org.drools.core.rule.MutableTypeConstraint 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.concurrent.atomic.AtomicBoolean;
import org.drools.core.spi.AlphaNodeFieldConstraint;
import org.drools.core.spi.BetaNodeFieldConstraint;
import org.drools.core.spi.Constraint;
/**
* A base class for constraints
*/
public abstract class MutableTypeConstraint
implements
AlphaNodeFieldConstraint,
BetaNodeFieldConstraint,
Externalizable {
private Constraint.ConstraintType type = Constraint.ConstraintType.UNKNOWN;
private transient AtomicBoolean inUse = new AtomicBoolean(false);
public void setType( ConstraintType type ) {
this.type = type;
}
public ConstraintType getType() {
return this.type;
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
type = (Constraint.ConstraintType)in.readObject();
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(type);
}
public abstract MutableTypeConstraint clone();
public MutableTypeConstraint cloneIfInUse() {
if (inUse.compareAndSet(false, true)) {
return this;
}
MutableTypeConstraint clone = clone();
clone.inUse.set(true);
return clone;
}
public boolean setInUse() {
return inUse.getAndSet(true);
}
}