com.goldencode.p2j.persist

Class DataSetManager

java.lang.Object

com.goldencode.p2j.persist.DataSetManager

All Implemented Interfaces:

Scopeable

public class DataSetManager
extends java.lang.Object
implements Scopeable

A manager for DataSet-s:

• registers new DataSet-s and matches shared ones;
• keeps the head and tail of the list of DataSet-s.

Field Summary

Fields

Modifier and Type	Field and Description
private BufferManager	bm The buffer helper.
private ScopedDictionary<DataSet,java.lang.Integer>	byReferenceParameters A dictionary of BY-REFERENCE dataset parameters.
private ScopedDictionary<OutputDataSetHandleCopier,java.lang.Integer>	dshOutputParams Scoped dictionary which contains the maps of output copiers for a procedure/function to their 0-based indexes in the set of all DATASET-HANDLE parameters for the procedure/function (excluding other types of parameters).
private static ContextLocal<DataSetManager>	instance The context-local manager.
private java.util.Set<StaticDataSet>	pendingRegistry The pending datasets defined in the next external program being invoked.
private ProcedureManager.ProcedureHelper	pm The procedure helper.
private TransactionManager.TransactionHelper	tm The transaction helper.

Constructor Summary

Constructors

Modifier	Constructor and Description
private	DataSetManager() Default c'tor.

Method Summary

Modifier and Type	Method and Description
void	_registerScopeable() Register the DataSetManager for scope notifications at the current block.
void	addByReferenceParameter(DataSet ds) Register the given dataset as BY-REFERENCE, in the byReferenceParameters dictionary.
DataSet	byName(java.lang.String dsName) Looks up for a DataSet by its name.
static DataSet.Builder	define(java.lang.String legacyName, boolean isShared, boolean isNew) Factory method.
ScopeId	getScopeId() Get the ScopeId for the instance.
static DataSetManager	instance() Obtain the instance of DataSetManager (associated with this work area ?).
boolean	isByReferenceParameter(DataSet ds) Check if the given dataset is passed as a BY-REFERENCE parameter.
boolean	isOutputDataSetHandle(DataSet ds) Check if the specified dataset instance is registered as an OUTPUT argument.
void	register(DataSet dataSet, java.lang.String legacyName, boolean isShared, boolean isNew) Registers a ((new) shared) dataset.
void	registerCurrent(handle dsHandle) Convenient gateway to the transaction manager.
void	registerOutputDataSetHandleCopier(DataSetParameter dsParam, handle dsHandle) Create and register the output table copier.
static void	registerScopeable() Register the DataSetManager for scope notifications at the current block.
void	removeByReferenceParameter(DataSet ds) Deregister the given dataset as BY-REFERENCE, from the byReferenceParameters dictionary.
void	scopeDeleted() Provides a notification that an external scope is about to be deleted.
void	scopeFinished() Provides a notification that a scope is about to be exited.
void	scopeStart(BlockDefinition block) Provides a notification that a new scope is about to be entered.
void	unregisterOutputDataSetHandleCopier(OutputDataSetHandleCopier copier) Unregister the output dataset copier in the current scope.

Methods inherited from class java.lang.Object

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

Field Detail

instance

private static final ContextLocal<DataSetManager> instance

The context-local manager.

pendingRegistry

private java.util.Set<StaticDataSet> pendingRegistry

The pending datasets defined in the next external program being invoked.

dshOutputParams

private final ScopedDictionary<OutputDataSetHandleCopier,java.lang.Integer> dshOutputParams

Scoped dictionary which contains the maps of output copiers for a procedure/function to their 0-based indexes in the set of all DATASET-HANDLE parameters for the procedure/function (excluding other types of parameters).

byReferenceParameters

private final ScopedDictionary<DataSet,java.lang.Integer> byReferenceParameters

A dictionary of BY-REFERENCE dataset parameters.

tm

private final TransactionManager.TransactionHelper tm

The transaction helper.

pm

private final ProcedureManager.ProcedureHelper pm

The procedure helper.

bm

private final BufferManager bm

The buffer helper.

Constructor Detail

DataSetManager

private DataSetManager()

Default c'tor. Marks dictionaries which can use identity maps.

Method Detail

define

public static DataSet.Builder define(java.lang.String legacyName,
                                     boolean isShared,
                                     boolean isNew)

Factory method. Corresponds to DEFINE DATASET statement. Creates a new builder for a new DataSet and returns it for further setting up of options.

Parameters:

legacyName - The legacy name of the DataSet. Used for lookup.

isShared - This is a shared DataSet.

isNew - This is a new DataSet. Only in combination with isShared.

instance

public static DataSetManager instance()

Obtain the instance of DataSetManager (associated with this work area ?).

Returns:

the instance of DataSetManager.

registerScopeable

public static void registerScopeable()

Register the DataSetManager for scope notifications at the current block.

register

public void register(DataSet dataSet,
                     java.lang.String legacyName,
                     boolean isShared,
                     boolean isNew)

Registers a ((new) shared) dataset.

Parameters:

dataSet - The new DataSet to be registered.

legacyName - The legacy name of the DataSet.

isShared - true if this is a SHARED DATASET.

isNew - true if this is a NEW SHARED DATASET.

_registerScopeable

public void _registerScopeable()

Register the DataSetManager for scope notifications at the current block. This is a convenient method when the manager is already retrieved, so that there is no need for a further context look-up.

registerCurrent

public void registerCurrent(handle dsHandle)

Convenient gateway to the transaction manager. This is used to avoid an additional context look-up if the caller already has access to this manager. This is not a good pattern to follow (add a method in data set manager to gateway each method in transaction manager). However, this is the only case we want to have such gateway.

Parameters:

dsHandle - the target to be registered with the transaction manager

byName

public DataSet byName(java.lang.String dsName)

Looks up for a DataSet by its name. Only STATIC dataset are managed.

Parameters:

dsName - The name to search.

Returns:

The DataSet statically named sdName or null is such DataSet is not accessible.

scopeStart

public void scopeStart(BlockDefinition block)

Provides a notification that a new scope is about to be entered.

Specified by:

scopeStart in interface Scopeable

Parameters:

block - The explicit block definition which required this notification.

scopeFinished

public void scopeFinished()

Provides a notification that a scope is about to be exited.

Specified by:

scopeFinished in interface Scopeable

scopeDeleted

public void scopeDeleted()

Provides a notification that an external scope is about to be deleted.

Specified by:

scopeDeleted in interface Scopeable

getScopeId

public ScopeId getScopeId()

Get the ScopeId for the instance.

Specified by:

getScopeId in interface Scopeable

Returns:

ScopeId.DATA_SET_MANAGER.

isByReferenceParameter

public boolean isByReferenceParameter(DataSet ds)

Check if the given dataset is passed as a BY-REFERENCE parameter.

Parameters:

ds - The dataset to check.

Returns:

true if the dataset exists in the byReferenceParameters dictionary.

addByReferenceParameter

public void addByReferenceParameter(DataSet ds)

Register the given dataset as BY-REFERENCE, in the byReferenceParameters dictionary.

Parameters:

ds - The dataset.

removeByReferenceParameter

public void removeByReferenceParameter(DataSet ds)

Deregister the given dataset as BY-REFERENCE, from the byReferenceParameters dictionary.

Parameters:

ds - The dataset.

isOutputDataSetHandle

public boolean isOutputDataSetHandle(DataSet ds)

Check if the specified dataset instance is registered as an OUTPUT argument.

Parameters:

ds - The dataset instance.

Returns:

true if the handle originates from the caller as an OUTPUT argument.

registerOutputDataSetHandleCopier

public void registerOutputDataSetHandleCopier(DataSetParameter dsParam,
                                              handle dsHandle)

Create and register the output table copier.

Parameters:

dsParam - The source dataset parameter.

dsHandle - The target dataset handle..

unregisterOutputDataSetHandleCopier

public void unregisterOutputDataSetHandleCopier(OutputDataSetHandleCopier copier)

Unregister the output dataset copier in the current scope.

Parameters:

copier - Copier to unregister.