Maj_ORM An Object Relational Mapper for Java

A object relational Mapper, store whole java objects in a database, providing an easy mechanism to access Java Bean/Objects/Entities and populate a database.

Maj ORM also contains the logic to produce multiple database connections to both, MySQL, MS SQL and Cassandra, databases. Later we plan to offer automatic backup, failover and production of database schema in an additional premium package.

Current Version, 1.1 - Early Release

Usage: Add MajDbORM-(version).jar to classname or maven or gradle libs The Database ORM system is first loaded by com.majorana.ORM.DbBean.getSingletonLazy() Which may be called as often as you like, but will only produces a single instance. The ORM start up will read from the environment variables for the OS running the JVM, and try to connected to databases with the following structure to the Variables. Majorana_dbname_credname with as name dbname as you wish

The Database Credentials.

Type & Name	Description
Name	Name of the Datasource
DatabaseVariant variant	One of MySQL, MSSQL, Cassanadra (cass insensitive)
String hostAddress	IP Address of Database v4/v6
int port	Port of Database connection
String username	Username for Database connection
String passwd	Password for Database connection
String remoteDatabaseNameAtService	Name of Database Schema on the database connection
int priority	Lowest number is highest priority and becames the name database connection
String group	Database Group (Used by Cassandra)
boolean useSSL	if true use an SSL connection for the database
boolean verifySSLCert	if true verify the SSL Cert for the connection
String isolationLevel	For ACID databases the isolationLevel - what to do about simultaneous updates on the same table
boolean allowPublicKeyRetrieval	Allow MajDbORM to retrieve public keys remotely for connections
String poolName	Name of Pool of Database connections (Zaxxa, MySQL, Ms SQL)
minimumIdleTimeout	Close db connection if idea of more than this many secods
maxPoolSize	Number of (Zaxxa) Maximum Database connections held open at a time
minimumIdleCon	Minimum number of idea database connections (only this pool) to hold open at a time
connectionTimeout	Close connection this many miliseconds

Entity Annotations

Many of the Jakarta/Javax persistance Annotations available as well as extra com.majorana.persist.annot ones Any Entity to be persisted should extends com.majorana.ORM.MajoranaBaseEntity Fields marked with @Column will be persisted to and from the database, But static or transient fields will never be persisted Store the current timestamp when the entity is updatedStore the curremt timestamp when the entity is first createdM

Annotation on Type	From Library	Parameters	Description
Column - for Fields	Jakarta/Javax	Name	Name of Database column
Id - for fields	Jakarta/Jaxax	N/A	Indicate column is a primary key
DirEntityVersion - One class in package	Majorana	int major, int minor	Versioning number for a package or directory, only if the Env Vars DBVersion.major DBVersion.minor are greater or equal to these will the case be automatically loaded
Nullable - Field	Majorana	N/A	Indicated the column may be null
Presave - Method	Majorana	N/A	Indicates a method to run in the Entity before saving to the DB
Postload - Method	Majorana	N/A	Indicates a method to run in the Entity after retriving from the DB
Updateable	Majorana	N/A	Indicate a field should be updated by a CRUD update
PopulatedUpdated - LocalDateTime field	Majorana	N/A
PopulatedCreated - LocalDateTime field	Majorana	N/A

Crud Usage


		DbBean dbb = DbBean.getSingletonLazy();
		dbb.connect();
		YourEntityClass en = new YourEntityClass();
		MultiId id = dbb.store(en);
		int sqlId = id.getId();
		UUID cassId = id.getUUID();
		en.setField("New Date");
		dbb.update(id, en);
		// or
		YourEntityClass en1 = dbb.getBean(YourEntityClass.class, new String[]{"idfield"}, new Integer[]{sqlId}
		dbb.deleteBeanById(id, en1);

ORM Usage


		DbBean dbb = DbBean.getSingletonLazy();
		dbb.connect();
		YourEntityClass en = new YourEntityClass();
		MajoranaAnnotationRepository mar = dbb.getRepo(YourEntityClass.class);
		en = mar.setRandom( mar.repoFields, en, new java.util.Random();
		MultId id = storeBean(id);
		YourEntityClass en1= mar.setRandom( mar.repoFields, en, new java.util.Random();
		int ch = dbb.updateSQL( mar.getUpdateString, en1.getParams(en1));
		YourEntityClass en2 = mar.getBean(YourEntityClass.class, 
			"SELECT "+mar.getReadString(),
			new String[]{ "field1","field2"},
			new Object[]{ en2.getField1(), en2.getField2() };
				
		int ch1 = dbb.deleteBeans(YourEntityClass.class, 
			new String[]{ "id"}, new Integer[]{id};