/**
* Copyright 2005 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.common;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import org.drools.RuleBaseConfiguration;
import org.drools.base.evaluators.Operator;
import org.drools.core.util.LeftTupleIndexHashTable;
import org.drools.core.util.LeftTupleList;
import org.drools.core.util.LinkedList;
import org.drools.core.util.LinkedListEntry;
import org.drools.core.util.RightTupleIndexHashTable;
import org.drools.core.util.RightTupleList;
import org.drools.core.util.AbstractHashTable.FieldIndex;
import org.drools.reteoo.BetaMemory;
import org.drools.reteoo.LeftTuple;
import org.drools.reteoo.LeftTupleMemory;
import org.drools.reteoo.RightTupleMemory;
import org.drools.rule.ContextEntry;
import org.drools.rule.UnificationRestriction;
import org.drools.rule.VariableConstraint;
import org.drools.spi.BetaNodeFieldConstraint;
public class SingleBetaConstraints
implements
BetaConstraints {
/**
*
*/
private static final long serialVersionUID = 510l;
private BetaNodeFieldConstraint constraint;
private boolean indexed;
private RuleBaseConfiguration conf;
public SingleBetaConstraints() {
}
public SingleBetaConstraints(final BetaNodeFieldConstraint[] constraint,
final RuleBaseConfiguration conf) {
this( constraint[0],
conf,
false );
}
public SingleBetaConstraints(final BetaNodeFieldConstraint constraint,
final RuleBaseConfiguration conf) {
this( constraint,
conf,
false );
}
public SingleBetaConstraints(final BetaNodeFieldConstraint constraint,
final RuleBaseConfiguration conf,
final boolean disableIndex) {
this.conf = conf;
if ( (disableIndex) || (!conf.isIndexLeftBetaMemory() && !conf.isIndexRightBetaMemory()) ) {
this.indexed = false;
} else {
final int depth = conf.getCompositeKeyDepth();
// Determine if this constraint is indexable
this.indexed = depth >= 1 && isIndexable( constraint );
}
this.constraint = constraint;
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
constraint = (BetaNodeFieldConstraint)in.readObject();
indexed = in.readBoolean();
conf = (RuleBaseConfiguration)in.readObject();
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(constraint);
out.writeBoolean(indexed);
out.writeObject(conf);
}
public static boolean isIndexable(final BetaNodeFieldConstraint constraint) {
if ( constraint instanceof VariableConstraint ) {
final VariableConstraint variableConstraint = (VariableConstraint) constraint;
if ( (!(variableConstraint.getRestriction() instanceof UnificationRestriction )) ) {
return (variableConstraint.getEvaluator().getOperator() == Operator.EQUAL);
}
}
return false;
}
public ContextEntry[] createContext() {
return new ContextEntry[] { this.constraint.createContextEntry() };
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#updateFromTuple(org.drools.reteoo.ReteTuple)
*/
public void updateFromTuple(final ContextEntry[] context,
final InternalWorkingMemory workingMemory,
final LeftTuple tuple) {
context[0].updateFromTuple( workingMemory,
tuple );
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#updateFromFactHandle(org.drools.common.InternalFactHandle)
*/
public void updateFromFactHandle(final ContextEntry[] context,
final InternalWorkingMemory workingMemory,
final InternalFactHandle handle) {
context[0].updateFromFactHandle( workingMemory,
handle );
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#isAllowedCachedLeft(java.lang.Object)
*/
public boolean isAllowedCachedLeft(final ContextEntry[] context,
final InternalFactHandle handle) {
return this.indexed || this.constraint.isAllowedCachedLeft( context[0],
handle );
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#isAllowedCachedRight(org.drools.reteoo.ReteTuple)
*/
public boolean isAllowedCachedRight(final ContextEntry[] context,
final LeftTuple tuple) {
return this.constraint.isAllowedCachedRight( tuple,
context[0] );
}
public boolean isIndexed() {
return this.indexed;
}
public int getIndexCount() {
return (this.indexed ? 1 : 0);
}
public boolean isEmpty() {
return false;
}
public BetaMemory createBetaMemory(final RuleBaseConfiguration config) {
BetaMemory memory;
if ( this.indexed ) {
final VariableConstraint variableConstraint = (VariableConstraint) this.constraint;
final FieldIndex index = new FieldIndex( variableConstraint.getFieldExtractor(),
variableConstraint.getRequiredDeclarations()[0],
variableConstraint.getEvaluator() );
LeftTupleMemory tupleMemory;
if ( this.conf.isIndexLeftBetaMemory() ) {
tupleMemory = new LeftTupleIndexHashTable( new FieldIndex[]{index} );
} else {
tupleMemory = new LeftTupleList();
}
RightTupleMemory factHandleMemory;
if ( this.conf.isIndexRightBetaMemory() ) {
factHandleMemory = new RightTupleIndexHashTable( new FieldIndex[]{index} );
} else {
factHandleMemory = new RightTupleList();
}
memory = new BetaMemory( config.isSequential() ? null : tupleMemory,
factHandleMemory,
this.createContext() );
} else {
memory = new BetaMemory( config.isSequential() ? null : new LeftTupleList(),
new RightTupleList(),
this.createContext() );
}
return memory;
}
public int hashCode() {
return this.constraint.hashCode();
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#getConstraints()
*/
public LinkedList getConstraints() {
final LinkedList list = new LinkedList();
list.add( new LinkedListEntry( this.constraint ) );
return list;
}
/**
* Determine if another object is equal to this.
*
* @param object
* The object to test.
*
* @return <code>true</code> if <code>object</code> is equal to this,
* otherwise <code>false</code>.
*/
public boolean equals(final Object object) {
if ( this == object ) {
return true;
}
if ( object == null || getClass() != object.getClass() ) {
return false;
}
final SingleBetaConstraints other = (SingleBetaConstraints) object;
return this.constraint == other.constraint || this.constraint.equals( other.constraint );
}
public void resetFactHandle(ContextEntry[] context) {
context[0].resetFactHandle();
}
public void resetTuple(ContextEntry[] context) {
context[0].resetTuple();
}
}