/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.isis.runtimes.dflt.runtime.persistence.oidgenerator.simple;
import static org.apache.isis.core.commons.ensure.Ensure.ensureThatArg;
import static org.apache.isis.core.commons.matchers.IsisMatchers.greaterThan;
import static org.hamcrest.CoreMatchers.is;
import org.apache.isis.core.commons.debug.DebugBuilder;
import org.apache.isis.core.metamodel.adapter.oid.Oid;
import org.apache.isis.core.metamodel.adapter.oid.stringable.directly.OidStringifierDirect;
import org.apache.isis.runtimes.dflt.runtime.persistence.oidgenerator.OidGeneratorAbstract;
import org.apache.isis.runtimes.dflt.runtime.system.persistence.OidGenerator;
/**
* Generates OIDs based on monotonically.
*
* <p>
* Specifies the {@link OidStringifierDirect} as the {@link #getOidStringifier() OID stringifier} ({@link SerialOid} is
* conformant)).
*/
public class SimpleOidGenerator extends OidGeneratorAbstract {
public static class Memento {
private final long persistentSerialNumber;
private final long transientSerialNumber;
Memento(final long persistentSerialNumber, final long transientSerialNumber) {
this.persistentSerialNumber = persistentSerialNumber;
this.transientSerialNumber = transientSerialNumber;
}
public long getTransientSerialNumber() {
return transientSerialNumber;
}
public long getPersistentSerialNumber() {
return persistentSerialNumber;
}
}
private long persistentSerialNumber;
private long transientSerialNumber;
private long aggregatedId;
// //////////////////////////////////////////////////////////////
// constructor
// //////////////////////////////////////////////////////////////
public SimpleOidGenerator() {
this(1);
}
/**
* Persistent {@link Oid}s count up from the provided seed parameter, while {@link Oid#isTransient()} transient
* {@link Oid}s count down.
*/
public SimpleOidGenerator(final long seed) {
this(seed, Long.MIN_VALUE + seed);
}
public SimpleOidGenerator(final Memento memento) {
this(memento.getPersistentSerialNumber(), memento.getTransientSerialNumber());
}
private SimpleOidGenerator(final long persistentSerialNumber, final long transientSerialNumber) {
super(new OidStringifierDirect(SerialOid.class));
ensureThatArg(persistentSerialNumber, is(greaterThan(0L)));
this.persistentSerialNumber = persistentSerialNumber;
this.transientSerialNumber = transientSerialNumber;
}
// //////////////////////////////////////////////////////////////
// name
// //////////////////////////////////////////////////////////////
public String name() {
return "Simple Serial OID Generator";
}
// //////////////////////////////////////////////////////////////
// main API
// //////////////////////////////////////////////////////////////
@Override
public synchronized SerialOid createTransientOid(final Object object) {
return SerialOid.createTransient(transientSerialNumber--); // counts down
}
@Override
public synchronized void convertTransientToPersistentOid(final Oid oid) {
if (!(oid instanceof SerialOid)) {
throw new IllegalArgumentException("Oid is not a SerialOid");
}
final SerialOid serialOid = (SerialOid) oid;
serialOid.setId(persistentSerialNumber++); // counts up
serialOid.makePersistent();
}
@Override
public String createAggregateId(final Object pojo) {
return Long.toHexString(aggregatedId++);
}
// //////////////////////////////////////////////////////////////
// Memento (not API)
// //////////////////////////////////////////////////////////////
public Memento getMemento() {
return new Memento(this.persistentSerialNumber, this.transientSerialNumber);
}
/**
* Reset to a {@link Memento} previously obtained via {@link #getMemento()}.
*
* <p>
* Used in particular by the <tt>InMemoryObjectStore</tt> to reset (a new {@link OidGenerator} is created each
* time).
*/
public void resetTo(final Memento memento) {
this.persistentSerialNumber = memento.getPersistentSerialNumber();
this.transientSerialNumber = memento.getTransientSerialNumber();
}
// //////////////////////////////////////////////////////////////
// debug
// //////////////////////////////////////////////////////////////
@Override
public void debugData(final DebugBuilder debug) {
debug.appendln("Persistent", persistentSerialNumber);
debug.appendln("Transient", transientSerialNumber);
}
@Override
public String debugTitle() {
return name();
}
}