/*
* 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.List;
import org.drools.RuleBaseConfiguration;
import org.drools.core.util.index.LeftTupleList;
import org.drools.core.util.index.RightTupleList;
import org.drools.reteoo.BetaMemory;
import org.drools.reteoo.BetaNode;
import org.drools.reteoo.LeftTuple;
import org.drools.reteoo.builder.BuildContext;
import org.drools.rule.ContextEntry;
import org.drools.spi.BetaNodeFieldConstraint;
public class EmptyBetaConstraints
implements
BetaConstraints {
private static final BetaConstraints INSTANCE = new EmptyBetaConstraints();
private static final ContextEntry[] EMPTY = new ContextEntry[0];
public static BetaConstraints getInstance() {
return EmptyBetaConstraints.INSTANCE;
}
private static final long serialVersionUID = 510l;
public EmptyBetaConstraints() {
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
}
public void writeExternal(ObjectOutput out) throws IOException {
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#updateFromTuple(org.drools.reteoo.ReteTuple)
*/
public void updateFromTuple(final ContextEntry[] context,
final InternalWorkingMemory workingMemory,
final LeftTuple 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) {
}
public void resetTuple(final ContextEntry[] context) {
}
public void resetFactHandle(final ContextEntry[] context) {
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#isAllowedCachedLeft(java.lang.Object)
*/
public boolean isAllowedCachedLeft(final ContextEntry[] context,
final InternalFactHandle handle) {
return true;
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#isAllowedCachedRight(org.drools.reteoo.ReteTuple)
*/
public boolean isAllowedCachedRight(final ContextEntry[] context,
final LeftTuple tuple) {
return true;
}
public boolean isIndexed() {
return false;
}
public int getIndexCount() {
return 0;
}
public boolean isEmpty() {
return true;
}
public BetaMemory createBetaMemory(final RuleBaseConfiguration config,
final short nodeType) {
final BetaMemory memory = new BetaMemory( config.isSequential() ? null : new LeftTupleList(),
new RightTupleList(),
this.createContext(),
nodeType );
return memory;
}
public int hashCode() {
return 1;
}
/* (non-Javadoc)
* @see org.drools.common.BetaNodeConstraints#getConstraints()
*/
public BetaNodeFieldConstraint[] getConstraints() {
return new BetaNodeFieldConstraint[0];
}
/**
* 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;
}
return (object != null && (object instanceof EmptyBetaConstraints));
}
public ContextEntry[] createContext() {
return EMPTY;
}
public BetaConstraints getOriginalConstraint() {
throw new UnsupportedOperationException();
}
public long getListenedPropertyMask(List<String> settableProperties) {
return 0L;
}
public void init(BuildContext context, short betaNodeType) { }
public void initIndexes(int depth, short betaNodeType) { }
public boolean isLeftUpdateOptimizationAllowed() {
return true;
}
}