I have this in my pom.xml for ENHANCMENT and works: <!--OPENJPA ENHANCMENT--> <plugin> <groupId>org.apache.openjpa</groupId> <artifactId>openjpa-maven-plugin</artifactId> <version>2.2.0</version> <configuration> <includes>mypackage/model/*.class</includes> <addDefaultConstructor>true</addDefaultConstructor>
<enforcePropertyRestrictions>true</enforcePropertyRestrictions> <connectionDriverName>com.mysql.jdbc.Driver</connectionDriverName> <connectionProperties> driverClass=${database.driver.name}, jdbcUrl=${database.connection.url}, user=${database.user}, password=${database.password}, minPoolSize=5, acquireRetryAttempts=3, maxPoolSize=20 </connectionProperties> </configuration> <executions> <execution> <id>enhancer</id> <phase>process-classes</phase> <goals> <goal>enhance</goal> </goals> </execution> </executions> <dependencies> <dependency> <groupId>org.apache.openjpa</groupId> <artifactId>openjpa</artifactId> <version>2.2.0</version> </dependency> </dependencies> </plugin> In my persistence.xml i have: <property name="openjpa.ConnectionUserName" value="${db.username}"/> <property name="openjpa.ConnectionPassword" value="${db.password}"/> <property name="openjpa.ConnectionURL" value="${db.url}"/> <property name="openjpa.ConnectionDriverName" value="${db.driver.class}"/> You can replace the database properties in persistence.xml with your own values (${db.username},${db.password},${db.url},${db.driver.class}). I use this configuration for my JEE Projects. Maybe this can help you. Regards. SCJA. JL Cetina 2012/11/18 Chris Wolf <cwolf.a...@gmail.com> > I wrote a shell script to directly invoke PCEnhancer on class > java.util.HashSet, > and even that didn't work: > > $ ./enhance.sh > 52 openjpa INFO [main] openjpa.Tool - Enhancer running on type > "java.util.HashSet". > Exception in thread "main" java.lang.RuntimeException: > java.io.FileNotFoundExcep > tion: file:\C:\opt\jdk\jre\lib\rt.jar!\java\util\HashSet.class (The > filename, directory name, or volume label syntax is incorrect) > at > org.apache.openjpa.lib.conf.Configurations.launchRunnable(Configurations.java:744) > > On Sun, Nov 18, 2012 at 10:37 AM, Chris Wolf <cwolf.a...@gmail.com> wrote: > > Hello, > > > > This is my first posting and first attempt to use OpenJPA. I put > > together a quick demo and can persist > > individual, unrelated entities. However, when I try to persist > > related entities to two tables via a link table, i.e. many-2-many, > > it keeps complaining about "casting to PersistenceCapable", in > > particular the class "java.util.HashSet". > > > > First, I am using the Eclipse JPA plugin (called "Dali" or > > "EclipseLink"). Of course, I have OpenJPA configured > > as my JPA provider, I am in a plain Java SE environment with > > LOCAL_RESOURCE via JDBC connection > > properties in the persistence.xml. I am using Sun/Oracle 64bit > > JDK-1.6 and OpenJPA-2.2.0. > > > > I am using the Eclipse JPA plugin to generate the entity classes from > > already-exiting database schema objects, > > and that code looks like (just pasting the relationship code), this > > action also adds these classes to persistence.xml > > via persistence-unit/class elements. > > > > First M2M entity, "MarketData": > > > > //bi-directional many-to-many association to RiskFactor > > @ManyToMany(mappedBy="marketData") > > public Set<RiskFactor> getRiskFactors() { > > return this.riskFactors; > > } > > > > Second M2M entity "RiskFactor": > > > > //bi-directional many-to-many association to MarketData > > @ManyToMany > > @JoinTable( > > name="MARKET_DATA__RISK_FACTOR" > > , joinColumns={ > > @JoinColumn(name="RISK_FACTOR_ID", > nullable=false) > > } > > , inverseJoinColumns={ > > @JoinColumn(name="MARKET_DATA_ID", > nullable=false) > > } > > ) > > public Set<MarketData> getMarketData() { > > return this.marketData; > > } > > > > When I run the code, the log indicates implicit runtime enhacement, > > yet it is complaining: > > > > "[persistdemo.ojpa.entities.RiskFactor@61578aab] [java.util.HashSet]" > > to PersistenceCapable failed. Ensure that it has been enhanced." > > > > ...when it says, "Ensure that it has been enhanced." - which is "it" > > referring to? The entity "RiskFactor" or the field relationship > > field's class, "java.util.HashSet"? > > > > > > 186 openjpa INFO [main] openjpa.Runtime - OpenJPA dynamically > > loaded the class enhancer. Any classes that were not enhanced at build > > time will be enhanced when they are loaded by the JVM. > > SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder". > > SLF4J: Defaulting to no-operation (NOP) logger implementation > > SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for > > further details. > > 243 openjpa INFO [main] openjpa.Runtime - OpenJPA dynamically > > loaded a validation provider. > > 596 openjpa INFO [main] openjpa.Runtime - Starting OpenJPA 2.2.0 > > 630 openjpa INFO [main] openjpa.jdbc.JDBC - Using dictionary class > > "org.apache.openjpa.jdbc.sql.OracleDictionary". > > Exception in thread "main" <openjpa-2.2.0-r422266:1244990 nonfatal > > user error> org.apache.openjpa.persistence.ArgumentException: Attempt > > to cast instance "[persistdemo.ojpa.entities.RiskFactor@61578aab] > > [java.util.HashSet]" to PersistenceCapable failed. Ensure that it has > > been enhanced. > > > > Maybe because "java.util.HashSet" was loaded before the dynamic > > enhancer could get to it? > > > > Next, I tried performing build-time enhancement via Maven, per this doc: > > http://openjpa.apache.org/enhancement-with-maven.html > > > > When I ran "mvn openjpa:enhance", it finished with success, but none > > of the classes in target/classes seemed to have be changed > > (last-modified date same as compile-time). and re-running results in > > the same error and stack-trace. > > > > My openjpa:enhance configuration was: > > <configuration> > > <includes>**/entities/*.class,java.util.HashSet</includes> > > <addDefaultConstructor>true</addDefaultConstructor> > > <enforcePropertyRestrictions>true</enforcePropertyRestrictions> > > </configuration> > > > > > > Next, I tried invoking with: > > > > -javaagent:/opt/apache-openjpa-2.2.0/openjpa-all-2.2.0.jar > > > > Same error - same stack trace. > > > > Then, I tried setting this property: > > openjpa.RuntimeUnenhancedClasses=supported > > > > Same error - same stack trace. > > > > > > Then, following a suggestion I found here: > > > http://openjpa.208410.n2.nabble.com/JPA-adding-entities-to-EntityManagerFactory-programmatically-td210697.html > > > > I tried setting both: > > openjpa.RuntimeUnenhancedClasses=supported > > openjpa.MetaDataFactory=jpa(Types=java.util.HashSet) > > > > BTW, this is a dead link > > "User's Guide on Enhancement" / > > > http://openjpa.apache.org/builds/latest/docs/manual/manual.html#ref_guide_pc_enhance > > (from page: http://openjpa.apache.org/entity-enhancement.html) > > > > So is there any way to use OpenJPA to persist objects related via a > > link table? (there obviously must be, > > but it's a total mystery to me) I can't believe it's this difficult, > > I must be doing something really dumb. > > > > Regards, > > > > CW > -- ------------------------------------------------------------------- *SCJA. José Luis Cetina* -------------------------------------------------------------------