org.apache.derby.impl.store.raw.data
Class StreamFileContainerHandle

java.lang.Object
  org.apache.derby.impl.store.raw.data.StreamFileContainerHandle

All Implemented Interfaces:

java.util.Observer, StreamContainerHandle

final class StreamFileContainerHandle
extends java.lang.Object
implements StreamContainerHandle, java.util.Observer

A handle to an open stream container, implememts StreamContainerHandle.

This class is an Observer to observe RawTransactions
MT - Mutable - Immutable identity - Thread Aware

Field Summary

protected boolean	active Is this StreamContainerHandle active.
protected StreamFileContainer	container The actual container we are accessing.
private boolean	hold Whether this container should be held open across commit.
protected ContainerKey	identity Container identifier MT - Immutable
private UUID	rawStoreId Raw Store identifier MT - Immutable
protected RawTransaction	xact our transaction.

Fields inherited from interface org.apache.derby.iapi.store.raw.StreamContainerHandle

TEMPORARY_SEGMENT

Constructor Summary

StreamFileContainerHandle(UUID rawStoreId, RawTransaction xact, ContainerKey identity, boolean hold)

StreamFileContainerHandle(UUID rawStoreId, RawTransaction xact, StreamFileContainer container, boolean hold)

Method Summary

void	close() Close me.
boolean	fetchNext(DataValueDescriptor[] row) fetch a row from the container.
void	getContainerProperties(java.util.Properties prop) Request the system properties associated with a container.
ContainerKey	getId() get the container key for the stream container
RawTransaction	getTransaction() Return the RawTransaction this object was opened in.
void	removeContainer() remove the stream container
java.lang.String	toString()
void	update(java.util.Observable obj, java.lang.Object arg) Called when the transaction is about to complete.
boolean	useContainer() Attach me to a container.

Methods inherited from class java.lang.Object

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

Field Detail

rawStoreId

private final UUID rawStoreId

Raw Store identifier
MT - Immutable

identity

protected final ContainerKey identity

Container identifier
MT - Immutable

active

protected boolean active

Is this StreamContainerHandle active.
MT - Mutable : scoped

container

protected StreamFileContainer container

The actual container we are accessing. Only valid when active is true.
MT - Mutable : scoped

xact

protected RawTransaction xact

our transaction. Only valid when active is true.
MT - Mutable : scoped

hold

private boolean hold

Whether this container should be held open across commit. Only valid when active is true.
MT - Mutable : scoped

Constructor Detail

StreamFileContainerHandle

public StreamFileContainerHandle(UUID rawStoreId,
                                 RawTransaction xact,
                                 ContainerKey identity,
                                 boolean hold)

StreamFileContainerHandle

public StreamFileContainerHandle(UUID rawStoreId,
                                 RawTransaction xact,
                                 StreamFileContainer container,
                                 boolean hold)

Method Detail

getContainerProperties

public void getContainerProperties(java.util.Properties prop)
                            throws StandardException

Request the system properties associated with a container.

Specified by:

getContainerProperties in interface StreamContainerHandle

Parameters:

prop - Property list to fill in.

Throws:

StandardException - Standard exception policy.

See Also:

StreamContainerHandle.getContainerProperties(java.util.Properties)

fetchNext

public boolean fetchNext(DataValueDescriptor[] row)
                  throws StandardException

fetch a row from the container.

Specified by:

fetchNext in interface StreamContainerHandle

Parameters:

row - Row to be filled in with information from the record.

Throws:

StandardException - Standard exception policy.

close

public void close()

Description copied from interface: StreamContainerHandle

Close me. After using this method the caller must throw away the reference to the Container object, e.g.

                        ref.close();
                        ref = null;
                

The container will be closed automatically at the commit or abort of the transaction if this method is not called explictly.

Specified by:

close in interface StreamContainerHandle

Throws:

StandardException - Standard exception policy.

See Also:

StreamContainerHandle.close()

removeContainer

public void removeContainer()
                     throws StandardException

remove the stream container

Specified by:

removeContainer in interface StreamContainerHandle

Throws:

StandardException - Standard Derby error policy

See Also:

StreamContainerHandle.removeContainer()

getId

public ContainerKey getId()

get the container key for the stream container

Specified by:

getId in interface StreamContainerHandle

update

public void update(java.util.Observable obj,
                   java.lang.Object arg)

Called when the transaction is about to complete.

Specified by:

update in interface java.util.Observer

See Also:

Observer.update(java.util.Observable, java.lang.Object)

useContainer

public boolean useContainer()
                     throws StandardException

Attach me to a container. If this method returns false then I cannot be used anymore, and any reference to me must be discarded.

Throws:

StandardException - Standard Derby error policy

getTransaction

public final RawTransaction getTransaction()

Return the RawTransaction this object was opened in.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object