Integration for c3p0 Connection pooling into Hibernate ORM


Keywords
database, envers, gradle, hibernate, java, java8, java8-times, jdbc, jpa, orm, unitofwork
Licenses
LGPL-2.0/GPL-3.0+

Documentation

Hibernate ORM is a powerful object/relational mapping solution for Java, and makes it easy to develop persistence logic for applications, libraries, and frameworks.

Hibernate implements JPA, the standard API for object/relational persistence in Java, but also offers an extensive set of features and APIs which go beyond the specification.

See Hibernate.org for more information.

Build Status Revved%20up%20by Develocity 06A0CE?logo=Gradle&labelColor=02303A

Continuous Integration

Hibernate uses both Jenkins and GitHub Actions for its CI needs. See

Building from sources

The build requires at least Java 11 and at most Java 17.

Hibernate uses Gradle as its build tool. See the Gradle Primer section below if you are new to Gradle.

Contributors should read the Contributing Guide.

See the guides for setting up IntelliJ or Eclipse as your development environment.

Gradle Primer

The Gradle build tool has amazing documentation. 2 in particular that are indispensable:

  • Gradle User Guide is a typical user guide in that it follows a topical approach to describing all of the capabilities of Gradle.

  • Gradle DSL Guide is unique and excellent in quickly getting up to speed on certain aspects of Gradle.

We will cover the basics developers and contributors new to Gradle need to know to get productive quickly.

Note
The project defines a Gradle Wrapper. The rest of the section will assume execution through the wrapper.

Executing Tasks

Gradle uses the concept of build tasks (equivalent to Ant targets or Maven phases/goals). You can get a list of available tasks via

gradle tasks

To execute a task across all modules, simply perform that task from the root directory. Gradle will visit each sub-project and execute that task if the sub-project defines it. To execute a task in a specific module you can either:

  1. cd into that module directory and execute the task

  2. name the "task path". For example, to run the tests for the hibernate-core module from the root directory you could say gradle hibernate-core:test

Common tasks

The common tasks you might use in building Hibernate include:

  • build - Assembles (jars) and tests this project

  • compile - Performs all compilation tasks including staging resources from both main and test

  • jar - Generates a jar archive with all the compiled classes

  • test - Runs the tests

  • publishToMavenLocal - Installs the project jar to your local maven cache (aka ~/.m2/repository). Note that Gradle never uses this, but it can be useful for testing your build with other local Maven-based builds.

  • clean - Cleans the build directory

Testing and databases

Testing against a specific database can be achieved in 2 different ways:

Using the "Matrix Testing Plugin" for Gradle.

Coming later…

Using "profiles"

The Hibernate build defines several database testing "profiles" in databases.gradle. These profiles can be activated by name using the db build property which can be passed either as a JVM system prop (-D) or as a Gradle project property (-P). Examples below use the Gradle project property approach.

gradle clean build -Pdb=pgsql

To run a test from your IDE, you need to ensure the property expansions happen. Use the following command:

gradle clean compile -Pdb=pgsql

NOTE: If you are running tests against a JDBC driver that is not available via Maven central be sure to add these drivers to your local Maven repo cache (~/.m2/repository) or (better) add it to a personal Maven repo server

Running database-specific tests from the IDE using "profiles"

You can run any test on any particular database that is configured in a databases.gradle profile.

All you have to do is run the following command:

./gradlew setDataBase -Pdb=pgsql

or you can use the shortcut version:

./gradlew sDB -Pdb=pgsql

You can do this from the module which you are interested in testing or from the hibernate-orm root folder.

Afterward, just pick any test from the IDE and run it as usual. Hibernate will pick the database configuration from the hibernate.properties file that was set up by the setDataBase Gradle task.

Starting test databases locally as docker containers

You don’t have to install all databases locally to be able to test against them in case you have docker available. The script docker_db.sh allows you to start a pre-configured database which can be used for testing.

All you have to do is run the following command:

./docker_db.sh postgresql

omitting the argument will print a list of possible options.

When the database is properly started, you can run tests with special profiles that are suffixed with _ci e.g. pgsql_ci for PostgreSQL. By using the system property dbHost you can configure the IP address of your docker host.

The command for running tests could look like the following:

./gradlew test -Pdb=pgsql_ci "-DdbHost=192.168.99.100"

The following table illustrates a list of commands for various databases that can be tested locally.

Database docker_db.sh Gradle command

H2

-

./gradlew test -Pdb=h2

HSQLDB

-

./gradlew test -Pdb=hsqldb

Apache Derby

-

./gradlew test -Pdb=derby

MySQL

./docker_db.sh mysql

./gradlew test -Pdb=mysql_ci

MariaDB

./docker_db.sh mariadb

./gradlew test -Pdb=mariadb_ci

PostgreSQL

./docker_db.sh postgresql

./gradlew test -Pdb=pgsql_ci

EnterpriseDB

./docker_db.sh edb

./gradlew test -Pdb=edb_ci

Oracle XE

./docker_db.sh oracle

./gradlew test -Pdb=oracle_free_ci

DB2

./docker_db.sh db2

./gradlew test -Pdb=db2_ci

SQL Server

./docker_db.sh mssql

./gradlew test -Pdb=mssql_ci

Sybase ASE (jTDS)

./docker_db.sh sybase

./gradlew test -Pdb=sybase_ci

Sybase ASE (jConnect)

./docker_db.sh sybase

./gradlew test -Pdb=sybase_jconn_ci

SAP HANA

./docker_db.sh hana

./gradlew test -Pdb=hana_ci

CockroachDB

./docker_db.sh cockroachdb

./gradlew test -Pdb=cockroachdb

TiDB

./docker_db.sh tidb

./gradlew test -Pdb=tidb

To stop a container started by docker, use the command

docker stop $container_name
NOTE

Substitute podman command for docker if using podman

E.g., to stop the mariadb container

docker stop mariadb