| org.apache.ojb.broker.util.sequence |
|
sequence manager package
This package contains classes that provide the OJB sequence numering.
|
| Java Source File Name | Type | Comment |
| AbstractSequenceManager.java | Class | A base class for sequence manager implementations. |
| HighLowSequence.java | Class | The HighLowSequence is the persistent part of the
SequenceManagerHighLowImpl . |
| SequenceManager.java | Interface | SequenceManagers are responsible for creating new unique
ID's - unique accross all "extent" object declarations in OJB metadata. |
| SequenceManagerException.java | Class | An exception thrown by
org.apache.ojb.broker.util.sequence.SequenceManager implementations. |
| SequenceManagerFactory.java | Class | Threadsafe factory class, creates SequenceManager instances. |
| SequenceManagerHelper.java | Class | Helper class for SequenceManager implementations. |
| SequenceManagerHighLowImpl.java | Class | High/Low sequence manager implementation generates unique and continuous
id's (during runtime) by using sequences to avoid database access.
Implementation configuration properties:
| Property Key |
Property Values |
| seq.start |
Set the start index of used sequences (e.g. | | SequenceManagerInMemoryImpl.java | Class |
Very fast in memory sequence manager implementation, only the first
time an id was requested for a class, the manager query the database
for the max id in requested column - all following request were
performed in memory.
Limitations:
- do not use in clustered environments
- do not use if other applications generate id's for objects
Implementation configuration properties:
| Property Key |
Property Values |
| seq.start |
Set the start index of used sequences (e.g. | | SequenceManagerMSSQLGuidImpl.java | Class | An Implementation Class that will retrieve a valid new value
for a PK field that is of type 'uniqueidentifier'. | | SequenceManagerNativeImpl.java | Class | Sequence manager implementation using native database Identity columns
(like MySQL, MSSQL, ...). | | SequenceManagerNextValImpl.java | Class | This SequenceManager implementation uses database
sequence key generation (e.g supported by
Oracle, SAP DB, PostgreSQL, ...).
This class is responsible for creating new unique ID's.
It is possible to define a sequence-name
field-descriptor attribute in the repository file. | | SequenceManagerSeqHiLoImpl.java | Class |
A High/Low database sequence based implementation.
See
org.apache.ojb.broker.util.sequence.SequenceManagerNextValImpl for more information.
Implementation configuration properties:
| Property Key |
Property Values |
| grabSize |
Integer entry determines the
number of IDs allocated within the
H/L sequence manager implementation.
Default was '20'.
|
| autoNaming |
Default was 'true'. | | SequenceManagerStoredProcedureImpl.java | Class | This solution will give those seeking an oracle-style
sequence generator a final answer (Identity columns really suck).
The SequenceManagerStoredProcedureImpl implementation enabled database
sequence key generation for all databases (e.g. | | SequenceManagerTransientImpl.java | Class | For internal use only!
This class is used to create transient primary key values for transient
org.apache.ojb.broker.Identity objects. |
| | | www.java2java.com | Contact Us | | Copyright 2009 - 12 Demo Source and Support. All rights reserved. | | All other trademarks are property of their respective owners. |
|