/**
* 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 java.util.ArrayList;
import java.util.List;
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.VariableConstraint;
import org.drools.spi.BetaNodeFieldConstraint;
import org.drools.spi.Constraint;
public class DefaultBetaConstraints
implements
BetaConstraints {
/**
*
*/
private static final long serialVersionUID = 510l;
private LinkedList constraints;
private int indexed;
public DefaultBetaConstraints() {
}
public DefaultBetaConstraints(final BetaNodeFieldConstraint[] constraints,
final RuleBaseConfiguration conf) {
this( constraints,
conf,
false );
}
public DefaultBetaConstraints(final BetaNodeFieldConstraint[] constraints,
final RuleBaseConfiguration conf,
final boolean disableIndexing) {
this.indexed = -1;
this.constraints = new LinkedList();
final int depth = conf.getCompositeKeyDepth();
// First create a LinkedList of constraints, with the indexed constraints first.
for ( int i = 0, length = constraints.length; i < length; i++ ) {
// Determine if this constraint is indexable
if ( (!disableIndexing) && conf.isIndexLeftBetaMemory() && conf.isIndexRightBetaMemory() && isIndexable( constraints[i] ) && (this.indexed < depth - 1) ) {
if ( depth >= 1 && this.indexed == -1 ) {
// first index, so just add to the front
this.constraints.insertAfter( null,
new LinkedListEntry( constraints[i] ) );
this.indexed++;
} else {
// insert this index after the previous index
this.constraints.insertAfter( findNode( this.indexed++ ),
new LinkedListEntry( constraints[i] ) );
}
} else {
// not indexed, so just add to the end
this.constraints.add( new LinkedListEntry( constraints[i] ) );
}
}
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
constraints = (LinkedList)in.readObject();
indexed = in.readInt();
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(constraints);
out.writeInt(indexed);
}
public ContextEntry[] createContext() {
// Now create the ContextEntries in the same order the constraints
ContextEntry[] contexts = new ContextEntry[this.constraints.size()];
int i = 0;
for ( LinkedListEntry entry = (LinkedListEntry) this.constraints.getFirst(); entry != null; entry = (LinkedListEntry) entry.getNext() ) {
final BetaNodeFieldConstraint constraint = (BetaNodeFieldConstraint) entry.getObject();
contexts[i++] = constraint.createContextEntry();
}
return contexts;
}
private LinkedListEntry findNode(final int pos) {
LinkedListEntry current = (LinkedListEntry) this.constraints.getFirst();
for ( int i = 0; i < pos; i++ ) {
current = (LinkedListEntry) current.getNext();
}
return current;
}
private boolean isIndexable(final BetaNodeFieldConstraint constraint) {
if ( constraint instanceof VariableConstraint ) {
final VariableConstraint variableConstraint = (VariableConstraint) constraint;
return (variableConstraint.getEvaluator().getOperator() == Operator.EQUAL);
} else {
return false;
}
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#updateFromTuple(org.drools.reteoo.ReteTuple)
*/
public void updateFromTuple(final ContextEntry[] context,
final InternalWorkingMemory workingMemory,
final LeftTuple tuple) {
for ( int i = 0; i < context.length; i++ ) {
context[i].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) {
for ( int i = 0; i < context.length; i++ ) {
context[i].updateFromFactHandle( workingMemory,
handle );
}
}
public void resetTuple(final ContextEntry[] context) {
for ( int i = 0; i < context.length; i++ ) {
context[i].resetTuple();
}
}
public void resetFactHandle(final ContextEntry[] context) {
for ( int i = 0; i < context.length; i++ ) {
context[i].resetFactHandle();
}
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#isAllowedCachedLeft(java.lang.Object)
*/
public boolean isAllowedCachedLeft(final ContextEntry[] context,
final InternalFactHandle handle) {
// skip the indexed constraints
LinkedListEntry entry = (LinkedListEntry) findNode( this.indexed+1 );
int i = 1;
while ( entry != null ) {
if ( !((BetaNodeFieldConstraint) entry.getObject()).isAllowedCachedLeft( context[this.indexed + i],
handle ) ) {
return false;
}
entry = (LinkedListEntry) entry.getNext();
i++;
}
return true;
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#isAllowedCachedRight(org.drools.reteoo.ReteTuple)
*/
public boolean isAllowedCachedRight(final ContextEntry[] context,
final LeftTuple tuple) {
// skip the indexed constraints
LinkedListEntry entry = (LinkedListEntry) findNode( this.indexed+1 );
int i = 1;
while ( entry != null ) {
if ( !((BetaNodeFieldConstraint) entry.getObject()).isAllowedCachedRight( tuple,
context[this.indexed + i] ) ) {
return false;
}
entry = (LinkedListEntry) entry.getNext();
i++;
}
return true;
}
public boolean isIndexed() {
// false if -1
return this.indexed >= 0;
}
public int getIndexCount() {
return this.indexed + 1;
}
public boolean isEmpty() {
return false;
}
public BetaMemory createBetaMemory(RuleBaseConfiguration config) {
BetaMemory memory;
if ( this.indexed >= 0 ) {
LinkedListEntry entry = (LinkedListEntry) this.constraints.getFirst();
final List list = new ArrayList();
for ( int pos = 0; pos <= this.indexed; pos++ ) {
final Constraint constraint = (Constraint) entry.getObject();
final VariableConstraint variableConstraint = (VariableConstraint) constraint;
final FieldIndex index = new FieldIndex( variableConstraint.getFieldExtractor(),
variableConstraint.getRequiredDeclarations()[0],
variableConstraint.getEvaluator() );
list.add( index );
entry = (LinkedListEntry) entry.getNext();
}
final FieldIndex[] indexes = (FieldIndex[]) list.toArray( new FieldIndex[list.size()] );
LeftTupleMemory tupleMemory;
if ( config.isIndexLeftBetaMemory() ) {
tupleMemory = new LeftTupleIndexHashTable( indexes );
} else {
tupleMemory = new LeftTupleList();
}
RightTupleMemory factHandleMemory;
if ( config.isIndexRightBetaMemory() ) {
factHandleMemory = new RightTupleIndexHashTable( indexes );
} 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.constraints.hashCode();
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#getConstraints()
*/
public LinkedList getConstraints() {
return this.constraints;
}
/**
* 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 || !(object instanceof DefaultBetaConstraints) ) {
return false;
}
final DefaultBetaConstraints other = (DefaultBetaConstraints) object;
if ( this.constraints == other.constraints ) {
return true;
}
if ( this.constraints.size() != other.constraints.size() ) {
return false;
}
return this.constraints.equals( other.constraints );
}
}