com.goldencode.p2j.persist.orm

Class Persister

java.lang.Object

com.goldencode.p2j.persist.orm.Persister

class Persister
extends java.lang.Object

A class which processes database inserts, updates, and deletes for data model objects (DMOs), using record metadata defined by the DMO's interface (in annotations).

The methods in this class are highly dependent upon the order of the elements in BaseRecord's internal data array, which are laid out in a well-known order.

See Also:

Loader

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	Persister.UpdateInfo This class acts both as key and value for storing the information on a cached UPDATE set of statements.

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	allowDBUniqueCheck Flag (only for temporary databases) that marks if the index server-validation was skipped and it should be done by H2.
private org.h2.embedded.DirectAccessDriver	directAccessDriver The DirectAccessDriver for H2.
private static CentralLogger	LOG Logger
private Session	session Active database session
private static ExpiryCache<Persister.UpdateInfo,Persister.UpdateInfo>	updateCache Cache of FQL strings, with or without max results and start offsets, to queries.

Constructor Summary

Constructors

Constructor and Description
Persister(Session session) Constructor.

Method Summary

Modifier and Type	Method and Description
(package private) <T extends BaseRecord> int	bulkInsert(java.util.List<T> records) Insert the data of the given list of DMOs into its corresponding primary table and any secondary tables in the database.
private void	closePreparedStatements(java.sql.PreparedStatement[] ps) Close the given prepared statements.
(package private) static java.lang.String[]	composeDeleteStatements(java.lang.String[] tables) Compose the statements needed to delete a DMO and all of its normalized extent field data.
(package private) static java.lang.String[]	composeInsertStatements(java.lang.String table, PropertyMeta[] allPropMeta, boolean temp) Compose the SQL statements used to insert a single DMO into the database.
(package private) boolean	delete(BaseRecord dmo) Delete the record(s) associated with the given DMO from the database.
(package private) boolean	delete(java.lang.Class<? extends BaseRecord> dmoClass, java.lang.Long id) Delete the record(s) associated with the given DMO from the database.
private int	executeBatch(java.sql.PreparedStatement ps) Execute a batch of commands using the given prepared statement.
(package private) boolean	getAllowDBUniqueCheck() Getter for the allowDBUniqueCheck field.
static void	initializeCache() Initializes the cache using CacheManager.
(package private) <T extends BaseRecord> int	insert(T dmo) Insert the data of the given DMO into its corresponding primary table and any secondary tables in the database.
private <T extends BaseRecord> int	insert(T dmo, java.sql.PreparedStatement[] preparedStatements, boolean bulk) Insert the data of the given DMO into its corresponding primary table and any secondary tables in the database.
private <T extends BaseRecord> java.sql.PreparedStatement[]	prepareInsertStatements(T dmo) Prepare the insert statements for the table(s) associated with the given DMO.
(package private) boolean	setAllowDBUniqueCheck(boolean value) Setter for the allowDBUniqueCheck field.
(package private) <T extends BaseRecord> void	update(T dmo) Saves changes of the dmo by executing one or more UPDATE statements.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final CentralLogger LOG

Logger

updateCache

private static ExpiryCache<Persister.UpdateInfo,Persister.UpdateInfo> updateCache

Cache of FQL strings, with or without max results and start offsets, to queries.

session

private final Session session

Active database session

directAccessDriver

private org.h2.embedded.DirectAccessDriver directAccessDriver

The DirectAccessDriver for H2.

allowDBUniqueCheck

private boolean allowDBUniqueCheck

Flag (only for temporary databases) that marks if the index server-validation was skipped and it should be done by H2.

Constructor Detail

Persister

Persister(Session session)

Constructor.

Parameters:

session - Active database associated with this persister.

Method Detail

initializeCache

public static void initializeCache()

Initializes the cache using CacheManager. Only one cache is used, so there is no need for a discriminator. The default value of the cache is used when there is no size available from the configuration.

composeInsertStatements

static java.lang.String[] composeInsertStatements(java.lang.String table,
                                                  PropertyMeta[] allPropMeta,
                                                  boolean temp)

Compose the SQL statements used to insert a single DMO into the database. This will include a statement to insert the primary record into the primary table, followed by zero or more statements to insert multiple records into secondary tables for the DMO's extent fields (if any). Denormalized extent fields are treated like scalar fields.

Parameters:

table - SQL name of the primary table. The naming convention assumed for secondary tables is: <primary_table>__<extent_size>.

allPropMeta - Array of PropertyMeta objects in their natural order.

temp - Pass true for _temp DMOs. In this case the insert statement will be build with the mandatory _multiplex field for temp-tables.

Returns:

An array of one or more SQL statements as described above.

See Also:

PropertyMeta.compareTo(PropertyMeta)

composeDeleteStatements

static java.lang.String[] composeDeleteStatements(java.lang.String[] tables)

Compose the statements needed to delete a DMO and all of its normalized extent field data. The order of the statements is inverted from the order of the table names for the DMO, so that foreign records are deleted before the primary record they reference.

Parameters:

tables - Table names for this DMO, primary first.

Returns:

An array of delete statements which can be executed in order to delete a single DMO record from the database.

getAllowDBUniqueCheck

boolean getAllowDBUniqueCheck()

Getter for the allowDBUniqueCheck field.

Returns:

Boolean The value of the allowDBUniqueCheck field.

setAllowDBUniqueCheck

boolean setAllowDBUniqueCheck(boolean value)

Setter for the allowDBUniqueCheck field.

Parameters:

value - The value which will be assigned to the allowDBUniqueCheck field.

Returns:

The old value set for allow DB unique check.

bulkInsert

<T extends BaseRecord> int bulkInsert(java.util.List<T> records)
                               throws PersistenceException

Insert the data of the given list of DMOs into its corresponding primary table and any secondary tables in the database. Use SQL batching if the JDBC driver supports it, otherwise, submit each insert statement individually. The DMOs must all be of the same type.

This method must be called within a transaction for the data to be preserved. Scalar data is inserted first into the primary table, followed by normalized extent field data, if any, into any secondary tables.

Parameters:

records - List of one or more DMO instances whose data is to be inserted into the database.

Returns:

The count of records (primary and secondary) successfully inserted into the database.

Throws:

PersistenceException - if an error occurs accessing the database.

insert

<T extends BaseRecord> int insert(T dmo)
                           throws PersistenceException

Insert the data of the given DMO into its corresponding primary table and any secondary tables in the database. This method must be called within a transaction for the data to be preserved. Scalar data is inserted first into the primary table, followed by normalized extent field data, if any, into any secondary tables. Batch execution is used if supported by the JDBC driver.

Parameters:

dmo - DMO instance whose data is to be inserted into the database.

Returns:

The count of records (primary and secondary) successfully inserted into the database.

Throws:

PersistenceException - if an error occurs accessing the database.

delete

boolean delete(BaseRecord dmo)
        throws PersistenceException

Delete the record(s) associated with the given DMO from the database. Secondary (foreign) records, if any, are deleted first, then the primary record.

Parameters:

dmo - DMO whose records are to be deleted.

Throws:

PersistenceException - if there is a database error.

delete

boolean delete(java.lang.Class<? extends BaseRecord> dmoClass,
               java.lang.Long id)
        throws PersistenceException

Delete the record(s) associated with the given DMO from the database. Secondary (foreign) records, if any, are deleted first, then the primary record.

Parameters:

dmoClass - DMO implementation class.

id - Primary key of record to be deleted.

Throws:

PersistenceException - if there is a database error.

update

<T extends BaseRecord> void update(T dmo)
                            throws PersistenceException

Saves changes of the dmo by executing one or more UPDATE statements.

Type Parameters:

T - The type(class) of the Record.

Parameters:

dmo - The object whose changes will be flushed to database.

Throws:

PersistenceException - In case of any issue encountered in the process.

insert

private <T extends BaseRecord> int insert(T dmo,
                                          java.sql.PreparedStatement[] preparedStatements,
                                          boolean bulk)
                                   throws PersistenceException

Insert the data of the given DMO into its corresponding primary table and any secondary tables in the database. This method must be called within a transaction for the data to be preserved. Scalar data is inserted first into the primary table, followed by normalized extent field data, if any, into any secondary tables. Batch execution is used if supported by the JDBC driver.

Parameters:

dmo - DMO instance whose data is to be inserted into the database.

preparedStatements - Array of prepared, insert statements corresponding with dmo's primary table and any secondary tables for normalized extent fields, in ascending order of extent.

bulk - true if this insert is part of a bulk insert; false if it represents the insert of a single record. If the former, the caller is responsible for executing the batches of statements this method prepares; if the latter, this method will execute the batch of statements directly.

Returns:

The count of records (primary and secondary) successfully inserted into the database.

Throws:

PersistenceException - if an error occurs accessing the database.

prepareInsertStatements

private <T extends BaseRecord> java.sql.PreparedStatement[] prepareInsertStatements(T dmo)
                                                                             throws PersistenceException

Prepare the insert statements for the table(s) associated with the given DMO. There will be one statement for the primary table, plus one per secondary table for normalized extent fields.

Parameters:

dmo - Data model object whose type is used to determine the insert statements to be prepared.

Returns:

An array of prepared insert statements, one for the primary table and the rest (if any) for the secondary, normalized, extent field tables, in ascending order of extent size.

Throws:

PersistenceException - if there is an error preparing the statements.

closePreparedStatements

private void closePreparedStatements(java.sql.PreparedStatement[] ps)
                              throws PersistenceException

Close the given prepared statements.

Parameters:

ps - Array of prepared statements to close.

Throws:

PersistenceException - if there is an error closing the prepared statements.

executeBatch

private int executeBatch(java.sql.PreparedStatement ps)
                  throws java.sql.SQLException

Execute a batch of commands using the given prepared statement.

Parameters:

ps - Prepared statement.

Returns:

The count of rows affected by the batch execution. TODO: handle possible status codes returned by executeBatch()

Throws:

java.sql.SQLException - if a database error occurs.