Bin2DataStreamer

Default constructor that creates an instance of Bin2DataStreamer

constructor

Bin2DataStreamer()

class method constructor <clinit>(+)

static void constructor <clinit>(+ )

Parameters:

• :

Used in write mode, to store offsets of streamed elements.

method doFinalizeStreamer

void doFinalizeStreamer()

Abstract method that is used internaly by initializeStreamer method.

method doInitializeStreamer(aSource: Object; aMode: StreamerInitialization)

void doInitializeStreamer(Object aSource, StreamerInitialization aMode)

Parameters:

• aSource: a data for the streamer to worm with(usually a string or a stream).
• aMode: an initialization mode of the streamer.

method doInitializeStreamer(source: Object; streamerMode: StreamerInitialization)

void doInitializeStreamer(Object source, StreamerInitialization streamerMode)

Parameters:

• source:
• streamerMode:

Fills the instantiated and named instance of the data table (second parameter) with the data from the stream. The data will be read according to the information and offsets provided in StreamElementInfo (first parameter). Loads all data records from the stream without loading table structure/schema.

method doReadDataTable(anElement: StreamElementInfo; aDestination: DataTable)

void doReadDataTable(StreamElementInfo anElement, DataTable aDestination)

Parameters:

• anElement: An information about the position of data in the stream.
• aDestination: A table instance that should be filled with data.

Fills the instantiated and named instance of the data table (second parameter) with the data from the stream. The data will be read according to the information and offsets provided in StreamElementInfo (first parameter). Loads all data records from the stream.

method doReadDataTable(anElement: StreamElementInfo; aDestination: DataTable; ApplySchema: Boolean)

void doReadDataTable(StreamElementInfo anElement, DataTable aDestination, Boolean ApplySchema)

Parameters:

• anElement: An information about the position of data in the stream.
• aDestination: A table instance that should be filled with data.
• ApplySchema: Defines whether or not to apply schema from stream to the given table instance. Usually pass true here, if table haven't previously loaded or server's schema has changed.

Abstract method that is used internally by readDataTable method.

method doReadDataTable(element: StreamElementInfo; destination: DataTable)

void doReadDataTable(StreamElementInfo element, DataTable destination)

Parameters:

• element: A stream element the represents table in the destination object.
• destination: A target data table object to store read data.

Abstract method that is used internally by readDataTable method.

method doReadDataTable(element: StreamElementInfo; destination: DataTable; applySchema: Boolean)

void doReadDataTable(StreamElementInfo element, DataTable destination, Boolean applySchema)

Parameters:

• element: A stream element the represents table in the destination object.
• destination: A target data table object to store read data.
• applySchema: The flag defines, if a Schema should be applied to the given table.

Initializes the streamer to work in the given mode (second parameter).

method doReadDataTable(element: StreamElementInfo; destination: DataTable; applySchema: Boolean; loadRecords: Boolean)

void doReadDataTable(StreamElementInfo element, DataTable destination, Boolean applySchema, Boolean loadRecords)

Parameters:

• element: An information about the position of data in the stream.
• destination: A table instance that should be filled with data.
• applySchema: Defines whether or not to apply schema from stream to the given table instance. Usually pass true here, if table haven't previously loaded or server's schema has changed.
• loadRecords: Defines whether or not to load table data from the stream. Set it to false if you jjust want to have table structure on client.

Reads the table's schema by the given table's name.

method doReadDataTableSchema(aDataTableName: String): SchemaDataTable

SchemaDataTable doReadDataTableSchema(String aDataTableName)

Parameters:

• aDataTableName: A table name to read schema for.

Abstract method that is used internally by readDelta method.

method doReadDelta(anElement: StreamElementInfo; aDestination: Delta)

void doReadDelta(StreamElementInfo anElement, Delta aDestination)

Parameters:

• anElement: A stream element the represents table in destination object.
• aDestination: A delta object to be filled.

method doReadDelta(element: StreamElementInfo; destination: Delta)

void doReadDelta(StreamElementInfo element, Delta destination)

Parameters:

• element:
• destination:

Writes the given data table to the related stream.

method doWriteDataTable(aTable: DataTable; aTableSchema: SchemaDataTable; aMaxRecords: Integer; aIncludeSchema: Boolean)

void doWriteDataTable(DataTable aTable, SchemaDataTable aTableSchema, Integer aMaxRecords, Boolean aIncludeSchema)

Parameters:

• aTable: The table to write.
• aTableSchema: A table's schema to use during writing.
• aMaxRecords: Max number of records from the table to store in the steam.
• aIncludeSchema: Defines wheter or not to include table's schema in the stream.

Abstract method that is used internally by writeDelta method.

method doWriteDelta(aDelta: Delta; aDynamicSelect: Boolean)

void doWriteDelta(Delta aDelta, Boolean aDynamicSelect)

Parameters:

• aDelta: A delta to be streamed.
• aDynamicSelect: A flag defines whether or not the streamer should use Dynamic Select feature while writing the delta.

Initializes the streamer to work in the given mode (second parameter).

method doWriteDelta(delta: Delta; dynamicSelect: Boolean)

void doWriteDelta(Delta delta, Boolean dynamicSelect)

Parameters:

• delta: A stream to use during streaming. Stream should be seekable.
• dynamicSelect: A mode of the current streamer operation.

property Elements: Map<String, StreamElementInfo> read;

Map<String, StreamElementInfo> Elements { __get; }

The method finalizes the reading/writing of data. It should be called after all elements are written or when reading is complete.

method finalizeStreamer

void finalizeStreamer()

class method getLoggedDeltaFields(delta: Delta; fields: ReferenceType<array of SchemaField>; mapping: ReferenceType<array of Integer>)

static void getLoggedDeltaFields(Delta delta, ReferenceType<array of SchemaField> fields, ReferenceType<array of Integer> mapping)

Parameters:

• delta:
• fields:
• mapping:

property InitializationMode: StreamerInitialization read;

StreamerInitialization InitializationMode { __get; }

This method initializes current streamer object. First parameter should contain the stream or String containing the data to process. All other read/wirte streamer methods will use this given object as a source to read from or as a destination to write to. Second parameter should contain the mode in which this Streamer should be initialized.

method initializeStreamer(aSource: Object; aStreamerMode: StreamerInitialization)

void initializeStreamer(Object aSource, StreamerInitialization aStreamerMode)

Parameters:

• aSource: a data for the streamer to worm with(usually a string or a stream).
• aStreamerMode: an initialization mode of the streamer.

This method checks if a value was initialized by the DB or the server.

class method isDbValueAssigned(aValue: Object): Boolean

static Boolean isDbValueAssigned(Object aValue)

Parameters:

• aValue: avalue to check.

The method returns a prepered key for the given table name, that will be used internally in the streamer to identify the table.

class method makeTableKey(aTableName: String): String

static String makeTableKey(String aTableName)

Parameters:

• aTableName: A name of the data table.

The method checks if specific row value must be included wile streaming data. It can be ommited, if if hasn't been changed. This approach is ussed in Reduced Delta feature of Bin2DataStreamer.

method needIncludeValuesToStream(aOldValue: Object; aNewValue: Object; aIsReducedDelta: Boolean; aIsPK: Boolean; aIncludeOld: ReferenceType<Boolean>; aIncludeNew: ReferenceType<Boolean>): Boolean

Boolean needIncludeValuesToStream(Object aOldValue, Object aNewValue, Boolean aIsReducedDelta, Boolean aIsPK, ReferenceType<Boolean> aIncludeOld, ReferenceType<Boolean> aIncludeNew)

Parameters:

• aOldValue: An original field value.
• aNewValue: A new field value.
• aIsReducedDelta: A flag defines whether or not the delta should be reduced.
• aIsPK: The flag used to define whether of not the field belongs to the primary key.
• aIncludeOld: out param returns whether or not the original value is supposed to be included.
• aIncludeNew: out param returns whether or not the new value is supposed to be included.

Reads the contents of a DataTable from the stream. This method will throw an exception if no DataTable can be found in the stream by the name passed in the first parameter.

Some cases of usage:

  // to load data without schema (in case table has been previously initialized with the schema):
  streamer.readDataTable("Clients", table, <tt>false</tt>, <tt>true</tt>);
  // to initialize the table column structure without loading the ctual data:
  streamer.readDataTable("Clients", table, <tt>true</tt>, <tt>false</tt>);

method readDataTable(aDataTableName: String; aDestination: DataTable; aApplySchema: Boolean; aLoadRecords: Boolean)

void readDataTable(String aDataTableName, DataTable aDestination, Boolean aApplySchema, Boolean aLoadRecords)

Parameters:

• aDataTableName: A name of the data table to be read.
• aDestination: A data table object to fill with tha data.
• aApplySchema: The flag defines, if a Schema should be applied to the given table.
• aLoadRecords: The flag defines, if method should load data for the table.

The method reads the schema for the given table name and returns it.

method readDataTableSchema(aDataTableName: String): SchemaDataTable

SchemaDataTable readDataTableSchema(String aDataTableName)

Parameters:

• aDataTableName: A name of the data table.

The method returns a delta from the provided source. If there is no delta by the name passed it will throw an exception.

method readDelta(aDestination: Delta)

void readDelta(Delta aDestination)

Parameters:

• aDestination: A delta object to be filled.

The method creates a new Delta object using the given Schema and fills it from the source associated with the streamer.

method readDelta(aSchema: Schema; aTableName: String): Delta

Delta readDelta(Schema aSchema, String aTableName)

Parameters:

• aSchema: A schema for a new delta.
• aTableName: A table name, that is used to find delta's data in the streamer's source.

property SendReducedDelta: Boolean read write;

Boolean SendReducedDelta { __get; __set; }

The method writes a DataTable to the streamer destination. This method will throw an exception if a DataTable by the same name already exists in the stream.

method writeDataTable(aTable: DataTable; aTableSchema: SchemaDataTable; aMaxRecords: Integer; aIncludeSchema: Boolean)

void writeDataTable(DataTable aTable, SchemaDataTable aTableSchema, Integer aMaxRecords, Boolean aIncludeSchema)

Parameters:

• aTable: A data table to stream.
• aTableSchema: A data table's schema to use while streaming.
• aMaxRecords: A number of maximum table records the server supposed to send back to the client.
• aIncludeSchema: The flag defines wheter or not server should include table schema in response.

The method creates Delta from the given data table and writes it to the streamer destination. If there is already a delta with this name it will throw an exception.

method writeDelta(aDataTable: DataTable; aDynamicSelect: Boolean): Delta

Delta writeDelta(DataTable aDataTable, Boolean aDynamicSelect)

Parameters:

• aDataTable: A data table to creade delta from.
• aDynamicSelect: A flag that defines whether or not stremaer should use a Dynamic Select feature while streaming the delta.

The method streams the gived delta considering usage of Dynamic Select feature.

method writeDelta(aDelta: Delta; aDynamicSelect: Boolean)

void writeDelta(Delta aDelta, Boolean aDynamicSelect)

Parameters:

• aDelta: A delta to be streamed.
• aDynamicSelect: A flag defines whether or not the streamer should use Dynamic Select feature while writing the delta.

class method constructor <clinit>(+)

static void constructor <clinit>(+ )

Parameters:

• :

class method getLoggedDeltaFields(delta: Delta; fields: ReferenceType<array of SchemaField>; mapping: ReferenceType<array of Integer>)

static void getLoggedDeltaFields(Delta delta, ReferenceType<array of SchemaField> fields, ReferenceType<array of Integer> mapping)

Parameters:

• delta:
• fields:
• mapping:

This method checks if a value was initialized by the DB or the server.

class method isDbValueAssigned(aValue: Object): Boolean

static Boolean isDbValueAssigned(Object aValue)

Parameters:

• aValue: avalue to check.

The method returns a prepered key for the given table name, that will be used internally in the streamer to identify the table.

class method makeTableKey(aTableName: String): String

static String makeTableKey(String aTableName)

Parameters:

• aTableName: A name of the data table.

Default constructor that creates an instance of Bin2DataStreamer

constructor

Bin2DataStreamer()

Used in write mode, to store offsets of streamed elements.

method doFinalizeStreamer

void doFinalizeStreamer()

Abstract method that is used internaly by initializeStreamer method.

method doInitializeStreamer(aSource: Object; aMode: StreamerInitialization)

void doInitializeStreamer(Object aSource, StreamerInitialization aMode)

Parameters:

• aSource: a data for the streamer to worm with(usually a string or a stream).
• aMode: an initialization mode of the streamer.

method doInitializeStreamer(source: Object; streamerMode: StreamerInitialization)

void doInitializeStreamer(Object source, StreamerInitialization streamerMode)

Parameters:

• source:
• streamerMode:

Fills the instantiated and named instance of the data table (second parameter) with the data from the stream. The data will be read according to the information and offsets provided in StreamElementInfo (first parameter). Loads all data records from the stream without loading table structure/schema.

method doReadDataTable(anElement: StreamElementInfo; aDestination: DataTable)

void doReadDataTable(StreamElementInfo anElement, DataTable aDestination)

Parameters:

• anElement: An information about the position of data in the stream.
• aDestination: A table instance that should be filled with data.

Fills the instantiated and named instance of the data table (second parameter) with the data from the stream. The data will be read according to the information and offsets provided in StreamElementInfo (first parameter). Loads all data records from the stream.

method doReadDataTable(anElement: StreamElementInfo; aDestination: DataTable; ApplySchema: Boolean)

void doReadDataTable(StreamElementInfo anElement, DataTable aDestination, Boolean ApplySchema)

Parameters:

• anElement: An information about the position of data in the stream.
• aDestination: A table instance that should be filled with data.
• ApplySchema: Defines whether or not to apply schema from stream to the given table instance. Usually pass true here, if table haven't previously loaded or server's schema has changed.

Abstract method that is used internally by readDataTable method.

method doReadDataTable(element: StreamElementInfo; destination: DataTable)

void doReadDataTable(StreamElementInfo element, DataTable destination)

Parameters:

• element: A stream element the represents table in the destination object.
• destination: A target data table object to store read data.

Abstract method that is used internally by readDataTable method.

method doReadDataTable(element: StreamElementInfo; destination: DataTable; applySchema: Boolean)

void doReadDataTable(StreamElementInfo element, DataTable destination, Boolean applySchema)

Parameters:

• element: A stream element the represents table in the destination object.
• destination: A target data table object to store read data.
• applySchema: The flag defines, if a Schema should be applied to the given table.

Initializes the streamer to work in the given mode (second parameter).

method doReadDataTable(element: StreamElementInfo; destination: DataTable; applySchema: Boolean; loadRecords: Boolean)

void doReadDataTable(StreamElementInfo element, DataTable destination, Boolean applySchema, Boolean loadRecords)

Parameters:

• element: An information about the position of data in the stream.
• destination: A table instance that should be filled with data.
• applySchema: Defines whether or not to apply schema from stream to the given table instance. Usually pass true here, if table haven't previously loaded or server's schema has changed.
• loadRecords: Defines whether or not to load table data from the stream. Set it to false if you jjust want to have table structure on client.

Reads the table's schema by the given table's name.

method doReadDataTableSchema(aDataTableName: String): SchemaDataTable

SchemaDataTable doReadDataTableSchema(String aDataTableName)

Parameters:

• aDataTableName: A table name to read schema for.

Abstract method that is used internally by readDelta method.

method doReadDelta(anElement: StreamElementInfo; aDestination: Delta)

void doReadDelta(StreamElementInfo anElement, Delta aDestination)

Parameters:

• anElement: A stream element the represents table in destination object.
• aDestination: A delta object to be filled.

method doReadDelta(element: StreamElementInfo; destination: Delta)

void doReadDelta(StreamElementInfo element, Delta destination)

Parameters:

• element:
• destination:

Writes the given data table to the related stream.

method doWriteDataTable(aTable: DataTable; aTableSchema: SchemaDataTable; aMaxRecords: Integer; aIncludeSchema: Boolean)

void doWriteDataTable(DataTable aTable, SchemaDataTable aTableSchema, Integer aMaxRecords, Boolean aIncludeSchema)

Parameters:

• aTable: The table to write.
• aTableSchema: A table's schema to use during writing.
• aMaxRecords: Max number of records from the table to store in the steam.
• aIncludeSchema: Defines wheter or not to include table's schema in the stream.

Abstract method that is used internally by writeDelta method.

method doWriteDelta(aDelta: Delta; aDynamicSelect: Boolean)

void doWriteDelta(Delta aDelta, Boolean aDynamicSelect)

Parameters:

• aDelta: A delta to be streamed.
• aDynamicSelect: A flag defines whether or not the streamer should use Dynamic Select feature while writing the delta.

Initializes the streamer to work in the given mode (second parameter).

method doWriteDelta(delta: Delta; dynamicSelect: Boolean)

void doWriteDelta(Delta delta, Boolean dynamicSelect)

Parameters:

• delta: A stream to use during streaming. Stream should be seekable.
• dynamicSelect: A mode of the current streamer operation.

The method finalizes the reading/writing of data. It should be called after all elements are written or when reading is complete.

method finalizeStreamer

void finalizeStreamer()

This method initializes current streamer object. First parameter should contain the stream or String containing the data to process. All other read/wirte streamer methods will use this given object as a source to read from or as a destination to write to. Second parameter should contain the mode in which this Streamer should be initialized.

method initializeStreamer(aSource: Object; aStreamerMode: StreamerInitialization)

void initializeStreamer(Object aSource, StreamerInitialization aStreamerMode)

Parameters:

• aSource: a data for the streamer to worm with(usually a string or a stream).
• aStreamerMode: an initialization mode of the streamer.

The method checks if specific row value must be included wile streaming data. It can be ommited, if if hasn't been changed. This approach is ussed in Reduced Delta feature of Bin2DataStreamer.

method needIncludeValuesToStream(aOldValue: Object; aNewValue: Object; aIsReducedDelta: Boolean; aIsPK: Boolean; aIncludeOld: ReferenceType<Boolean>; aIncludeNew: ReferenceType<Boolean>): Boolean

Boolean needIncludeValuesToStream(Object aOldValue, Object aNewValue, Boolean aIsReducedDelta, Boolean aIsPK, ReferenceType<Boolean> aIncludeOld, ReferenceType<Boolean> aIncludeNew)

Parameters:

• aOldValue: An original field value.
• aNewValue: A new field value.
• aIsReducedDelta: A flag defines whether or not the delta should be reduced.
• aIsPK: The flag used to define whether of not the field belongs to the primary key.
• aIncludeOld: out param returns whether or not the original value is supposed to be included.
• aIncludeNew: out param returns whether or not the new value is supposed to be included.

Reads the contents of a DataTable from the stream. This method will throw an exception if no DataTable can be found in the stream by the name passed in the first parameter.

Some cases of usage:

  // to load data without schema (in case table has been previously initialized with the schema):
  streamer.readDataTable("Clients", table, <tt>false</tt>, <tt>true</tt>);
  // to initialize the table column structure without loading the ctual data:
  streamer.readDataTable("Clients", table, <tt>true</tt>, <tt>false</tt>);

method readDataTable(aDataTableName: String; aDestination: DataTable; aApplySchema: Boolean; aLoadRecords: Boolean)

void readDataTable(String aDataTableName, DataTable aDestination, Boolean aApplySchema, Boolean aLoadRecords)

Parameters:

• aDataTableName: A name of the data table to be read.
• aDestination: A data table object to fill with tha data.
• aApplySchema: The flag defines, if a Schema should be applied to the given table.
• aLoadRecords: The flag defines, if method should load data for the table.

The method reads the schema for the given table name and returns it.

method readDataTableSchema(aDataTableName: String): SchemaDataTable

SchemaDataTable readDataTableSchema(String aDataTableName)

Parameters:

• aDataTableName: A name of the data table.

The method returns a delta from the provided source. If there is no delta by the name passed it will throw an exception.

method readDelta(aDestination: Delta)

void readDelta(Delta aDestination)

Parameters:

• aDestination: A delta object to be filled.

The method creates a new Delta object using the given Schema and fills it from the source associated with the streamer.

method readDelta(aSchema: Schema; aTableName: String): Delta

Delta readDelta(Schema aSchema, String aTableName)

Parameters:

• aSchema: A schema for a new delta.
• aTableName: A table name, that is used to find delta's data in the streamer's source.

The method writes a DataTable to the streamer destination. This method will throw an exception if a DataTable by the same name already exists in the stream.

method writeDataTable(aTable: DataTable; aTableSchema: SchemaDataTable; aMaxRecords: Integer; aIncludeSchema: Boolean)

void writeDataTable(DataTable aTable, SchemaDataTable aTableSchema, Integer aMaxRecords, Boolean aIncludeSchema)

Parameters:

• aTable: A data table to stream.
• aTableSchema: A data table's schema to use while streaming.
• aMaxRecords: A number of maximum table records the server supposed to send back to the client.
• aIncludeSchema: The flag defines wheter or not server should include table schema in response.

The method creates Delta from the given data table and writes it to the streamer destination. If there is already a delta with this name it will throw an exception.

method writeDelta(aDataTable: DataTable; aDynamicSelect: Boolean): Delta

Delta writeDelta(DataTable aDataTable, Boolean aDynamicSelect)

Parameters:

• aDataTable: A data table to creade delta from.
• aDynamicSelect: A flag that defines whether or not stremaer should use a Dynamic Select feature while streaming the delta.

The method streams the gived delta considering usage of Dynamic Select feature.

method writeDelta(aDelta: Delta; aDynamicSelect: Boolean)

void writeDelta(Delta aDelta, Boolean aDynamicSelect)

Parameters:

• aDelta: A delta to be streamed.
• aDynamicSelect: A flag defines whether or not the streamer should use Dynamic Select feature while writing the delta.