com.goldencode.p2j.persist.orm

Class Query

java.lang.Object

com.goldencode.p2j.persist.orm.Query

public class Query
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Query.QueryParams Parameters' data holder

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.function.Consumer<Query>	cache Caching lambda
private boolean	containsErrorHandling Flag indicating that the query contains error handling
private int	firstResult The index of the first matching results accepted by the (SELECT) query.
private java.lang.String	fql The query as a FQL (FWD Query Language) statement.
private boolean	lazyMode Flag accepted by the Select query.
private boolean	lockTableRead Flag indicating that the query reads from _Lock VST
private int	maxResults The maximum number of results accepted by the (SELECT) query.
private int	paramCount The number of parameter as detected after parsing the FQL statement.
private Query.QueryParams	params Query parameters' data
private static NanoTimer	QUERY_PARSE Instrumentation for createSqlQuery(com.goldencode.p2j.persist.dialect.Dialect, com.goldencode.p2j.persist.Database).
private DataRelation	relation The recursive DATA-RELATION the query is to FILL for
private java.util.ArrayList<RowStructure>	rowStructure The expected structure of a query, as generated by the FqlToSqlConverter.
private SQLQuery	sqlQuery The cached SQL query.
private boolean	userTableStatRead Flag indicating that the query reads from _UserTableStat VST
private boolean	wasRewritten Flags a query which was re-written

Constructor Summary

Constructors

Constructor and Description
Query(java.util.function.Consumer<Query> cache, java.lang.String fql) Creates a new Query object.

Method Summary

Modifier and Type	Method and Description
private SQLQuery	createSqlQuery(Dialect dialect, Database db) Creates the delegating SQL query.
int	executeUpdate(Session session) Converts the fql statement to SQL and applies the eventual parameters then execute the update SQL query.
DataRelation	getDataRelation() Get the recursive DATA-RELATION the query is to FILL for.
(package private) static Dialect	getDialect(Session session) Get the dialect of the database the session is connected to.
private static java.lang.String	getSchema(Session session) Get the schema of the database the session is connected to.
(package private) SQLQuery	getSqlQuery() Get the SQLQuery object created by this object.
<T> java.util.List<T>	list(Session session) Returns a list of rows of type <T> by converting the fql to SQL and executing the query against the SQL server.
<T> java.util.List<T>	list(Session session, boolean hydrateRecords) Returns a list of rows of type <T> by converting the fql to SQL and executing the query against the SQL server.
<T> ScrollableResults<T>	scroll(Session session, int scrollMode) Returns a scrollable list of rows of type <T> by converting the fql to SQL and executing the query against the SQL server.
void	setDataRelation(DataRelation relation) Set the recursive DATA-RELATION the query is to FILL for.
void	setFirstResult(int firstResult) Configures the index of the first row to be returned by this query.
void	setLazyMode(boolean lazyMode) Setter for the lazyMode flag.
void	setMaxResults(int maxResults) Configures the maximum number of rows returned by this query.
void	setParameter(int index, java.lang.Object arg) Sets the value of a parameter for this query.
<T> T	uniqueResult(Session session) Returns an unique row of type <T> by converting the fql to SQL and executing the query against the SQL server.

Methods inherited from class java.lang.Object

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

Field Detail

QUERY_PARSE

private static final NanoTimer QUERY_PARSE

Instrumentation for createSqlQuery(com.goldencode.p2j.persist.dialect.Dialect, com.goldencode.p2j.persist.Database).

cache

private final java.util.function.Consumer<Query> cache

Caching lambda

fql

private final java.lang.String fql

The query as a FQL (FWD Query Language) statement.

wasRewritten

private boolean wasRewritten

Flags a query which was re-written

userTableStatRead

private boolean userTableStatRead

Flag indicating that the query reads from _UserTableStat VST

lockTableRead

private boolean lockTableRead

Flag indicating that the query reads from _Lock VST

containsErrorHandling

private boolean containsErrorHandling

Flag indicating that the query contains error handling

maxResults

private int maxResults

The maximum number of results accepted by the (SELECT) query. Used with firstResult to configure result pagination.

lazyMode

private boolean lazyMode

Flag accepted by the Select query. If it is set to true, then the query will be executed in a lazy manner. By default, queries are executed in a preselect manner.

firstResult

private int firstResult

The index of the first matching results accepted by the (SELECT) query. Used in combination with firstResult to configure result pagination.

paramCount

private int paramCount

The number of parameter as detected after parsing the FQL statement.

params

private final Query.QueryParams params

Query parameters' data

sqlQuery

private SQLQuery sqlQuery

The cached SQL query.

relation

private DataRelation relation

The recursive DATA-RELATION the query is to FILL for

rowStructure

private java.util.ArrayList<RowStructure> rowStructure

The expected structure of a query, as generated by the FqlToSqlConverter. The content is not very explicit for the moment, only the DMO and the number of fields. If more info is needed ity can be added in subsequent developonet rounds.

Constructor Detail

Query

public Query(java.util.function.Consumer<Query> cache,
             java.lang.String fql)

Creates a new Query object.

Parameters:

cache - cache query lambda

fql - The query as a FQL (FWD Query Language) statement.

Method Detail

setMaxResults

public void setMaxResults(int maxResults)

Configures the maximum number of rows returned by this query. Depending on the SQL dialect from the session, the value is injected as the parameter of SQL limit clause.

Parameters:

maxResults - The maximum number of results accepted by the (SELECT) query.

setLazyMode

public void setLazyMode(boolean lazyMode)

Setter for the lazyMode flag. Note: this method should only be called if the Query executed is a Select.

Parameters:

lazyMode - If true, the Query will be executed in a lazy manner.

setFirstResult

public void setFirstResult(int firstResult)

Configures the index of the first row to be returned by this query. Depending on the SQL dialect from the session, the value is injected as the parameter of SQL limit clause.

Parameters:

firstResult - The index of teh first matching results accepted by the (SELECT) query.

setParameter

public void setParameter(int index,
                         java.lang.Object arg)

Sets the value of a parameter for this query. This is done before parsing the HQL so the index of the parameter is NOT checked.

Parameters:

index - The index of the parameter to be set (0-base).

arg - The parameter value.

scroll

public <T> ScrollableResults<T> scroll(Session session,
                                       int scrollMode)
                                throws PersistenceException

Returns a scrollable list of rows of type <T> by converting the fql to SQL and executing the query against the SQL server.

Type Parameters:

T - The type of the rows returned in the list.

Parameters:

session - The Session to be used.

scrollMode - The scroll mode.

Returns:

A scrollable list of rows of type <T> from SQL server, as specified by the fql query.

Throws:

PersistenceException - when an error occurred while performing the requested operations.

uniqueResult

public <T> T uniqueResult(Session session)
                   throws UniqueResultException,
                          PersistenceException

Returns an unique row of type <T> by converting the fql to SQL and executing the query against the SQL server.

Type Parameters:

T - The type of the row to be returned.

Parameters:

session - The Session to be used.

Returns:

A row of type <T> from SQL server, as specified by the fql query.

Throws:

UniqueResultException - if the result set contains not an exactly one row.

PersistenceException - when an error occurred while performing the requested operations.

list

public <T> java.util.List<T> list(Session session)
                           throws PersistenceException

Returns a list of rows of type <T> by converting the fql to SQL and executing the query against the SQL server. The returned list will contain a set of hydrated Record objects.

Type Parameters:

T - The type of the rows returned in the list.

Parameters:

session - The Session to be used.

Returns:

A list of rows of type <T> from SQL server, as specified by the fql query.

Throws:

PersistenceException - when an error occurred while performing the requested operations.

list

public <T> java.util.List<T> list(Session session,
                                  boolean hydrateRecords)
                           throws PersistenceException

Returns a list of rows of type <T> by converting the fql to SQL and executing the query against the SQL server. According to last parameter, the returning list can contain hydrated Record objects (if hydrateRecords is true) or plain Java wrappers (driver specific, which includes: Integer, String, BigDecimal, etc.)

Type Parameters:

T - The type of the rows returned in the list.

Parameters:

session - The Session to be used.

hydrateRecords - If true the result is interpreted as legacy records and will be hydrated. Otherwise, the returned List contains an array for each row.

Returns:

A list of rows of type <T> from SQL server, as specified by the fql query.

Throws:

PersistenceException - when an error occurred while performing the requested operations.

executeUpdate

public int executeUpdate(Session session)
                  throws PersistenceException

Converts the fql statement to SQL and applies the eventual parameters then execute the update SQL query. When finished with success returns the number of affected columns.

Parameters:

session - The Session to be used.

Returns:

The number of affected rows by the statement.

Throws:

PersistenceException - when an error occurred while performing the requested operations.

getSqlQuery

SQLQuery getSqlQuery()

Get the SQLQuery object created by this object. If invoked before the query is executed, null is returned.

Returns:

SQL query object or null if invoked too early.

createSqlQuery

private SQLQuery createSqlQuery(Dialect dialect,
                                Database db)
                         throws PersistenceException

Creates the delegating SQL query. The fql statement is converted to SQL and a SQLQuery is created from current session. The pagination are configured and the eventual parameters are set. When finished, the SQL query is returned.

Parameters:

dialect - The Dialect to be used in conversion.

db - The database. This is used to unambiguate short-names entities.

Returns:

The SQL query as described above.

Throws:

PersistenceException - on error occurred while creating the query or setting the parameters.

getDialect

static Dialect getDialect(Session session)

Get the dialect of the database the session is connected to.

Parameters:

session - The session to be investigated.

Returns:

the dialect of the database the session is connected to.

getSchema

private static java.lang.String getSchema(Session session)

Get the schema of the database the session is connected to.

Parameters:

session - The session to be investigated.

Returns:

the schema of the database the session is connected to.

getDataRelation

public DataRelation getDataRelation()

Get the recursive DATA-RELATION the query is to FILL for.

Returns:

the recursive DATA-RELATION the query is to FILL for

setDataRelation

public void setDataRelation(DataRelation relation)

Set the recursive DATA-RELATION the query is to FILL for.

Parameters:

relation - the recursive DATA-RELATION the query is to FILL for