org.apache.avalon.excalibur.datasource.ids

Class AbstractIdGenerator

java.lang.Object

org.apache.avalon.framework.logger.AbstractLogEnabled

org.apache.avalon.excalibur.datasource.ids.AbstractIdGenerator

All Implemented Interfaces:

IdGenerator, org.apache.avalon.framework.component.Component, org.apache.avalon.framework.logger.LogEnabled, org.apache.avalon.framework.thread.ThreadSafe

Direct Known Subclasses:

AbstractDataSourceIdGenerator

public abstract class AbstractIdGenerator
extends org.apache.avalon.framework.logger.AbstractLogEnabled
implements IdGenerator, org.apache.avalon.framework.thread.ThreadSafe

Since:

4.1

Version:

CVS $Revision: 1.4 $ $Date: 2004/02/28 11:47:17 $

Author:

Avalon Development Team

Field Summary

Fields

Modifier and Type	Field and Description
private static java.math.BigDecimal	BIG_DECIMAL_MAX_LONG
private java.lang.Object	m_semaphore Used to manage internal synchronization.
private boolean	m_useBigDecimals Data type for the Id Pool.

Fields inherited from interface org.apache.avalon.excalibur.datasource.ids.IdGenerator

ROLE

Constructor Summary

Constructors

Constructor and Description
AbstractIdGenerator()

Method Summary

Methods

Modifier and Type	Method and Description
java.math.BigDecimal	getNextBigDecimalId() Returns the next Id from the pool.
protected abstract java.math.BigDecimal	getNextBigDecimalIdInner() Gets the next id as a Big Decimal.
byte	getNextByteId() Returns the next Id from the pool.
int	getNextIntegerId() Returns the next Id from the pool.
long	getNextLongId() Returns the next Id from the pool.
protected long	getNextLongIdChecked(long maxId) Gets the next Long Id constraining the value to be less than the specified maxId.
protected abstract long	getNextLongIdInner() Gets the next id as a long.
short	getNextShortId() Returns the next Id from the pool.
protected boolean	isUsingBigDecimals() Returns true if the internal data type is using BigDecimals, false if it is using longs.
protected void	setUseBigDecimals(boolean useBigDecimals) By default, the IdGenerator will operate using a backend datatype of type long.

Methods inherited from class org.apache.avalon.framework.logger.AbstractLogEnabled

enableLogging, getLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

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

Field Detail

BIG_DECIMAL_MAX_LONG

private static final java.math.BigDecimal BIG_DECIMAL_MAX_LONG

m_semaphore

private java.lang.Object m_semaphore

Used to manage internal synchronization.

m_useBigDecimals

private boolean m_useBigDecimals

Data type for the Id Pool.

Constructor Detail

AbstractIdGenerator

public AbstractIdGenerator()

Method Detail

getNextBigDecimalIdInner

protected abstract java.math.BigDecimal getNextBigDecimalIdInner()
                                                          throws IdException

Gets the next id as a Big Decimal. This method will only be called when synchronized and when the data type is configured to be BigDecimal.

Returns:

the next id as a BigDecimal.

Throws:

IdException - if an Id could not be allocated for any reason.

getNextLongIdInner

protected abstract long getNextLongIdInner()
                                    throws IdException

Gets the next id as a long. This method will only be called when synchronized and when the data type is configured to be long.

Returns:

the next id as a long.

Throws:

IdException - if an Id could not be allocated for any reason.

setUseBigDecimals

protected final void setUseBigDecimals(boolean useBigDecimals)

By default, the IdGenerator will operate using a backend datatype of type long. This is the most efficient, however it does not allow for Ids that are larger than Long.MAX_VALUE. To allow very large Ids, it is necessary to make use of the BigDecimal data storage type. This method should only be called durring initialization.

Parameters:

useBigDecimals - True to set BigDecimal as the internal data type.

isUsingBigDecimals

protected final boolean isUsingBigDecimals()

Returns true if the internal data type is using BigDecimals, false if it is using longs.

getNextLongIdChecked

protected final long getNextLongIdChecked(long maxId)
                                   throws IdException

Gets the next Long Id constraining the value to be less than the specified maxId.

Throws:

IdException - if the next id is larger than the specified maxId.

getNextBigDecimalId

public final java.math.BigDecimal getNextBigDecimalId()
                                               throws IdException

Returns the next Id from the pool.

Specified by:

getNextBigDecimalId in interface IdGenerator

Returns:

the next Id.

Throws:

IdException

getNextLongId

public final long getNextLongId()
                         throws IdException

Returns the next Id from the pool.

Specified by:

getNextLongId in interface IdGenerator

Returns:

the next Id.

Throws:

IdException - if the next id is outside of the range of valid longs.

getNextIntegerId

public final int getNextIntegerId()
                           throws IdException

Returns the next Id from the pool.

Specified by:

getNextIntegerId in interface IdGenerator

Returns:

the next Id.

Throws:

IdException - if the next id is outside of the range of valid integers.

getNextShortId

public final short getNextShortId()
                           throws IdException

Returns the next Id from the pool.

Specified by:

getNextShortId in interface IdGenerator

Returns:

the next Id.

Throws:

IdException - if the next id is outside of the range of valid shorts.

getNextByteId

public final byte getNextByteId()
                         throws IdException

Returns the next Id from the pool.

Specified by:

getNextByteId in interface IdGenerator

Returns:

the next Id.

Throws:

IdException - if the next id is outside of the range of valid bytes.