com.amazon.carbonado.spi

Class LobEngine

java.lang.Object

com.amazon.carbonado.spi.LobEngine

public class LobEngine
extends java.lang.Object

Complete Lob support for repositories, although repository is responsible for binding Lob properties to this engine. Lobs are referenced by locators, which are non-zero long integers. A zero locator is equivalent to null.

Author:

Brian S O'Neill

See Also:

getSupportTrigger(Class, int)

Constructor Summary

Constructors

Constructor and Description
LobEngine(Repository lobRepo, Repository locatorRepo)
LobEngine(Repository lobRepo, SequenceValueProducer locatorSequenceProducer)

Method Summary

Methods

Modifier and Type	Method and Description
Blob	createNewBlob(int blockSize) Returns a new Blob whose length is zero.
Clob	createNewClob(int blockSize) Returns a new Clob whose length is zero.
void	deleteLob(Lob lob) Deletes Lob data, freeing up all space consumed by it.
void	deleteLob(long locator) Deletes Lob data, freeing up all space consumed by it.
Blob	getBlobValue(long locator) Loads a Blob value, without checking if it exists or not.
Clob	getClobValue(long locator) Loads a Clob value, without checking if it exists or not.
long	getLocator(Lob lob) Returns the locator for the given Lob, or zero if null.
<S extends Storable> Trigger<S>	getSupportTrigger(java.lang.Class<S> type, int blockSize) Returns a Trigger for binding to this LobEngine.
static <S extends Storable> boolean	hasLobs(java.lang.Class<S> type)
void	setBlobValue(long locator, Blob data) Stores a value into a Blob, replacing anything that was there before.
void	setBlobValue(long locator, java.io.InputStream data) Stores a value into a Blob, replacing anything that was there before.
void	setClobValue(long locator, Clob data) Stores a value into a Clob, replacing anything that was there before.
void	setClobValue(long locator, java.io.Reader data) Stores a value into a Clob, replacing anything that was there before.

Methods inherited from class java.lang.Object

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

Constructor Detail

LobEngine

public LobEngine(Repository lobRepo,
         Repository locatorRepo)
          throws RepositoryException

Parameters:

lobRepo - storage for Lobs - should not be replicated

locatorRepo - storage for producing unique values for Lob locators - should be root repository

Throws:

RepositoryException

Since:

1.2

LobEngine

public LobEngine(Repository lobRepo,
         SequenceValueProducer locatorSequenceProducer)
          throws RepositoryException

Parameters:

lobRepo - storage for Lobs - should not be replicated

locatorSequenceProducer - source of unique values for Lob locators

Throws:

RepositoryException

Since:

1.2

Method Detail

hasLobs

public static <S extends Storable> boolean hasLobs(java.lang.Class<S> type)

createNewBlob

public Blob createNewBlob(int blockSize)
                   throws PersistException

Returns a new Blob whose length is zero.

Parameters:

blockSize - block size (in bytes) to use

Returns:

new empty Blob

Throws:

PersistException

createNewClob

public Clob createNewClob(int blockSize)
                   throws PersistException

Returns a new Clob whose length is zero.

Parameters:

blockSize - block size (in bytes) to use

Returns:

new empty Clob

Throws:

PersistException

getLocator

public long getLocator(Lob lob)

Returns the locator for the given Lob, or zero if null.

Throws:

java.lang.ClassCastException - if Lob is unrecognized

deleteLob

public void deleteLob(long locator)
               throws PersistException

Deletes Lob data, freeing up all space consumed by it.

Throws:

PersistException

deleteLob

public void deleteLob(Lob lob)
               throws PersistException

Deletes Lob data, freeing up all space consumed by it.

Throws:

PersistException

getBlobValue

public Blob getBlobValue(long locator)

Loads a Blob value, without checking if it exists or not.

Parameters:

locator - lob locator as returned by getLocator

Returns:

Blob value or null

getClobValue

public Clob getClobValue(long locator)

Loads a Clob value, without checking if it exists or not.

Parameters:

locator - lob locator as returned by getLocator

Returns:

Clob value or null

setBlobValue

public void setBlobValue(long locator,
                Blob data)
                  throws PersistException,
                         java.io.IOException

Stores a value into a Blob, replacing anything that was there before. Passing null deletes the Blob, which is a convenience for auto-generated code that may call this method.

Parameters:

locator - lob locator as created by createNewBlob

data - source of data for Blob, which may be null to delete

Throws:

java.lang.IllegalArgumentException - if locator is zero

PersistException

java.io.IOException

setBlobValue

public void setBlobValue(long locator,
                java.io.InputStream data)
                  throws PersistException,
                         java.io.IOException

Stores a value into a Blob, replacing anything that was there before. Passing null deletes the Blob, which is a convenience for auto-generated code that may call this method.

Parameters:

locator - lob locator as created by createNewBlob

data - source of data for Blob, which may be null to delete

Throws:

java.lang.IllegalArgumentException - if locator is zero

PersistException

java.io.IOException

setClobValue

public void setClobValue(long locator,
                Clob data)
                  throws PersistException,
                         java.io.IOException

Stores a value into a Clob, replacing anything that was there before. Passing null deletes the Clob, which is a convenience for auto-generated code that may call this method.

Parameters:

locator - lob locator as created by createNewClob

data - source of data for Clob, which may be null to delete

Throws:

java.lang.IllegalArgumentException - if locator is zero

PersistException

java.io.IOException

setClobValue

public void setClobValue(long locator,
                java.io.Reader data)
                  throws PersistException,
                         java.io.IOException

Stores a value into a Clob, replacing anything that was there before. Passing null deletes the Clob, which is a convenience for auto-generated code that may call this method.

Parameters:

locator - lob locator as created by createNewClob

data - source of data for Clob, which may be null to delete

Throws:

java.lang.IllegalArgumentException - if locator is zero

PersistException

java.io.IOException

getSupportTrigger

public <S extends Storable> Trigger<S> getSupportTrigger(java.lang.Class<S> type,
                                                int blockSize)

Returns a Trigger for binding to this LobEngine. Storage implementations which use LobEngine must install this Trigger. Trigger instances are cached, so subsequent calls for the same trigger return the same instance.

Parameters:

type - type of Storable to create trigger for

blockSize - block size to use

Returns:

support trigger or null if storable type has no lob properties