org.drools.core.rule.EntryPointId Maven / Gradle / Ivy
/*
* Copyright 2010 Red Hat, Inc. and/or its affiliates.
*
* 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.core.rule;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.Collections;
import java.util.List;
import java.util.Map;
/**
* This class defines a Rete "Entry Point".
* An entry point is used as a source of facts that
* are scoped to a separate alpha network. The alpha
* network is not shared among separate entry points
* and this allows them to safelly run in parallel
* and concurrent modes.
*/
public class EntryPointId extends ConditionalElement
implements
PatternSource, Externalizable {
public static final EntryPointId DEFAULT = new EntryPointId("DEFAULT");
private static final long serialVersionUID = 510l;
private String entryPointId;
public EntryPointId() {
}
/**
* Constructor.
*
* @param entryPointId the ID for this entry point
*/
public EntryPointId( final String entryPointId ) {
this.entryPointId = entryPointId;
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
entryPointId = (String)in.readObject();
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(entryPointId);
}
/**
* There is not reason to clone this object since it is stateless.
* So a clone() call will return the instance itself.
*/
@Override
public EntryPointId clone() {
return this;
}
/**
* It is not possible to declare any new variables, so always
* return an Empty Map
*/
public Map getInnerDeclarations() {
return Collections.EMPTY_MAP;
}
/**
* It is not possible to nest elements inside an entry point, so
* always return an empty list.
*/
public List getNestedElements() {
return Collections.EMPTY_LIST;
}
/**
* It is not possible to declare and export any variables,
* so always return an empty map
*/
public Map getOuterDeclarations() {
return Collections.EMPTY_MAP;
}
/**
* Not possible to resolve any declaration, so always return null.
*/
public Declaration resolveDeclaration(String identifier) {
return null;
}
/**
* {@inheritDoc}
*/
public String getEntryPointId() {
return this.entryPointId;
}
/* (non-Javadoc)
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
final int PRIME = 31;
int result = 1;
result = PRIME * result + ((entryPointId == null) ? 0 : entryPointId.hashCode());
return result;
}
/* (non-Javadoc)
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if ( this == obj ) return true;
if ( obj == null ) return false;
if ( getClass() != obj.getClass() ) return false;
final EntryPointId other = (EntryPointId) obj;
if ( entryPointId == null ) {
if ( other.entryPointId != null ) return false;
} else if ( !entryPointId.equals( other.entryPointId ) ) return false;
return true;
}
@Override
public String toString() {
return "EntryPoint::"+this.entryPointId;
}
public boolean isPatternScopeDelimiter() {
return true;
}
@Override
public boolean requiresLeftActivation() {
return false;
}
}