com.metamatrix.common.id.dbid
Class DBIDGenerator

java.lang.Object
  com.metamatrix.common.id.dbid.DBIDGenerator

public class DBIDGenerator
extends java.lang.Object

Field Summary

static java.lang.String	SERVICE_ID
static java.lang.String	VM_ID

Method Summary

long	getID(java.lang.String context) Call to get a unique id for the given context and by default the the id numbers cannot be rolled over and reused.
long	getID(java.lang.String context, boolean enableRollOver) call to get a unique id for the given context and pass true if the id numbers can be rolled over and reused.
static DBIDGenerator	getInstance()
void	setCacheBlockSize(java.lang.String context, long cache) Call to set the incremental block size for a specific context.
void	setUseMemoryIDGeneration() Call when the persistent storage of ID's is not to be used.
void	setUseMemoryIDGeneration(boolean useInMemory) Call to switch whether persistent storage of ID's is to be used.
void	shutDown() Call when the DBIDGenerator is no longer needed and the database connections can be closed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

VM_ID

public static final java.lang.String VM_ID

See Also:

Constant Field Values

SERVICE_ID

public static final java.lang.String SERVICE_ID

See Also:

Constant Field Values

Method Detail

getID

public long getID(java.lang.String context,
                  boolean enableRollOver)
           throws DBIDGeneratorException

call to get a unique id for the given context and pass true if the id numbers can be rolled over and reused.

Parameters:

context - that identifies a unique entity

enableRollOver - is true if the ids can reused

Returns:

long is the next id

Throws:

DBIDGeneratorException

getID

public long getID(java.lang.String context)
           throws DBIDGeneratorException

Call to get a unique id for the given context and by default the the id numbers cannot be rolled over and reused.

Parameters:

context - that identifies a unique entity

Returns:

long is the next id

Throws:

DBIDGeneratorException

setCacheBlockSize

public void setCacheBlockSize(java.lang.String context,
                              long cache)
                       throws DBIDGeneratorException

Call to set the incremental block size for a specific context. This is a way to tune the caching which will reduce the number of database reads that occur. By increasing the cache, it should reduce the number of database reads.

Parameters:

context - that identifies a unique entity

cache - is the size of the blocks to use

Throws:

DBIDGeneratorException

setUseMemoryIDGeneration

public void setUseMemoryIDGeneration()

Call when the persistent storage of ID's is not to be used. This will cause the id's to be generated in memory and will not be written to the database for later use for a starting point. This was made available for the CDK because it needs to load runtime metadata disconnected from the application server or database.

setUseMemoryIDGeneration

public void setUseMemoryIDGeneration(boolean useInMemory)

Call to switch whether persistent storage of ID's is to be used.

Parameters:

useInMemory - whether or not to use in Memory ID generation

shutDown

public void shutDown()

Call when the DBIDGenerator is no longer needed and the database connections can be closed.

getInstance

public static DBIDGenerator getInstance()