org.geon

Class DatabaseQuery

java.lang.Object

ptolemy.kernel.util.NamedObj

ptolemy.kernel.InstantiableNamedObj

ptolemy.kernel.Entity<T>

ptolemy.kernel.ComponentEntity<T>

ptolemy.actor.AtomicActor<TypedIOPort>

ptolemy.actor.TypedAtomicActor

org.geon.DatabaseAccessor

org.geon.DatabaseQuery

All Implemented Interfaces:

java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, TypedActor, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

Direct Known Subclasses:

GEONDatabaseResource

public class DatabaseQuery
extends DatabaseAccessor

This actor performs database queries against a specific database. It accepts a string query and a database connection reference as inputs. The actor produces the output of the query in the user's selected output format, specified by the outputType parameter, either as an XML, Record, string or a in a relational form with no metadata. The user can also specify whether to broadcast each row at a time or the whole result at once.

Since:

Ptolemy II 3.0.2

Author:

Efrat Jaeger

Nested Class Summary

Nested classes/interfaces inherited from class ptolemy.kernel.Entity

Entity.ContainedObjectsIterator

Field Summary

Fields

Modifier and Type	Field and Description
protected QBTableauFactory	_qbTableauFactory Query builder tableau factory.
StringAttribute	_schemaAttr The schema of the database.
protected DSSchemaIFace	_schemaDef Schema definition interface, used by the query builder
StringAttribute	_sqlAttr Hidden variable containing the xml representation of the query as returned by the query builder.
Parameter	lowerColumnNames If true, column names are converted to lower-case.
Parameter	outputEachRowSeparately Specify whether to display the complete result at once or each row separately.
StringParameter	outputType The output format: XML, Record or String or a relational string with no metadata information.
PortParameter	query An input query string.
TypedIOPort	queryValues Value(s) to use in a prepared statement query.
TypedIOPort	result The query result.

Fields inherited from class org.geon.DatabaseAccessor

_db, dbcon, dbconTokenConsumptionRate, dbParams

Fields inherited from class ptolemy.actor.TypedAtomicActor

_typesValid

Fields inherited from class ptolemy.actor.AtomicActor

_actorFiringListeners, _initializables, _notifyingActorFiring, _stopRequested

Fields inherited from class ptolemy.kernel.util.NamedObj

_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _deferChangeRequests, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS

Fields inherited from interface ptolemy.actor.Executable

COMPLETED, NOT_READY, STOP_ITERATING

Constructor Summary

Constructors

Constructor and Description
DatabaseQuery(CompositeEntity container, java.lang.String name) Construct an actor with the given container and name.

Method Summary

Modifier and Type	Method and Description
void	attributeChanged(Attribute attribute) Determine the output format
java.lang.Object	clone(Workspace workspace) Clone the actor into the specified workspace.
void	connectionsChanged(Port port) Try to set the database schema once the database connection port has been connected.
void	fire() Consume a query and a database connection reference.
boolean	postfire() Takes care of halting the execution in case the query is not updated from a port and hasn't changed.
void	preinitialize() Read the outputType parameter and set output type accordingly.
void	wrapup() Close the connection if open.

Methods inherited from class org.geon.DatabaseAccessor

_setPreparedStatementValue, getConnection, initialize

Methods inherited from class ptolemy.actor.TypedAtomicActor

_containedTypeConstraints, _customTypeConstraints, _defaultTypeConstraints, _fireAt, _fireAt, attributeTypeChanged, clone, isBackwardTypeInferenceEnabled, newPort, typeConstraintList, typeConstraints

Methods inherited from class ptolemy.actor.AtomicActor

_actorFiring, _actorFiring, _declareDelayDependency, addActorFiringListener, addInitializable, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, prefire, pruneDependencies, recordFiring, removeActorFiringListener, removeDependency, removeInitializable, setContainer, stop, stopFire, terminate

Methods inherited from class ptolemy.kernel.ComponentEntity

_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName

Methods inherited from class ptolemy.kernel.Entity

_addPort, _description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName

Methods inherited from class ptolemy.kernel.InstantiableNamedObj

_setParent, exportMoML, getChildren, getElementName, getParent, getPrototypeList, isClassDefinition, isWithinClassDefinition

Methods inherited from class ptolemy.kernel.util.NamedObj

_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _containedDecorators, _copyChangeRequestList, _debug, _debug, _debug, _debug, _debug, _executeChangeRequests, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _notifyHierarchyListenersAfterChange, _notifyHierarchyListenersBeforeChange, _propagateValue, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, addHierarchyListener, attributeDeleted, attributeList, attributeList, decorators, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttributes, getChangeListeners, getClassName, getDecoratorAttribute, getDecoratorAttributes, getDerivedLevel, getDerivedList, getDisplayName, getFullName, getModelErrorHandler, getName, getName, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, lazyContainedObjectsIterator, message, notifyOfNameChange, propagateValue, propagateValues, removeAttribute, removeChangeListener, removeDebugListener, removeHierarchyListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, validateSettables, workspace

Methods inherited from class java.lang.Object

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

Methods inherited from interface ptolemy.actor.Actor

createReceivers, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, newReceiver, outputPortList

Methods inherited from interface ptolemy.actor.Executable

isFireFunctional, isStrict, iterate, prefire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, removeInitializable

Methods inherited from interface ptolemy.kernel.util.Nameable

description, getContainer, getDisplayName, getFullName, getName, getName, setName

Methods inherited from interface ptolemy.kernel.util.Derivable

getDerivedLevel, getDerivedList, propagateValue

Field Detail

outputType

public StringParameter outputType

The output format: XML, Record or String or a relational string with no metadata information.

outputEachRowSeparately

public Parameter outputEachRowSeparately

Specify whether to display the complete result at once or each row separately.

query

public PortParameter query

An input query string. Can use ? to denote parameters in the query, and specify the values queryValues.

result

public TypedIOPort result

The query result.

_sqlAttr

public StringAttribute _sqlAttr

Hidden variable containing the xml representation of the query as returned by the query builder.

_schemaAttr

public StringAttribute _schemaAttr

The schema of the database.

lowerColumnNames

public Parameter lowerColumnNames

If true, column names are converted to lower-case.

queryValues

public TypedIOPort queryValues

Value(s) to use in a prepared statement query. Must be either a single token, or an array. If an array, either the size of the array must be the same as the number of ? in the query, or there is only one ? in the query. In the latter case, the ? in the query is repeated the same number of times as the size of the array.

_qbTableauFactory

protected QBTableauFactory _qbTableauFactory

Query builder tableau factory.

_schemaDef

protected DSSchemaIFace _schemaDef

Schema definition interface, used by the query builder

Constructor Detail

DatabaseQuery

public DatabaseQuery(CompositeEntity container,
                     java.lang.String name)
              throws NameDuplicationException,
                     IllegalActionException

Construct an actor with the given container and name.

Parameters:

container - The container.

name - The name of this actor.

Throws:

IllegalActionException - If the actor cannot be contained by the proposed container.

NameDuplicationException - If the container already has an actor with this name.

Method Detail

attributeChanged

public void attributeChanged(Attribute attribute)
                      throws IllegalActionException

Determine the output format

Overrides:

attributeChanged in class NamedObj

Parameters:

attribute - The attribute that changed.

Throws:

IllegalActionException - If the output type is not recognized.

clone

public java.lang.Object clone(Workspace workspace)
                       throws java.lang.CloneNotSupportedException

Description copied from class: TypedAtomicActor

Clone the actor into the specified workspace.

Overrides:

clone in class TypedAtomicActor

Parameters:

workspace - The workspace for the new object.

Returns:

A new actor.

Throws:

java.lang.CloneNotSupportedException - If a derived class contains an attribute that cannot be cloned.

See Also:

NamedObj.exportMoML(Writer, int, String), NamedObj.setDeferringChangeRequests(boolean)

connectionsChanged

public void connectionsChanged(Port port)

Try to set the database schema once the database connection port has been connected.

Overrides:

connectionsChanged in class AtomicActor<TypedIOPort>

Parameters:

port - The port that has connection changes.

fire

public void fire()
          throws IllegalActionException

Consume a query and a database connection reference. Compute the query result according to the specified output format.

Specified by:

fire in interface Executable

Overrides:

fire in class DatabaseAccessor

Throws:

IllegalActionException - If there is no director.

postfire

public boolean postfire()
                 throws IllegalActionException

Takes care of halting the execution in case the query is not updated from a port and hasn't changed.

Specified by:

postfire in interface Executable

Overrides:

postfire in class AtomicActor<TypedIOPort>

Returns:

True if execution can continue into the next iteration.

Throws:

IllegalActionException - Not thrown in this base class.

preinitialize

public void preinitialize()
                   throws IllegalActionException

Read the outputType parameter and set output type accordingly.

Specified by:

preinitialize in interface Initializable

Overrides:

preinitialize in class AtomicActor<TypedIOPort>

Throws:

IllegalActionException - If the file or URL cannot be opened, or if the first line cannot be read.

wrapup

public void wrapup()
            throws IllegalActionException

Description copied from class: DatabaseAccessor

Close the connection if open.

Specified by:

wrapup in interface Initializable

Overrides:

wrapup in class DatabaseAccessor

Throws:

IllegalActionException - Not thrown in this base class.