org.drools.reteoo
Class ObjectTypeNode

java.lang.Object
  org.drools.common.BaseNode
      org.drools.reteoo.ObjectSource
          org.drools.reteoo.ObjectTypeNode

All Implemented Interfaces:

java.io.Serializable, NetworkNode, NodeMemory, ObjectSink

public class ObjectTypeNode
extends ObjectSource
implements ObjectSink, java.io.Serializable, NodeMemory

ObjectTypeNodes are responsible for filtering and propagating the matching fact assertions propagated from the Rete node using ObjectType interface.

The assert and retract methods do not attempt to filter as this is the role of the Rete node which builds up a cache of matching ObjectTypdeNodess for each asserted object, using the matches(Object object) method. Incorrect propagation in these methods is not checked and will result in ClassCastExpcections later on in the network.

Filters Objects coming from the Rete using a ObjectType semantic module.

Author:

Mark Proctor, Bob McWhirter

See Also:

ObjectType, Rete, Serialized Form

Field Summary

Fields inherited from class org.drools.reteoo.ObjectSource

objectSource, sink

Fields inherited from class org.drools.common.BaseNode

id

Constructor Summary

ObjectTypeNode(int id, ObjectType objectType, BuildContext context)
Construct given a semantic ObjectType and the provided unique id.

Method Summary

protected void	addObjectSink(ObjectSink objectSink) Adds the ObjectSink so that it may receive FactHandleImpl propagated from this ObjectSource.
void	assertObject(InternalFactHandle handle, PropagationContext context, InternalWorkingMemory workingMemory) Propagate the FactHandleimpl through the Rete network.
void	attach() Rete needs to know that this ObjectTypeNode has been added
void	attach(InternalWorkingMemory[] workingMemories)
java.lang.Object	createMemory(RuleBaseConfiguration config) Creates memory for the node using PrimitiveLongMap as its optimised for storage and reteivals of Longs.
boolean	equals(java.lang.Object object)
ObjectType	getObjectType() Retrieve the semantic ObjectType differentiator.
int	hashCode() Uses he hashCode() of the underlying ObjectType implementation.
boolean	isAssignableFrom(java.lang.Object object)
boolean	isObjectMemoryEnabled()
boolean	matches(java.lang.Object object) Tests the provided object to see if this ObjectTypeNode can receive the object for assertion and retraction propagations.
void	remove(RuleRemovalContext context, BaseNode node, InternalWorkingMemory[] workingMemories) Removes the node from teh network.
protected void	removeObjectSink(ObjectSink objectSink) Removes the ObjectSink
void	retractObject(InternalFactHandle handle, PropagationContext context, InternalWorkingMemory workingMemory) Retract the FactHandleimpl from the Rete network.
void	setObjectMemoryEnabled(boolean objectMemoryEnabled)
java.lang.String	toString()
void	updateSink(ObjectSink sink, PropagationContext context, InternalWorkingMemory workingMemory)

Methods inherited from class org.drools.reteoo.ObjectSource

getSinkPropagator, isInUse

Methods inherited from class org.drools.common.BaseNode

getId

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.drools.common.NodeMemory

getId

Constructor Detail

ObjectTypeNode

public ObjectTypeNode(int id,
                      ObjectType objectType,
                      BuildContext context)

Construct given a semantic ObjectType and the provided unique id. All ObjectTypdeNode have node memory.

Parameters:

id - The unique id for the node.

objectType - The semantic object-type differentiator.

Method Detail

getObjectType

public ObjectType getObjectType()

Retrieve the semantic ObjectType differentiator.

Returns:

The semantic ObjectType differentiator.

matches

public boolean matches(java.lang.Object object)

Tests the provided object to see if this ObjectTypeNode can receive the object for assertion and retraction propagations.

Parameters:

object -

Returns:

boolean value indicating whether the ObjectTypeNode can receive the object.

isAssignableFrom

public boolean isAssignableFrom(java.lang.Object object)

assertObject

public void assertObject(InternalFactHandle handle,
                         PropagationContext context,
                         InternalWorkingMemory workingMemory)

Propagate the FactHandleimpl through the Rete network. All FactHandleImpl should be remembered in the node memory, so that later runtime rule attachmnents can have the matched facts propagated to them.

Specified by:

assertObject in interface ObjectSink

Parameters:

handle - The fact handle.

object - The object to assert.

workingMemory - The working memory session.

retractObject

public void retractObject(InternalFactHandle handle,
                          PropagationContext context,
                          InternalWorkingMemory workingMemory)

Retract the FactHandleimpl from the Rete network. Also remove the FactHandleImpl from the node memory.

Specified by:

retractObject in interface ObjectSink

Parameters:

handle - The fact handle.

object - The object to assert.

workingMemory - The working memory session.

updateSink

public void updateSink(ObjectSink sink,
                       PropagationContext context,
                       InternalWorkingMemory workingMemory)

Specified by:

updateSink in class ObjectSource

attach

public void attach()

Rete needs to know that this ObjectTypeNode has been added

Specified by:

attach in class BaseNode

attach

public void attach(InternalWorkingMemory[] workingMemories)

Specified by:

attach in class BaseNode

remove

public void remove(RuleRemovalContext context,
                   BaseNode node,
                   InternalWorkingMemory[] workingMemories)

Description copied from class: BaseNode

Removes the node from teh network. Usually from the parent ObjectSource or TupleSource

Specified by:

remove in class BaseNode

createMemory

public java.lang.Object createMemory(RuleBaseConfiguration config)

Creates memory for the node using PrimitiveLongMap as its optimised for storage and reteivals of Longs. However PrimitiveLongMap is not ideal for spase data. So it should be monitored incase its more optimal to switch back to a standard HashMap.

Specified by:

createMemory in interface NodeMemory

isObjectMemoryEnabled

public boolean isObjectMemoryEnabled()

Specified by:

isObjectMemoryEnabled in interface ObjectSink

setObjectMemoryEnabled

public void setObjectMemoryEnabled(boolean objectMemoryEnabled)

Specified by:

setObjectMemoryEnabled in interface ObjectSink

toString

public java.lang.String toString()

Overrides:

toString in class BaseNode

hashCode

public int hashCode()

Uses he hashCode() of the underlying ObjectType implementation.

Overrides:

hashCode in class BaseNode

equals

public boolean equals(java.lang.Object object)

Overrides:

equals in class java.lang.Object

addObjectSink

protected void addObjectSink(ObjectSink objectSink)

Description copied from class: ObjectSource

Adds the ObjectSink so that it may receive FactHandleImpl propagated from this ObjectSource.

Overrides:

addObjectSink in class ObjectSource

Parameters:

objectSink - The ObjectSink to receive propagated FactHandleImpl.

removeObjectSink

protected void removeObjectSink(ObjectSink objectSink)

Description copied from class: ObjectSource

Removes the ObjectSink

Overrides:

removeObjectSink in class ObjectSource

Parameters:

objectSink - The ObjectSink to remove