JSONViews.Simple.class, JSONViews.Complete.class})
private String content;
}
public class Document implements java.io.Serializable {
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "id", unique = true, nullable = false)
#JsonView({JSONViews.Simple.class, JSONViews.Complete.class})
private Integer id;
//Also it is posssible to prove with #ManyToOne
#OneToOne(fetch = FetchType.LAZY, optional = false, cascade = {CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH})
#JoinColumn(name = "id", referencedColumnName = "id", nullable = false)
#JsonView({JSONViews.Simple.class, JSONViews.Complete.class})
private DocumentTitle title;
#OneToOne(fetch = FetchType.LAZY, optional = false, cascade = {CascadeType.MERGE, CascadeType.PERSIST, CascadeType.REFRESH})
#JoinColumn(name = "id", referencedColumnName = "id", nullable = false)
#JsonView({JSONViews.Simple.class, JSONViews.Complete.class})
private DocumentBody body;
}
Related
I am using Hibernate 4 orm and search for my twitter application. The problem is when I start persisting tweets into MariaDB table, id (primary key) gets incremented by five fold:
2
7
12
17
22
27
I tried all Generation Types which are available : SEQUENCE, IDENTITY, TABLE and AUTO. But none of this provided increment by one. I guess I am missing some configuration, otherwise it should provide increment by one.
Here is my Entity class and hibernate.cfg.xml file:
#Entity
#Indexed
#Table(name="tweets_table")
public class TweetPOJO implements Serializable{
private static final long serialVersionUID = 1123211L;
#Id
#GeneratedValue (???)
#Column(name = "raw_id" )
private int raw_id;
#Column(name = "tweet_id")
private String tweet_id;
#DateBridge(resolution=Resolution.DAY)
#Column(name = "posted_time")
private String timestamp;
#Field(index = Index.YES, analyze = Analyze.YES, store = Store.NO)
#Column(name = "cleaned_text")
private String tweet_text;
#Column(name = "hashtags")
#Field(index=Index.YES, analyze=Analyze.NO, store=Store.YES)
private String hashtags;
#Column(name = "media_url")
private String media_url;
#Column(name = "media_text")
private String media_text;
#Column(name = "media_type")
private String media_type;
#Column(name = "location")
private String location;
...
...
public void setUser_frind_count(int user_frind_count) {
this.user_frind_count = user_frind_count;
}
#Override
public String toString() {
return tweet_id+" : "+tweet_text;
}
}
Here is hibernate.cfg.xml
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration SYSTEM "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.bytecode.use_reflection_optimizer"> true </property>
<property name="hibernate.dialect"> org.hibernate.dialect.MySQLDialect </property>
<property name="hibernate.connection.driver_class"> com.mysql.jdbc.Driver </property>
<!-- Assume test is the database name -->
<property name="hibernate.connection.url"> jdbc:mysql://*******/clouddata </property>
<property name="hibernate.connection.username"> root </property>
<property name="hibernate.connection.password"> qwe123 </property>
<property name="connection.pool_size"> 1 </property>
<property name="hibernate.search.default.directory_provider"> filesystem </property>
<property name="hibernate.search.default.indexBase"> E:\lucene_index </property>
<!--
whether the schema will be created or just updated, every time the sessionFactory is created.
This is configured in the hibernate.hbm2ddl.auto property, which is set to update. So the schema
is only updated. If this property is set to create, then every time we run our application, the
schema will be re-created, thus deleting previous data.
-->
<property name="hibernate.hbm2ddl.auto">update</property>
<mapping class="twitter_crawling_modul.TweetPOJO"/>
</session-factory>
You can try to use sequence generator
#SequenceGenerator(name = "seq", sequenceName = "seq_name", allocationSize = 1)
#GeneratedValue (strategy = GenerationType.SEQUENCE, generator = "seq")
My problem is that hibernate retrieve null in the value of the #OneToMany Set organizationMemberCollection when fetching an instance on the following object :
UserAccount.java :
#Entity
#Table(name="USER_ACCOUNT")
public class UserAccount {
#Id
#Column(name = "id", nullable = false)
#SequenceGenerator(name = "generator", sequenceName = "USER_ACCOUNT_id_seq", allocationSize=1)
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "generator")
private Long id;
#Column(name = "EMAIL", nullable = false)
private String email;
#Column(name = "PASSWORD_HASH")
private String passwordHash;
#OneToMany(fetch = FetchType.LAZY, mappedBy = "userAccount")
private Set <OrganizationMember> organizationMemberCollection;
...
/*
* getters and setters
*/
}
Here is the Object that "owns" the association :
OrganizationMember.java :
#Entity
#Table(name="ORGANIZATION_MEMBER")
public class OrganizationMember{
#Id
#Column(name = "id", nullable = false)
#SequenceGenerator(name = "generator", sequenceName = "ORGANIZATION_MEMBER_id_seq", allocationSize=1)
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "generator")
private Long id;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "USER_ACCOUNT_ID", nullable = false)
private UserAccount userAccount;
...
/*
* getters and setters
*/
}
In this application we have two different configuations :
Production, where Hibernate is connected to a PostgreSQL database.
Here is the sessionFactory configuration for prod :
<bean id="sessionFactory"
class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">
<property name="hibernateProperties">
<props>
<prop key="hibernate.jdbc.batch_size">10</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.cglib.use_reflection_optimizer">false</prop>
</props>
</property>
...
</bean>
Test, where Hibernate is conencted to an in memory HSQLDB database :
<bean id="sessionFactory"
class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.HSQLDialect</prop>
<prop key="hibernate.show_sql">false</prop>
<prop key="hibernate.cglib.use_reflection_optimizer">false</prop>
<prop key="hibernate.hbm2ddl.auto">create-drop</prop>
<prop key="hibernate.cache.use_second_level_cache">false</prop>
<prop key="hibernate.cache.use_query_cache">false</prop>
</props>
</property>
...
</bean>
This issue only show up in testing configuration; In production configuration everything's going nicely and I can get the collection.
However, when I fetch an UserAccount in the test configuration I get null in the organizationMemberCollection property (Not an empty Set).
After some hours of research through google and Hibernate's doc I still haven't found any post relating to the same issue/behaviour, so I'm a lillte bit lost and help would be greatly appreciated !
I can of course provide more information if needed, Thanks !
Edit :
Test higlighting the problem :
#Test
#Transactional
public void testFindUserAccount_OrganizationMemberCollectionFetching() {
assertNotNull(userAccountDao.findUserAccount("user1#test.fr")); //NoProblem
assertNotNull(userAccountDao.findUserAccount("user1#test.fr").getCabinetMemberCollection()); //Fails
}
With the following findUserAccount dao
public UserAccount findUserAccount(String email) {
if (email == null) {
return null;
}
UserAccount userAccount = (UserAccount) this.sessionFactory
.getCurrentSession().createCriteria(UserAccount.class)
.add(Restrictions.eq("email", email).ignoreCase())
.uniqueResult();
if (userAccount == null) {
throw new ObjectNotFoundException("UserAccount.notFound");
} else {
return userAccount;
}
}
The issue was that the database population and the test were running in the same transaction, and hibernate cache wasn't cleaned between these two steps.
The consequence was that hibernate didn't really fired the request to the database, but hit the cache instead and returned the object without doing any join with the mapped relation.
The possible solutions are :
Populate the database in a different Transaction.
Clean the Session SessionFactory.getCurrentSession().clean(); after the population. (Flush the session before if needed : SessionFactory.getCurrentSession().flush();).
Each possibility will force the next query to really hit the database, therefore the join will occur and the mapped Collection will contain the wanted data (or be empty if the join has no result, but in any case the Collection won't have the null value).
In my opinin the first solution is way better as it doesn't rollback the whole population if something goes wrong in the test.
It's a lazy loaded collection, so hibernate doesn't do anything to initialize it, quite normal that hibernate returns null here ..
What I usually do is declare an empty HashSet on the property :
#OneToMany(fetch = FetchType.LAZY, mappedBy = "userAccount")
private Set <OrganizationMember> organizationMemberCollection = new hashSet<>();
In my case it was because I had "transient" as the entity was not serializable an Sonar told me to add the transient keyword
#OneToMany(mappedBy = "message", cascade = CascadeType.REMOVE, orphanRemoval = true, fetch = FetchType.LAZY)
private transient List<UserReadSystemMessage> usersRead;
Note the transient
I am trying to make a relationship between 2 entities in different jar.
This is a first entity which is in main project:
#Entity(name = "StdyDtlLabelBean")
#Table(name = "STDY_DTL_LABEL")
public class StdyDtlLabelBean implements Serializable {
#EmbeddedId
private StdyDtlLabelBeanPk id;
#ManyToOne(targetEntity = StdyDtlSubject.class)
#JoinColumns({
#JoinColumn(name="STUDY_ID", insertable = false, updatable = false, referencedColumnName="STUDY_ID"),
#JoinColumn(name="SUBJECT_ID", insertable = false, updatable = false, referencedColumnName="SUBJECT_ID")
})
private StdyDtlSubject subject;
//getters and setters
}
This one is an entity which is in library project as a jar file:
#Entity
#Table(name = "STDY_DTL_SUBJECT")
public class StdyDtlSubject implements Serializable {
private static final long serialVersionUID = 2479124604L;
public StdyDtlSubject() {
}
#EmbeddedId
private StdyDtlSubjectPK key;
//getters and setters
}
#Embeddable
public class StdyDtlSubjectPK implements Serializable {
private static final long serialVersionUID = 6691432687933341920L;
#Column(name = "STUDY_ID")
private Integer studyId;
#Column(name = "SUBJECT_ID")
private String subjectId;
public StdyDtlSubjectPK() {
}
Here is the persistence unit:
<persistence-unit name="stdyPersistence" transaction-type="RESOURCE_LOCAL">
<jta-data-source>java:comp/env/jdbc/OraclePooledDS</jta-data-source>
<class>com.ctasc.ctpm.jpa.StdyDtlSubject</class>
<class>stdy.brms.beans.StdyDtlLabelBean</class>
<properties>
<property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect" />
<property name="hibernate.show_sql" value="true" />
<property name="hibernate.format_sql" value="true" />
</properties>
</persistence-unit>
When I create an entity manager factory I gets following error:
#OneToOne or #ManyToOne on stdy.brms.beans.StdyDtlLabelBean.subject references an unknown entity: com.ctasc.ctpm.jpa.StdyDtlSubject
But if I remove a relationship annotation from StdyDtlLabelBean entity and create named queries on StdyDtlSubject entity. Those named queries work fine. Also, if I copy StdyDtlSubject class to my main project, it works fine. I gets this error only if I put relationship between them.
I've tried adding
<jar-file>ctpm.jar</jar-file>
<jar-file>lib/ctpm.jar</jar-file>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<property name="hibernate.archive.autodetection" value="class, hbm" />
<property name="packagesToScan" value="com.ctasc.ctpm.jpa" />
None of them helped me to solve this. Could you please suggest something to solve this problem?
Ensure that the jar which you want to relate to has a persisence.xml in it's META-INF with all entities in the jar enlisted.
I am using EclipseLink JPA as ORM and web logic 10.3 as an application server in my project. Everything working fine until i got a bug for data refresh. Here is the case one of my entity table row is updated to new value but my entity manager or JPA did not pick that value. For this we have lite rely re started the server. then it picked up the value.
Here is my persistence.xml file and here is the way i am using entity manager in my class.
<persistence-unit name="BasePersistenceUnit" transaction-type="JTA">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>jdbc/CTH_DS</jta-data-source>
<class>org.test.partyrequest.model.dataobject.RqstTrc</class>
<exclude-unlisted-classes>true</exclude-unlisted-classes>
<properties>
<property name="eclipselink.target-server" value="WebLogic_10" />
<!-- Logging level is set to INFO, Need to change in Production -->
<property name="eclipselink.logging.level" value="FINE" />
<property name="eclipselink.persistence-context.flush-mode" value="COMMIT" />
<property name="eclipselink.persistence-context.close-on-commit" value="true" />
<property name="eclipselink.cache.shared.default" value="false" />
</properties>
</persistence-unit>
SPRING JPA XML FILE
<context:load-time-weaver aspectj-weaving="on" />
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="persistenceUnitName" value="BasePersistenceUnit" />
</bean>
<bean id="jpaVendorAdapter" class="org.springframework.orm.jpa.vendor.EclipseLinkJpaVendorAdapter" />
<bean id="transactionManager" class="org.springframework.transaction.jta.WebLogicJtaTransactionManager" />
<!-- ========================= BUSINESS OBJECT DEFINITIONS ========================= -->
<!-- Instruct Spring to perform declarative transaction management automatically on annotated classes. -->
<tx:annotation-driven mode="aspectj" transaction-manager="transactionManager"/>
<!-- Post-processor to perform exception translation on #Repository classes
(from native exceptions such as JPA PersistenceExceptions to Spring's DataAccessException hierarchy).
-->
<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />
My Entity calss
#Entity
#Table(name = "PRTY_RQST")
public class PrtyRqst implements Serializable {
private static final long serialVersionUID = -4679712398918736694L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "PRTY_RQST_PRTYRQSTID_GENERATOR")
#SequenceGenerator(name = "PRTY_RQST_PRTYRQSTID_GENERATOR", allocationSize = 1, sequenceName = "PRTY_RQST_SEQ")
#Column(name = "PRTY_RQST_ID")
private Long prtyRqstId;
#Column(name = "CHLD_RQST_IND")
private String chldRqstInd;
#Column(name = "PARNT_PRTY_RQST_ID")
private BigDecimal parntPrtyRqstId;
#Column(name = "PROCES_REFR")
private String procesRefr;
#Temporal(TemporalType.TIMESTAMP)
#Column(name = "RQST_DT_TM")
private Date rqstDtTm;
#Column(name = "UPDT_BY")
private String updtBy;
// bi-directional many-to-one association to PrtyKey
#OneToMany(mappedBy = "prtyRqst", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
private List<PrtyKey> prtyKeys;
// bi-directional many-to-one association to PrtyRqstHist
#OneToMany(mappedBy = "prtyRqst", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
#OrderBy("rqstDtTm DESC")
private List<PrtyRqstHist> prtyRqstHists;
#OneToOne(mappedBy = "prtyRqst", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
private RqstPayload rqstPayload;
// bi-directional many-to-one association to RqstTrc
#OneToMany(mappedBy = "prtyRqst", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
private List<RqstTrc> rqstTrcs;
// bi-directional many-to-one association to AddtnRqstInfo
#OneToMany(mappedBy = "prtyRqst", fetch = FetchType.LAZY, cascade = CascadeType.ALL)
private List<AddtnRqstInfo> addtnRqstInfos;
// bi-directional many-to-one association to BusnApplc
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.REFRESH)
#JoinColumn(name = "BUSN_APPLC_ID")
private BusnApplc busnApplc;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.REFRESH)
#JoinColumn(name = "INTN_PROCES_TYP_ID")
private IntnProcesTyp intnProcesTyp;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.REFRESH)
#JoinColumn(name = "INTN_STATS_ID")
private IntnStat intnStat;
#Column(name = "ORCHESTRATION_ID")
private String orchestrationId;
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.REFRESH)
#JoinColumn(name = "ALLW_CHNL_ID")
private AllwChnl allwChnl;
// bi-directional many-to-one association to RqstTyp
#ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.REFRESH)
#JoinColumn(name = "RQST_TYP_ID")
private RqstTyp rqstTyp;
#Column(name = "TRACK_RQST_IND")
private String trackRqstInd;
#Temporal(TemporalType.TIMESTAMP)
#Column(name = "SUBMIT_DT_TM")
private Date submitDtTm;
#Temporal(TemporalType.DATE)
#Column(name = "EFFECTIVE_DT")
private Date effectiveDt;
#Temporal(TemporalType.TIMESTAMP)
#Column(name = "RQST_CREATE_DT_TM")
private Date rqstCreateDtTm;
In my DAO IMPL class I have this.persist(prtyRqstDO);
#Transactional(readOnly = true, propagation=Propagation.REQUIRED)
private PartyRequestBO createRequest(PartyRequestBO partyRequestBO, boolean isParent) throws RuntimeException {
if (log.isDebugEnabled()) {
log.debug("Enter: PartyRequestsDAOImpl:createRequest()");
}
partyRequestBO.setOrchestrationID(generateOrchestrationId());
PrtyRqst prtyRqstDO = PartyRequestEntityMapper.partyRequestMapper(partyRequestBO, isParent, true);
try {
this.persist(prtyRqstDO);
partyRequestBO.setRequestIdentifier(prtyRqstDO.getPrtyRqstId());
} catch (Exception e) {
if(log.isDebugEnabled()) {
log.debug("PartyRequestsDAOImpl:createRequest : " + PartyRequestConstants.UNABLE_TO_INSERT, e);
}
throw new PartyRequestDataException(PartyRequestConstants.UNABLE_TO_INSERT, e);
}
if (log.isDebugEnabled()) {
log.debug("Exit: PartyRequestsDAOImpl:createRequest()");
}
return partyRequestBO;
}
#Transactional(readOnly = true, propagation=Propagation.REQUIRED)
public void persist(T entity) {
if (log.isDebugEnabled()) {
log.debug("Enter: BaseDAO:persist() : " + entity);
}
this.getEntityManager().persist(entity);
if (log.isDebugEnabled()) {
log.debug("Exit: BaseDAO:persist()");
}
}
public EntityManager getEntityManager() {
if (log.isDebugEnabled()) {
log.debug("Enter: BaseDAO:getEntityManager() : " + this.entityManager);
}
return this.entityManager;
}
Here the problem is, if i update the row in one of the table through back end my application container is not picking the change.
Can any one Tell me? thank you in advance.
EDIT:
Thank you both of you. I have modified according to your comments added following lines of code.
this.entityManager.clear();
this.entityManager.close();
//this.getEntityManager().refresh(entityManager);
Here i could able to get the update value what i have done it through backend with out restarting server. But the problem is it hold all the changed values.
for example i have changed value to FulOrderWSA it was working. changed to FulorderWSB it was working again.Now i have tried for FulOrderWSZ it didn't work(DB values is FulorderWSB ).
Finally i tried here with old value that is FulorderWSA as per DB it should not work but it worked for me. what i noticed that it is holding all the DB changed values here.
How to get ride of this. I have used both clear and close for entityManager. can any one help me on this.
thank you.
Vijay.
You have turned off the EclipseLink shared cache (AKA second level cache), so the issue is likely that you are holding onto long lived EntityManagers. Once an entity becomes managed by the EM, JPA requires that EM to return that exact instance from every find/query operation as it was when first read and any changes your app might have made to it.
There are a number of options. The best is to look at your EntityManager lifecycle and only obtain an EntityManager when needed, and close it when done. Or, just call em.clear() at points to prevent them from filling up, which will detach all entities associated to the em. Make sure to flush changes though if you wish to keep the changes before calling clear.
If there is a specific entity you need to refresh, em.refresh(entity) will work. This will clear any changes the application might have made though, and can be dangerous with cascade refresh settings mixed with lazy access - so use carefully or you may unintentionally wipe out changes to a whole tree at a later time.
You have caching disabled, so you should see any database changes.
My guess is that you are hold onto a single EntityManager in your DAO. This is very bad, as an EntityManger should be created per transaction, or per request, not held for the duration of the application. It is also not thread safe, so holding onto a single one does not make sense, as it is a transactional object.
You seem to also be using Spring, so it might be proxying the EntityManager underneath and creating one per transaction, but perhaps you have not configured Spring or your transactions correctly.
Include the code the creating/configures the EntityManager.
Thanks,
for all your support. Basically we are not using Cache from EclipseLink. we had bean that handles all the metadata initialization as init method. what we have done is, used JDK Timer to reload the particular Bean to refresh the data. It was working fine.
I have checked the time taking to refresh the all the methods are less than 500 milliseconds. I can foresee only issue when this thread is executing and there is a request.since it is taking less than 500 millisecs its ok for us.
I hope this will be helpful if someone is not using cache you can try this approach.
Thank you.
I have a problem with lazy initialisation. I can't find a solution.
Exception:
[pool-1-thread-12] ERROR:12:20:14.840 o.h.LazyInitializationException - failed to lazily initialize a collection of role: de.beeld.forges.domain.Server.applications, no session or session was closed
org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: de.beeld.forges.domain.Server.applications, no session or session was closed
at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:380)
at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:372)
[pool-2-thread-1] ERROR:12:20:14.840 o.s.s.support.MethodInvokingRunnable - Invocation of method 'readStatusCache' on target class [class de.beeld.forges.task.annotation.ScheduledProcessor$$EnhancerByCGLIB$$ee649dc3] failed
java.util.ConcurrentModificationException: null
at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372)
at java.util.AbstractList$Itr.next(AbstractList.java:343)
hibernate.xml
<!-- Hibernate SessionFactory -->
<bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"
p:dataSource-ref="standardDataSource" p:lobHandler-ref="defaultLobHandler">
<property name="annotatedClasses">
<list>
<value>de.beeld.forges.domain.Server</value>
<value>de.beeld.forges.domain.Application</value>
<value>de.beeld.forges.domain.Forge</value>
</list>
</property>
</property>
</bean>
<bean id="defaultLobHandler" class="org.springframework.jdbc.support.lob.DefaultLobHandler" />
<!-- Read in DAOs from the hibernate package -->
<context:component-scan base-package="de.beeld.forges.dao" />
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager"
p:sessionFactory-ref="sessionFactory" />
<bean id="transactionTemplate"
class="org.springframework.transaction.support.TransactionTemplate">
<property name="transactionManager" ref="transactionManager" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />
<context:component-scan base-package="de.beeld">
<context:exclude-filter expression="org.springframework.stereotype.Controller"
type="annotation" />
<context:exclude-filter expression="org.springframework.stereotype.Repository"
type="annotation" />
</context:component-scan>
<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />
readStatusCache method:
public void readStatusCache() {
String execCommand = "java -jar ...";
List<Future<Map<Long, Integer>>> list = new ArrayList<Future<Map<Long, Integer>>>();
String serverName = null;
for (Server server : serviceFacade.getServers()) {
serverName = server.getName();
Callable<Map<Long, Integer>> worker = new ApplicationStatusReader2(server.getApplications(),
sshConnector, execCommand, serverName);
Future<Map<Long, Integer>> submit = this.serviceFacade.getExecutor().submit(worker);
list.add(submit);
}
for (Future<Map<Long, Integer>> future : list) {
//do stuff
}
}
Server.java
#Entity
#org.hibernate.annotations.Entity(dynamicUpdate = true)
public class Server implements DomainObject, Comparable<Server> {
private static final long serialVersionUID = -8920952435734596243L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Column(unique = true, nullable = false)
#NotEmpty
private String name;
#Column(nullable = false)
#NotEmpty
#Pattern(regexp = "^([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])$", message = "The ip must be in format xxx.xxx.xxx.xxx")
private String ip;
#Column(nullable = false)
#NotEmpty
private String fqdn;
#OneToMany(mappedBy = "server", fetch = FetchType.LAZY)
private List<Application> applications;
#Version
private int version;
//getter and setter
}
Application.java
#Entity
public class Application implements DomainObject {
private static final long serialVersionUID = -8127137156319959239L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#ManyToOne(fetch = FetchType.LAZY)
private Server server;
#Column(nullable = false)
#NotEmpty
private String name;
#Column(nullable = false)
#NotEmpty
private String location;
#Column(nullable = false)
#NotEmpty
private String binDir;
private String confDir;
private boolean isContainer = false;
private String containerDir;
private String startup = "startup.sh";
private String shutdown = "shutdown.sh";
#ManyToOne(fetch = FetchType.LAZY)
#Fetch(FetchMode.JOIN)
private Forge forge;
#ManyToOne(fetch = FetchType.LAZY)
#Fetch(FetchMode.JOIN)
private Application parent;
#OneToMany(mappedBy = "parent", fetch = FetchType.LAZY)
private List<Application> offsprings;
#NotEmpty
private String blueprint;
private Integer replaceable = 0;
private Integer running = 0;
#Version
private int version;
//getter and setter
}
I don't really know why I cant read the list of applications from the server
If anybody could help it would be great.
Most likely because you're setting applications collection to lazy load. So when you return from the initial call to serviceFacade.getServers(), my guess is that you no longer have the session opened that was used to fetch the list of servers.
As a result, when you iterator through the applications, the session was closed, so it can't load the actual contents of the collection.
You have three possibilities:
Keep the session open (google for binding hibernate session to thread, or if the readStatusCache method is in a spring managed object, just add an #Transactional annotation to it, or the entry point from which it is called).
Change the applications collection to be an eager load
have your dao layer fully initialize the applications collection (see Hibernate.initialize method) while the session is still open.
The two loops
for (Server server : serviceFacade.getServers()) {
serverName = server.getName();
Callable<Map<Long, Integer>> worker = new ApplicationStatusReader2(server.getApplications(),
sshConnector, execCommand, serverName);
Future<Map<Long, Integer>> submit = this.serviceFacade.getExecutor().submit(worker);
list.add(submit);
}
for (Future<Map<Long, Integer>> future : list) {
//do stuff
}
are being called by two separate threads simultaneously. You can check if this is the case by synchronizing the readStatusCache() method. But this should be done in the Spring layer. Are you using transactions etc. properly?
Please read this answer for more on thread safety with spring and hibernate. Spring-Hibernate used in a webapp,what are strategies for Thread safe session management
When I got the same exception, the solution was to add the #Transactional annotation to the method in the controller.