# hib-connect

Hib-connect provides an interface between the clojure-world and a hibernate database. Hibernate is an ORM (Object Relational Model) that basically provides two functionalities:
1. A uniform interface to many different database systems (abstracting away the difference in SQL-dialects).
2. Persistant storage of (java-)objects and the relations between these objects.

The first item is my primary motivation to develop this system. The system consist of two parts:
1. A code generator that based on a name and a field definition generates:
    a. A .java files containing a class definitions of the stored objects.
    b. A .map.include file that describes the hiberanate mapping.
    c. A .clj file describes the clojure interface for the objects.
2. An connector (bridge) to the hibernate work containing the sessionFactory and the code to translate objects/instances from/to clojure.
 


## Usage
Using the system basically is a n-step procedure
1. Use the vinzi.hib-connect.code-generator to generate the files describing your datastructure
2. Include the generated files in your code-base
     a. The .java files can be compiled to the classes folder.
	 (if you connect to an existing applications you can use those java-files. Just take care that the fully qualified names match)
     b. The .map.include needs to be included in your hibernate mapping
     c. The .clj needs to be include in the 'use' or 'require' of your code.
3. The vinzi.hib-connect.bridge needs to be include in your code.

Calls to the hiberate system require a session. The session is provided by wrapping calls with 'call-in-hib-session'.
When closing the program you need to call 'close-hib' to release the database-connection.

In the file vinzi.hib-connector.demo.clj you find some examples of using the system.

## dependencies
There is no maven-repository for mysql, so you have to download the jar and install it in your local maven-repository via the command (example, so include your own paths and version-numbers):
   mvn install:install-file -DgroupId=mysql-connector-java -DartifactId=mysql-connector-java -Dversion=5.1.17 -Dpackaging=jar -Dfile=/opt/jdbc/mysql-connector-java-5.1.17-bin.jar
This artifact can be used in project.clj as:
  :dependencies [ [mysql-connector-java "5.1.17"]]

## todo's
- Add type-meta data to returned clj-objects (such that assoc is allowed again)
- Add type-checking code to the create-object function and the translator.
- split interface in generate-package and generate object (or prepare a data structure that contains this information)
- generate the hibernateMapping.xml files
- generate the hibernate.cfg.xml files based on data-structure (including config parameters)
- generate directories/folder that do not exist (yet)


## License

Copyright (C) 2012 Vinzi

Distributed under the Eclipse Public License, the same as Clojure.