/*
* Copyright (c) 2008, Rickard Öberg. All Rights Reserved.
*
* 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.qi4j.entitystore.prefs;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.prefs.BackingStoreException;
import java.util.prefs.Preferences;
import org.qi4j.api.association.AssociationDescriptor;
import org.qi4j.api.cache.CacheOptions;
import org.qi4j.api.common.QualifiedName;
import org.qi4j.api.entity.EntityDescriptor;
import org.qi4j.api.entity.EntityReference;
import org.qi4j.api.injection.scope.Service;
import org.qi4j.api.injection.scope.Structure;
import org.qi4j.api.injection.scope.This;
import org.qi4j.api.injection.scope.Uses;
import org.qi4j.api.property.PropertyDescriptor;
import org.qi4j.api.service.ServiceActivation;
import org.qi4j.api.service.ServiceDescriptor;
import org.qi4j.api.service.qualifier.Tagged;
import org.qi4j.api.structure.Application;
import org.qi4j.api.structure.Module;
import org.qi4j.api.type.CollectionType;
import org.qi4j.api.type.EnumType;
import org.qi4j.api.type.MapType;
import org.qi4j.api.type.ValueCompositeType;
import org.qi4j.api.type.ValueType;
import org.qi4j.api.unitofwork.EntityTypeNotFoundException;
import org.qi4j.api.unitofwork.NoSuchEntityException;
import org.qi4j.api.usecase.Usecase;
import org.qi4j.api.usecase.UsecaseBuilder;
import org.qi4j.api.value.ValueSerialization;
import org.qi4j.api.value.ValueSerializationException;
import org.qi4j.io.Input;
import org.qi4j.io.Output;
import org.qi4j.io.Receiver;
import org.qi4j.io.Sender;
import org.qi4j.spi.entity.EntityState;
import org.qi4j.spi.entity.EntityStatus;
import org.qi4j.spi.entitystore.DefaultEntityStoreUnitOfWork;
import org.qi4j.spi.entitystore.EntityStore;
import org.qi4j.spi.entitystore.EntityStoreException;
import org.qi4j.spi.entitystore.EntityStoreSPI;
import org.qi4j.spi.entitystore.EntityStoreUnitOfWork;
import org.qi4j.spi.entitystore.StateCommitter;
import org.qi4j.spi.entitystore.helpers.DefaultEntityState;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import static org.qi4j.functional.Iterables.first;
/**
* Implementation of EntityStore that is backed by the Preferences API.
*
* <p>@see Preferences</p>
* <p>ManyAssociation is stored as string, one identity string per line</p>
* <p>Nested ValuesComposites, Collections and Maps are stored using available ValueSerialization service.</p>
*/
public class PreferencesEntityStoreMixin
implements ServiceActivation, EntityStore, EntityStoreSPI
{
@This
private EntityStoreSPI entityStoreSpi;
@Uses
private ServiceDescriptor descriptor;
@Structure
private Application application;
@Service
@Tagged( ValueSerialization.Formats.JSON )
private ValueSerialization valueSerialization;
private Preferences root;
protected String uuid;
private int count;
public Logger logger;
public ScheduledThreadPoolExecutor reloadExecutor;
@Override
public void activateService()
throws Exception
{
root = getApplicationRoot();
logger = LoggerFactory.getLogger( PreferencesEntityStoreService.class.getName() );
logger.info( "Preferences store:" + root.absolutePath() );
uuid = UUID.randomUUID().toString() + "-";
// Reload underlying store every 60 seconds
reloadExecutor = new ScheduledThreadPoolExecutor( 1 );
reloadExecutor.setExecuteExistingDelayedTasksAfterShutdownPolicy( false );
reloadExecutor.scheduleAtFixedRate( new Runnable()
{
@Override
public void run()
{
try
{
synchronized( root )
{
root.sync();
}
}
catch( BackingStoreException e )
{
logger.warn( "Could not reload preferences", e );
}
}
}, 0, 60, TimeUnit.SECONDS );
}
private Preferences getApplicationRoot()
{
PreferencesEntityStoreInfo storeInfo = descriptor.metaInfo( PreferencesEntityStoreInfo.class );
Preferences preferences;
if( storeInfo == null )
{
// Default to use system root + application name
preferences = Preferences.systemRoot();
String name = application.name();
preferences = preferences.node( name );
}
else
{
preferences = storeInfo.rootNode();
}
return preferences;
}
@Override
public void passivateService()
throws Exception
{
reloadExecutor.shutdown();
reloadExecutor.awaitTermination( 10, TimeUnit.SECONDS );
}
@Override
public EntityStoreUnitOfWork newUnitOfWork( Usecase usecase, Module module, long currentTime )
{
return new DefaultEntityStoreUnitOfWork( entityStoreSpi, newUnitOfWorkId(), module, usecase, currentTime );
}
@Override
public Input<EntityState, EntityStoreException> entityStates( final Module module )
{
return new Input<EntityState, EntityStoreException>()
{
@Override
public <ReceiverThrowableType extends Throwable> void transferTo( Output<? super EntityState, ReceiverThrowableType> output )
throws EntityStoreException, ReceiverThrowableType
{
output.receiveFrom( new Sender<EntityState, EntityStoreException>()
{
@Override
public <ReceiverThrowableType extends Throwable> void sendTo( Receiver<? super EntityState, ReceiverThrowableType> receiver )
throws ReceiverThrowableType, EntityStoreException
{
UsecaseBuilder builder = UsecaseBuilder.buildUsecase( "qi4j.entitystore.preferences.visit" );
Usecase visitUsecase = builder.withMetaInfo( CacheOptions.NEVER ).newUsecase();
final DefaultEntityStoreUnitOfWork uow = new DefaultEntityStoreUnitOfWork( entityStoreSpi, newUnitOfWorkId(),
module, visitUsecase, System
.currentTimeMillis() );
try
{
String[] identities = root.childrenNames();
for( String identity : identities )
{
EntityState entityState = uow.entityStateOf( EntityReference.parseEntityReference( identity ) );
receiver.receive( entityState );
}
}
catch( BackingStoreException e )
{
throw new EntityStoreException( e );
}
}
} );
}
};
}
@Override
public EntityState newEntityState( EntityStoreUnitOfWork unitOfWork,
EntityReference identity,
EntityDescriptor entityDescriptor
)
{
return new DefaultEntityState( (DefaultEntityStoreUnitOfWork) unitOfWork, identity, entityDescriptor );
}
@Override
public EntityState entityStateOf( EntityStoreUnitOfWork unitOfWork, EntityReference identity )
{
try
{
DefaultEntityStoreUnitOfWork desuw = (DefaultEntityStoreUnitOfWork) unitOfWork;
Module module = desuw.module();
if( !root.nodeExists( identity.identity() ) )
{
throw new NoSuchEntityException( identity );
}
Preferences entityPrefs = root.node( identity.identity() );
String type = entityPrefs.get( "type", null );
EntityStatus status = EntityStatus.LOADED;
EntityDescriptor entityDescriptor = module.entityDescriptor( type );
if( entityDescriptor == null )
{
throw new EntityTypeNotFoundException( type );
}
Map<QualifiedName, Object> properties = new HashMap<QualifiedName, Object>();
Preferences propsPrefs = null;
for( PropertyDescriptor persistentPropertyDescriptor : entityDescriptor.state().properties() )
{
if( persistentPropertyDescriptor.qualifiedName().name().equals( "identity" ) )
{
// Fake identity property
properties.put( persistentPropertyDescriptor.qualifiedName(), identity.identity() );
continue;
}
if( propsPrefs == null )
{
propsPrefs = entityPrefs.node( "properties" );
}
ValueType propertyType = persistentPropertyDescriptor.valueType();
Class<?> mainType = propertyType.mainType();
if( Number.class.isAssignableFrom( mainType ) )
{
if( mainType.equals( Long.class ) )
{
properties.put( persistentPropertyDescriptor.qualifiedName(),
this.getNumber( propsPrefs, persistentPropertyDescriptor, new NumberParser<Long>()
{
@Override
public Long parse( String str )
{
return Long.parseLong( str );
}
} ) );
}
else if( mainType.equals( Integer.class ) )
{
properties.put( persistentPropertyDescriptor.qualifiedName(),
this.getNumber( propsPrefs, persistentPropertyDescriptor, new NumberParser<Integer>()
{
@Override
public Integer parse( String str )
{
return Integer.parseInt( str );
}
} ) );
}
else if( mainType.equals( Double.class ) )
{
properties.put( persistentPropertyDescriptor.qualifiedName(),
this.getNumber( propsPrefs, persistentPropertyDescriptor, new NumberParser<Double>()
{
@Override
public Double parse( String str )
{
return Double.parseDouble( str );
}
} ) );
}
else if( mainType.equals( Float.class ) )
{
properties.put( persistentPropertyDescriptor.qualifiedName(),
this.getNumber( propsPrefs, persistentPropertyDescriptor, new NumberParser<Float>()
{
@Override
public Float parse( String str )
{
return Float.parseFloat( str );
}
} ) );
}
else
{
// Load as string even though it's a number
String json = propsPrefs.get( persistentPropertyDescriptor.qualifiedName().name(), null );
Object value;
if( json == null )
{
value = null;
}
else
{
value = valueSerialization.deserialize( persistentPropertyDescriptor.valueType(), json );
}
properties.put( persistentPropertyDescriptor.qualifiedName(), value );
}
}
else if( mainType.equals( Boolean.class ) )
{
Boolean initialValue = (Boolean) persistentPropertyDescriptor.initialValue( module );
properties.put( persistentPropertyDescriptor.qualifiedName(),
propsPrefs.getBoolean( persistentPropertyDescriptor.qualifiedName().name(),
initialValue == null ? false : initialValue ) );
}
else if( propertyType instanceof ValueCompositeType ||
propertyType instanceof MapType ||
propertyType instanceof CollectionType ||
propertyType instanceof EnumType )
{
String json = propsPrefs.get( persistentPropertyDescriptor.qualifiedName().name(), null );
Object value;
if( json == null )
{
value = null;
}
else
{
value = valueSerialization.deserialize( persistentPropertyDescriptor.valueType(), json );
}
properties.put( persistentPropertyDescriptor.qualifiedName(), value );
}
else
{
String json = propsPrefs.get( persistentPropertyDescriptor.qualifiedName().name(), null );
if( json == null )
{
if( persistentPropertyDescriptor.initialValue( module ) != null )
{
properties.put( persistentPropertyDescriptor.qualifiedName(), persistentPropertyDescriptor.initialValue( module ) );
}
else
{
properties.put( persistentPropertyDescriptor.qualifiedName(), null );
}
}
else
{
Object value = valueSerialization.deserialize( propertyType, json );
properties.put( persistentPropertyDescriptor.qualifiedName(), value );
}
}
}
// Associations
Map<QualifiedName, EntityReference> associations = new HashMap<QualifiedName, EntityReference>();
Preferences assocs = null;
for( AssociationDescriptor associationType : entityDescriptor.state().associations() )
{
if( assocs == null )
{
assocs = entityPrefs.node( "associations" );
}
String associatedEntity = assocs.get( associationType.qualifiedName().name(), null );
EntityReference value = associatedEntity == null ? null : EntityReference.parseEntityReference(
associatedEntity );
associations.put( associationType.qualifiedName(), value );
}
// ManyAssociations
Map<QualifiedName, List<EntityReference>> manyAssociations = new HashMap<QualifiedName, List<EntityReference>>();
Preferences manyAssocs = null;
for( AssociationDescriptor manyAssociationType : entityDescriptor.state().manyAssociations() )
{
if( manyAssocs == null )
{
manyAssocs = entityPrefs.node( "manyassociations" );
}
List<EntityReference> references = new ArrayList<EntityReference>();
String entityReferences = manyAssocs.get( manyAssociationType.qualifiedName().name(), null );
if( entityReferences == null )
{
// ManyAssociation not found, default to empty one
manyAssociations.put( manyAssociationType.qualifiedName(), references );
}
else
{
String[] refs = entityReferences.split( "\n" );
for( String ref : refs )
{
EntityReference value = ref == null ? null : EntityReference.parseEntityReference( ref );
references.add( value );
}
manyAssociations.put( manyAssociationType.qualifiedName(), references );
}
}
return new DefaultEntityState( desuw,
entityPrefs.get( "version", "" ),
entityPrefs.getLong( "modified", unitOfWork.currentTime() ),
identity,
status,
entityDescriptor,
properties,
associations,
manyAssociations
);
}
catch( ValueSerializationException e )
{
throw new EntityStoreException( e );
}
catch( BackingStoreException e )
{
throw new EntityStoreException( e );
}
}
@Override
public StateCommitter applyChanges( final EntityStoreUnitOfWork unitofwork, final Iterable<EntityState> state )
{
return new StateCommitter()
{
@Override
public void commit()
{
try
{
synchronized( root )
{
for( EntityState entityState : state )
{
DefaultEntityState state = (DefaultEntityState) entityState;
if( state.status().equals( EntityStatus.NEW ) )
{
Preferences entityPrefs = root.node( state.identity().identity() );
writeEntityState( state, entityPrefs, unitofwork.identity(), unitofwork.currentTime() );
}
else if( state.status().equals( EntityStatus.UPDATED ) )
{
Preferences entityPrefs = root.node( state.identity().identity() );
writeEntityState( state, entityPrefs, unitofwork.identity(), unitofwork.currentTime() );
}
else if( state.status().equals( EntityStatus.REMOVED ) )
{
root.node( state.identity().identity() ).removeNode();
}
}
root.flush();
}
}
catch( BackingStoreException e )
{
throw new EntityStoreException( e );
}
}
@Override
public void cancel()
{
}
};
}
protected void writeEntityState( DefaultEntityState state,
Preferences entityPrefs,
String identity,
long lastModified
)
throws EntityStoreException
{
try
{
// Store into Preferences API
entityPrefs.put( "type", first( state.entityDescriptor().types() ).getName() );
entityPrefs.put( "version", identity );
entityPrefs.putLong( "modified", lastModified );
// Properties
Preferences propsPrefs = entityPrefs.node( "properties" );
for( PropertyDescriptor persistentProperty : state.entityDescriptor().state().properties() )
{
if( persistentProperty.qualifiedName().name().equals( "identity" ) )
{
continue; // Skip Identity.identity()
}
Object value = state.properties().get( persistentProperty.qualifiedName() );
if( value == null )
{
propsPrefs.remove( persistentProperty.qualifiedName().name() );
}
else
{
ValueType valueType = persistentProperty.valueType();
Class<?> mainType = valueType.mainType();
if( Number.class.isAssignableFrom( mainType ) )
{
if( mainType.equals( Long.class ) )
{
propsPrefs.putLong( persistentProperty.qualifiedName().name(), (Long) value );
}
else if( mainType.equals( Integer.class ) )
{
propsPrefs.putInt( persistentProperty.qualifiedName().name(), (Integer) value );
}
else if( mainType.equals( Double.class ) )
{
propsPrefs.putDouble( persistentProperty.qualifiedName().name(), (Double) value );
}
else if( mainType.equals( Float.class ) )
{
propsPrefs.putFloat( persistentProperty.qualifiedName().name(), (Float) value );
}
else
{
// Store as string even though it's a number
String jsonString = valueSerialization.serialize( value );
propsPrefs.put( persistentProperty.qualifiedName().name(), jsonString );
}
}
else if( mainType.equals( Boolean.class ) )
{
propsPrefs.putBoolean( persistentProperty.qualifiedName().name(), (Boolean) value );
}
else if( valueType instanceof ValueCompositeType ||
valueType instanceof MapType ||
valueType instanceof CollectionType ||
valueType instanceof EnumType )
{
String jsonString = valueSerialization.serialize( value );
propsPrefs.put( persistentProperty.qualifiedName().name(), jsonString );
}
else
{
String jsonString = valueSerialization.serialize( value );
propsPrefs.put( persistentProperty.qualifiedName().name(), jsonString );
}
}
}
// Associations
if( !state.associations().isEmpty() )
{
Preferences assocsPrefs = entityPrefs.node( "associations" );
for( Map.Entry<QualifiedName, EntityReference> association : state.associations().entrySet() )
{
if( association.getValue() == null )
{
assocsPrefs.remove( association.getKey().name() );
}
else
{
assocsPrefs.put( association.getKey().name(), association.getValue().identity() );
}
}
}
// ManyAssociations
if( !state.manyAssociations().isEmpty() )
{
Preferences manyAssocsPrefs = entityPrefs.node( "manyassociations" );
for( Map.Entry<QualifiedName, List<EntityReference>> manyAssociations : state.manyAssociations()
.entrySet() )
{
StringBuilder manyAssocs = new StringBuilder();
for( EntityReference entityReference : manyAssociations.getValue() )
{
if( manyAssocs.length() > 0 )
{
manyAssocs.append( "\n" );
}
manyAssocs.append( entityReference.identity() );
}
if( manyAssocs.length() > 0 )
{
manyAssocsPrefs.put( manyAssociations.getKey().name(), manyAssocs.toString() );
}
}
}
}
catch( ValueSerializationException e )
{
throw new EntityStoreException( "Could not store EntityState", e );
}
}
protected String newUnitOfWorkId()
{
return uuid + Integer.toHexString( count++ );
}
private interface NumberParser<T>
{
T parse( String str );
}
private <T> T getNumber( Preferences prefs, PropertyDescriptor pDesc, NumberParser<T> parser )
{
Object initialValue = pDesc.initialValue( null );
String str = prefs.get( pDesc.qualifiedName().name(), initialValue == null ? null : initialValue.toString() );
T result = null;
if( str != null )
{
result = parser.parse( str );
}
return result;
}
}