org.apache.derby.impl.store.access.heap
Class HeapConglomerateFactory

java.lang.Object
  extended byorg.apache.derby.impl.store.access.heap.HeapConglomerateFactory
All Implemented Interfaces:
ConglomerateFactory, MethodFactory, ModuleControl, ModuleSupportable

public class HeapConglomerateFactory
extends java.lang.Object
implements ConglomerateFactory, ModuleControl, ModuleSupportable

The heap conglomerate factory manages heap conglomerates implemented on the raw store.


Field Summary
private  UUID formatUUID
           
private static java.lang.String FORMATUUIDSTRING
           
private static java.lang.String IMPLEMENTATIONID
           
 
Fields inherited from interface org.apache.derby.iapi.store.access.conglomerate.ConglomerateFactory
BTREE_FACTORY_ID, HEAP_FACTORY_ID
 
Fields inherited from interface org.apache.derby.iapi.store.access.conglomerate.MethodFactory
MODULE
 
Constructor Summary
HeapConglomerateFactory()
           
 
Method Summary
 void boot(boolean create, java.util.Properties startParams)
          Boot this module with the given properties.
 boolean canSupport(java.util.Properties startParams)
          See if this implementation can support any attributes that are listed in properties.
 Conglomerate createConglomerate(TransactionManager xact_mgr, int segment, long input_containerid, DataValueDescriptor[] template, ColumnOrdering[] columnOrder, java.util.Properties properties, int temporaryFlag)
          Create the conglomerate and return a conglomerate object for it.
 java.util.Properties defaultProperties()
          Return the default properties for this kind of conglomerate.
 int getConglomerateFactoryId()
          Return the conglomerate factory id.
 UUID primaryFormat()
          Return the primary format that this access method supports.
 java.lang.String primaryImplementationType()
          Return the primary implementation type for this access method.
 Conglomerate readConglomerate(TransactionManager xact_mgr, ContainerKey container_key)
          Return Conglomerate object for conglomerate with container_key.
 void stop()
          Stop the module.
 boolean supportsFormat(UUID formatid)
          Return whether this access method supports the format supplied in the argument.
 boolean supportsImplementation(java.lang.String implementationId)
          Return whether this access method implements the implementation type given in the argument string.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

IMPLEMENTATIONID

private static final java.lang.String IMPLEMENTATIONID
See Also:
Constant Field Values

FORMATUUIDSTRING

private static final java.lang.String FORMATUUIDSTRING
See Also:
Constant Field Values

formatUUID

private UUID formatUUID
Constructor Detail

HeapConglomerateFactory

public HeapConglomerateFactory()
Method Detail

defaultProperties

public java.util.Properties defaultProperties()
Return the default properties for this kind of conglomerate.

Specified by:
defaultProperties in interface MethodFactory
See Also:
MethodFactory.defaultProperties()

supportsImplementation

public boolean supportsImplementation(java.lang.String implementationId)
Return whether this access method implements the implementation type given in the argument string. The heap only has one implementation type, "heap".

Specified by:
supportsImplementation in interface MethodFactory
See Also:
MethodFactory.supportsImplementation(java.lang.String)

primaryImplementationType

public java.lang.String primaryImplementationType()
Return the primary implementation type for this access method. The heap only has one implementation type, "heap".

Specified by:
primaryImplementationType in interface MethodFactory
See Also:
MethodFactory.primaryImplementationType()

supportsFormat

public boolean supportsFormat(UUID formatid)
Return whether this access method supports the format supplied in the argument. The heap currently only supports one format, HEAPFORMAT1.

Specified by:
supportsFormat in interface MethodFactory
See Also:
MethodFactory.supportsFormat(org.apache.derby.catalog.UUID)

primaryFormat

public UUID primaryFormat()
Return the primary format that this access method supports. The heap currently only supports one format, HEAPFORMAT1.

Specified by:
primaryFormat in interface MethodFactory
See Also:
MethodFactory.primaryFormat()

getConglomerateFactoryId

public int getConglomerateFactoryId()
Return the conglomerate factory id.

Return a number in the range of 0-15 which identifies this factory. Code which names conglomerates depends on this range currently, but could be easily changed to handle larger ranges. One hex digit seemed reasonable for the number of conglomerate types being currently considered (heap, btree, gist, gist btree, gist rtree, hash, others? ).

Specified by:
getConglomerateFactoryId in interface ConglomerateFactory
Returns:
an unique identifier used to the factory into the conglomid.
See Also:
ConglomerateFactory.getConglomerateFactoryId()

createConglomerate

public Conglomerate createConglomerate(TransactionManager xact_mgr,
                                       int segment,
                                       long input_containerid,
                                       DataValueDescriptor[] template,
                                       ColumnOrdering[] columnOrder,
                                       java.util.Properties properties,
                                       int temporaryFlag)
                                throws StandardException
Create the conglomerate and return a conglomerate object for it.

Specified by:
createConglomerate in interface ConglomerateFactory
Parameters:
xact_mgr - transaction to perform the create in.
segment - segment to create the conglomerate in.
input_containerid - containerid to assign the container, or ContainerHandle.DEFAULT_ASSIGN_ID if you want raw store to assign an id.
template - Template of row in the conglomerate.
columnOrder - columns sort order for Index creation
properties - Properties associated with the conglomerate.
Throws:
StandardException - Standard exception policy.
See Also:
ConglomerateFactory.createConglomerate(org.apache.derby.iapi.store.access.conglomerate.TransactionManager, int, long, org.apache.derby.iapi.types.DataValueDescriptor[], org.apache.derby.iapi.store.access.ColumnOrdering[], java.util.Properties, int)

readConglomerate

public Conglomerate readConglomerate(TransactionManager xact_mgr,
                                     ContainerKey container_key)
                              throws StandardException
Return Conglomerate object for conglomerate with container_key.

Return the Conglomerate Object. This is implementation specific. Examples of what will be done is using the key to find the file where the conglomerate is located, and then executing implementation specific code to instantiate an object from reading a "special" row from a known location in the file. In the btree case the btree conglomerate is stored as a column in the control row on the root page.

This operation is costly so it is likely an implementation using this will cache the conglomerate row in memory so that subsequent accesses need not perform this operation.

Specified by:
readConglomerate in interface ConglomerateFactory
Parameters:
xact_mgr - transaction to perform the create in.
container_key - The unique id of the existing conglomerate.
Returns:
An instance of the conglomerate.
Throws:
StandardException - Standard exception policy.

canSupport

public boolean canSupport(java.util.Properties startParams)
Description copied from interface: ModuleSupportable
See if this implementation can support any attributes that are listed in properties. This call may be made on a newly created instance before the boot() method has been called, or after the boot method has been called for a running module.

The module can check for attributes in the properties to see if it can fulfill the required behaviour. E.g. the raw store may define an attribute called RawStore.Recoverable. If a temporary raw store is required the property RawStore.recoverable=false would be added to the properties before calling bootServiceModule. If a raw store cannot support this attribute its canSupport method would return null. Also see the Monitor class's prologue to see how the identifier is used in looking up properties.
Actually a better way maybe to have properties of the form RawStore.Attributes.mandatory=recoverable,smallfootprint and RawStore.Attributes.requested=oltp,fast

Specified by:
canSupport in interface ModuleSupportable
Returns:
true if this instance can be used, false otherwise.

boot

public void boot(boolean create,
                 java.util.Properties startParams)
          throws StandardException
Description copied from interface: ModuleControl
Boot this module with the given properties. Creates a module instance that can be found using the findModule() methods of Monitor. The module can only be found using one of these findModule() methods once this method has returned.

An implementation's boot method can throw StandardException. If it is thrown the module is not registered by the monitor and therefore cannot be found through a findModule(). In this case the module's stop() method is not called, thus throwing this exception must free up any resources.

When create is true the contents of the properties object will be written to the service.properties of the persistent service. Thus any code that requires an entry in service.properties must explicitly place the value in this properties set using the put method.
Typically the properties object contains one or more default properties sets, which are not written out to service.properties. These default sets are how callers modify the create process. In a JDBC connection database create the first set of defaults is a properties object that contains the attributes that were set on the jdbc:derby: URL. This attributes properties set has the second default properties set as its default. This set (which could be null) contains the properties that the user set on their DriverManager.getConnection() call, and are thus not owned by cloudscape code, and thus must not be modified by cloudscape code.

When create is false the properties object contains all the properties set in the service.properties file plus a limited number of attributes from the JDBC URL attributes or connection properties set. This avoids properties set by the user compromising the boot process. An example of a property passed in from the JDBC world is the bootPassword for encrypted databases.

Code should not hold onto the passed in properties reference after boot time as its contents may change underneath it. At least after the complete boot is completed, the links to all the default sets will be removed.

Specified by:
boot in interface ModuleControl
Throws:
StandardException - Module cannot be started.
See Also:
Monitor, ModuleFactory

stop

public void stop()
Description copied from interface: ModuleControl
Stop the module. The module may be found via a findModule() method until some time after this method returns. Therefore the factory must be prepared to reject requests to it once it has been stopped. In addition other modules may cache a reference to the module and make requests of it after it has been stopped, these requests should be rejected as well.

Specified by:
stop in interface ModuleControl
See Also:
Monitor, ModuleFactory

Built on Tue 2006-10-10 19:23:47+0200, from revision exported

Apache Derby V10.1 Engine Documentation - Copyright © 1997,2005 The Apache Software Foundation or its licensors, as applicable.