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H2 database console: how to connect to an embedded H2 JPA database?

I have a couple of unit tests for an application's JPA layer. This JPA layer consists in JPA entities and a service providing the basic API required in order to persist the entities. The unit tets directly use the javax.persistence classes in order to handle the PersistenceManager. Then it tests the persistence API and I can see in the log the SQL statements to create tables and sequences, etc.
The relevant part of the persistence.xml file looks like:
<persistence-unit name="..." transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
...
<properties>
<property name="javax.persistence.jdbc.url" value="jdbc:h2:mem:test"/>
<property name="javax.persistence.jdbc.driver" value="org.h2.Driver"/>
<property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
<property name="hibernate.hbm2ddl.auto" value="create-drop"/>
<property name="hibernate.format_sql" value="false"/>
<property name="hibernate.show_sql" value="true"/>
</properties>
</persistence-unit>
...
I have downloaded H2 1.4.200, the Windows installer, and I installed it on Windows 10. Now using the H2 console I want to connect to the database and inspect the tables, sequences, etc. that were created automatically by Hibernate.
So, going to http://localhost:8082 I get the following:
But when I try to connect to my database, using the defined JDBC connection string, I get the following:
What am I doing wrong here ?
Many thanks in advance.
Nicolas

Finally, I've replaced H2 with Oracle.

play framework 2.6 injecting JPAApi

I am trying to connect my play app with hibernate according to official docs here. My persistence.xml file `http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd"
version="2.1">
<persistence-unit name="defaultPersistenceUnit" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<non-jta-data-source>DefaultDS</non-jta-data-source>
<properties>
<property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
<property name="hibernate.hbm2ddl.auto" value="update"/>
</properties>
</persistence-unit>
`
However, after injecting JPAApi to controller constructor, I'm getting the following error:
`[ERROR] [11/07/2017 17:37:08.944] [play-dev-mode-akka.actor.default-dispatcher-6] [akka.actor.ActorSystemImpl(play-dev-mode)] Internal server error, sending 500 response
com.google.common.util.concurrent.UncheckedExecutionException: java.lang.IllegalArgumentException
at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2218)
at com.google.common.cache.LocalCache.get(LocalCache.java:4147)
at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:4151)
`
It lools like DI mechanism can not find proper realization to JPAApi interface. How can I fix this issue?

JPA / Hibernate : schema generation with multiple persistence units

I have an application that uses a set of JPA entities that are located in 2 different databases. I configured it with multiple persistence units.
The problem is that I want to auto-generate the schema using schema-generation, and all the entities are created in both databases.
I have in both PUs:
<property name="javax.persistence.schema-generation.database.action" value="drop-and-create"/>
<property name="javax.persistence.schema-generation.create-source" value="metadata"/>
<property name="javax.persistence.schema-generation.drop-source" value="metadata"/>
And, yes, I want to use the metadata to get the entities automatically. I do not want to provide a manual script, because I would need to keep it up to date with the entities.
Is there a way to mark which entity to be generated by which PU?
-edit: please be aware that adding "schema" property on #Table does not resolve the problem, because each PU will try to create the same entity in the right schema, and there will be errors because the tables will already exist.

Yes, you can do that. You need to list the entities under each persistant unit, and also DISABLE the auto discovery of the unlisted entities explicitly with <exclude-unlisted-classes>true</exclude-unlisted-classes>.
<!-- Unit 1 -->
<persistence-unit name="Unit1" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.your.class.A</class>
<exclude-unlisted-classes>true</exclude-unlisted-classes>
<properties>
<property name="javax.persistence.jdbc.username" value=""/>
<property name="javax.persistence.jdbc.password" value=""/>
<property name="hibernate.hbm2ddl.auto" value="update"/>
<property name="javax.persistence.schema-generation.database.action" value="drop-and-create"/>
<property name="javax.persistence.schema-generation.create-source" value="metadata"/>
<property name="javax.persistence.schema-generation.drop-source" value="metadata"/>
</properties>
</persistence-unit>
<!-- Unit 2 -->
<persistence-unit name="Unit2" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.your.class.B</class>
<exclude-unlisted-classes>true</exclude-unlisted-classes>
<properties>
<property name="javax.persistence.jdbc.username" value=""/>
<property name="javax.persistence.jdbc.password" value=""/>
<property name="hibernate.hbm2ddl.auto" value="update"/>
<property name="javax.persistence.schema-generation.database.action" value="drop-and-create"/>
<property name="javax.persistence.schema-generation.create-source" value="metadata"/>
<property name="javax.persistence.schema-generation.drop-source" value="metadata"/>
</properties>
</persistence-unit>
Edit
If you are using annotations configuration, then
LocalContainerEntityManagerFactoryBean lef = new LocalContainerEntityManagerFactoryBean();
lef.setPackagesToScan("com.A");
And another factory for another entity manager with a different package name.

I found a way: I will use "schema" property in #Table annotation for each entity and then I would enable only one PU to auto generate the tables.

OpenJpa in Apache Geronimo 3.0

I have a newbie question, so I hope you can help.
Currently as ORM tool I am using OpenJPA 2.2.1 .
MY CUrrent persistence UNit:
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.0"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
<persistence-unit name="FleaCircus" transaction-type="JTA">
<description>Flea Circus</description>
<provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>
<jta-data-source>FleaCircusOracleDS</jta-data-source>
<class>de.carmedialab.db.entities.ApplicationItem</class>
<class>de.carmedialab.db.entities.FleaResult</class>
<class>de.carmedialab.db.entities.FleaResultType</class>
<class>de.carmedialab.db.entities.ItemAttribute</class>
<class>de.carmedialab.db.entities.ItemGroup</class>
<class>de.carmedialab.db.entities.ItemType</class>
<class>de.carmedialab.db.entities.ItemTypeAttribute</class>
<class>de.carmedialab.db.entities.ItemTypeOperationAttribute</class>
<class>de.carmedialab.db.entities.Operation</class>
<class>de.carmedialab.db.entities.OperationAttribute</class>
<class>de.carmedialab.db.entities.OperationType</class>
<class>de.carmedialab.db.entities.Role</class>
<class>de.carmedialab.db.entities.UserAccount</class>
<class>de.carmedialab.db.entities.Measurement</class>
<class>de.carmedialab.db.entities.MeasurementType</class>
<class>de.carmedialab.db.entities.MeasurementAttribute</class>
<class>de.carmedialab.db.entities.MeasurementAttributeType</class>
<class>de.carmedialab.db.entities.Fleet</class>
<properties>
<property name="openjpa.jdbc.SynchronizeMappings" value="validate" />
<property
name="openjpa.Compatibility.CheckDatabaseForCascadePersistToDetachedEntity"
value="true" />
<!--<property name="openjpa.Log"
value="DefaultLevel=WARN, Runtime=INFO, Tool=INFO, SQL=TRACE" />-->
</properties>
</persistence-unit>
<persistence-unit name="FleaCircusLocal" transaction-type="RESOURCE_LOCAL">
<description>Flea Circus</description>
<provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>
<non-jta-data-source>FleaCircusOracleDS</non-jta-data-source>
<class>de.carmedialab.db.entities.ApplicationItem</class>
<class>de.carmedialab.db.entities.FleaResult</class>
<class>de.carmedialab.db.entities.FleaResultType</class>
<class>de.carmedialab.db.entities.ItemAttribute</class>
<class>de.carmedialab.db.entities.ItemGroup</class>
<class>de.carmedialab.db.entities.ItemType</class>
<class>de.carmedialab.db.entities.ItemTypeAttribute</class>
<class>de.carmedialab.db.entities.ItemTypeOperationAttribute</class>
<class>de.carmedialab.db.entities.Operation</class>
<class>de.carmedialab.db.entities.OperationAttribute</class>
<class>de.carmedialab.db.entities.OperationType</class>
<class>de.carmedialab.db.entities.Role</class>
<class>de.carmedialab.db.entities.UserAccount</class>
<class>de.carmedialab.db.entities.Measurement</class>
<class>de.carmedialab.db.entities.MeasurementType</class>
<class>de.carmedialab.db.entities.MeasurementAttribute</class>
<class>de.carmedialab.db.entities.MeasurementAttributeType</class>
<class>de.carmedialab.db.entities.Fleet</class>
<properties>
<property name="openjpa.jdbc.SynchronizeMappings" value="validate" />
<property
name="openjpa.Compatibility.CheckDatabaseForCascadePersistToDetachedEntity"
value="true" />
<!--<property name="openjpa.Log"
value="DefaultLevel=WARN, Runtime=INFO, Tool=INFO, SQL=TRACE" />-->
</properties>
</persistence-unit>
</persistence>
For the sake of simplicity, persistence-unit "FleaCircus" is what I use ( Container Managed Persistence ). FleaCircusLocal is another test pu I created , where I've created a sample stateless bean that basically starts a new transaction, persist an element and commit it.
However it doesn't sinchronize immediatly and customer complains about it.
Is there any way to make OpenJPA makes whats in context immediatly visible to the DB or is it impossible due to the nature as OpenJPA/JPA was thought ?
For me it is not a big deal since data is visible inside the container ( Apache Geronimo ) however for the customer it is important since he wants to connet using 3rd party tool ( eg. SQL Developer to and see if data was inserted or not .)

How to generate table from entities

I am currently working on a seam project using eclipse jpa tools; is it possible to automatically generate sql tables from my entity definitions? If so, how do I achieve this?

It depends on the JPA implementation you are using.
With Hibernate you can specify 'create' or 'update' in the hibernate.hbm2ddl.auto properties in persistence.xml:
<persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0">
<persistence-unit name="yourPersistenceUnit" transaction-type="JTA">
<description>Your Persistence Unit</description>
<jta-data-source>java:/DefaultDS</jta-data-source>
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="hibernate.hbm2ddl.auto" value="create"/>
<property name="hibernate.show_sql" value="true"/>
<property name="hibernate.format_sql" value="true"/>
<property name="hibernate.transaction.flush_before_completion" value="true"/>
<property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
</properties>
</persistence-unit>
</persistence>
Possible values for hibernate.hbm2ddl.auto property are:
create: create database tables and indexes at startup
create-drop: create database tables and indexes at startup and drop at shutdown
update: when the application starts, check the database schema and update as needed adding missing tables and columns
validate: when the application starts, check the database schema and fails if there is some missing table or column.