Class SequenceTable

java.lang.Object

org.datanucleus.store.rdbms.table.AbstractTable

org.datanucleus.store.rdbms.table.TableImpl

org.datanucleus.store.rdbms.valuegenerator.SequenceTable

All Implemented Interfaces:

Table, org.datanucleus.store.schema.table.Table

public class SequenceTable
extends TableImpl

Class defining a table for storing generated values for use with TableGenerator. The table has 2 columns : a primary key String, and a value Long.

Field Summary

Fields

Modifier and Type	Field	Description
private String	fetchStmt
private String	incrementByStmt
private String	insertStmt
private String	nextValColumnName	the next value column name
private JavaTypeMapping	nextValMapping	Mapping for the next value column
private String	sequenceNameColumnName	the sequence column name
private JavaTypeMapping	sequenceNameMapping	Mapping for the sequence name column.

Fields inherited from class AbstractTable

columns, columnsByIdentifier, dba, existsInDatastore, identifier, state, storeMgr, TABLE_STATE_INITIALIZED, TABLE_STATE_INITIALIZED_MODIFIED, TABLE_STATE_NEW, TABLE_STATE_PK_INITIALIZED, TABLE_STATE_VALIDATED

Constructor Summary

Constructors

Constructor	Description
SequenceTable(DatastoreIdentifier identifier, RDBMSStoreManager storeMgr, String seqNameColName, String nextValColName)	Constructor

Method Summary

Modifier and Type	Method	Description
private void	addSequence(String sequenceName, Long nextVal, org.datanucleus.store.connection.ManagedConnection conn)	Method to insert a row in the SequenceTable
JavaTypeMapping	getIdMapping()	Accessor for a mapping for the ID (persistable) for this table.
JavaTypeMapping	getMemberMapping(org.datanucleus.metadata.AbstractMemberMetaData mmd)	Accessor the for the mapping for a field stored in this table
Long	getNextVal(String sequenceName, org.datanucleus.store.connection.ManagedConnection conn, int incrementBy, DatastoreIdentifier tableIdentifier, String columnName, int initialValue)	Accessor for the nextval of a sequence
private void	incrementSequence(String sequenceName, long incrementBy, org.datanucleus.store.connection.ManagedConnection conn)	Method to increment a sequence
void	initialize(org.datanucleus.ClassLoaderResolver clr)	Method to initialise the table.

Methods inherited from class TableImpl

createConstraints, dropConstraints, getExpectedCandidateKeys, getExpectedForeignKeys, getExpectedIndices, getPrimaryKey, getSQLAddCandidateKeyStatements, getSQLAddFKStatements, getSQLCreateIndexStatements, getSQLCreateStatements, getSQLDropStatements, initializeColumnInfoForPrimaryKeyColumns, initializeColumnInfoFromDatastore, logMapping, validate, validateColumns, validateConstraints, validatePrimaryKey

Methods inherited from class AbstractTable

addColumn, addColumnInternal, allowDDLOutput, assertIsInitialized, assertIsInitializedModified, assertIsPKInitialized, assertIsPKUninitialized, assertIsUninitialized, assertIsValidated, create, drop, equals, executeDdlStatement, executeDdlStatementList, exists, getCatalogName, getClassMetaData, getColumn, getColumnForName, getColumnForPosition, getColumns, getDatastoreIdentifierFullyQualified, getDiscriminatorMetaData, getIdentifier, getMemberColumnMappingForEmbeddedMember, getMemberColumnMappingForMember, getMemberColumnMappings, getName, getNumberOfColumns, getSchemaName, getStoreManager, getSurrogateColumn, getSurrogateMapping, getVersionMetaData, hasColumn, hasColumnName, hashCode, isInitialized, isInitializedModified, isPKInitialized, isValidated, postInitialize, preInitialize, tableExistsInDatastore, toString

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

sequenceNameMapping

private JavaTypeMapping sequenceNameMapping

Mapping for the sequence name column.

nextValMapping

private JavaTypeMapping nextValMapping

Mapping for the next value column

insertStmt

private String insertStmt

incrementByStmt

private String incrementByStmt

fetchStmt

private String fetchStmt

sequenceNameColumnName

private String sequenceNameColumnName

the sequence column name

nextValColumnName

private String nextValColumnName

the next value column name

Constructor Details

SequenceTable

public SequenceTable(DatastoreIdentifier identifier,
 RDBMSStoreManager storeMgr,
 String seqNameColName,
 String nextValColName)

Constructor

Parameters:

identifier - Datastore identifier for this table

storeMgr - The RDBMSManager for this datastore

seqNameColName - Name for the "sequence name" column

nextValColName - Name for the "next value" column

Method Details

initialize

public void initialize(org.datanucleus.ClassLoaderResolver clr)

Method to initialise the table.

Parameters:

clr - The ClassLoaderResolver

getIdMapping

public JavaTypeMapping getIdMapping()

Accessor for a mapping for the ID (persistable) for this table.

Returns:

The (persistable) ID mapping.

getNextVal

public Long getNextVal(String sequenceName,
 org.datanucleus.store.connection.ManagedConnection conn,
 int incrementBy,
 DatastoreIdentifier tableIdentifier,
 String columnName,
 int initialValue)
                throws SQLException

Accessor for the nextval of a sequence

Parameters:

sequenceName - The sequence name (the key)

conn - Connection for this datastore.

incrementBy - The amount to increment (from the current value)

tableIdentifier - Identifier for the table being incremented (used when there is no current value)

columnName - Name of the column being incremented (used when there is no current value)

initialValue - Initial value (if not using tableIdentifier/columnName to find the initial value)

Returns:

The next value that should be used

Throws:

SQLException - Thrown when an error occurs in the process.

incrementSequence

private void incrementSequence(String sequenceName,
 long incrementBy,
 org.datanucleus.store.connection.ManagedConnection conn)
                        throws SQLException

Method to increment a sequence

Parameters:

conn - Connection to the datastore

Throws:

SQLException - Thrown when an error occurs incrementing the sequence.

addSequence

private void addSequence(String sequenceName,
 Long nextVal,
 org.datanucleus.store.connection.ManagedConnection conn)
                  throws SQLException

Method to insert a row in the SequenceTable

Parameters:

conn - Connection to the datastore

Throws:

SQLException - Thrown when an error occurs inserting the sequence.

getMemberMapping

public JavaTypeMapping getMemberMapping(org.datanucleus.metadata.AbstractMemberMetaData mmd)

Accessor the for the mapping for a field stored in this table

Parameters:

mmd - MetaData for the field whose mapping we want

Returns:

The mapping