Apache ObJectRelationalBridge (OJB) is an Object/Relational mapping tool that allows transparent persistence for

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Objects against

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s. It was released on April 6, 2005. As of January 16, 2011 Apache ObJectRelationalBridge has been retired.Apache ObJectRelationalBridge (OJB)
Apache Software Foundation.

Features

OJB is an ''

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'' project. It is lightweight and easy to use, requiring simply configure two files to implement a persistence layer. It is easy to integrate into an existing application because it does not generate code. It allows the use of different patterns of persistence: owner (PersistenceBroker

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), JDO and Object Data Management Group ( ODMG).

Functionality

OJB uses an

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based Object/Relational mapping. The mapping resides in a dynamic

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layer, which can be manipulated at runtime through a simple Meta-Object-Protocol (MOP) to change the behaviour of the

persistence Persistence or Persist may refer to: Math and computers * Image persistence, in LCD monitors * Persistence (computer science), the characteristic of data that outlives the execution of the program that created it * Persistence of a number, a ma ...

kernel.

Configuration

At least two files are required to configure OJB: OJB.properties and repository.xml

Allocation

For mapping a 1-1 relationship, for example, you have two tables: person and account. In this case, a person has an account and vice versa.

References

External links