| /* |
| * Copyright 2012, Paul Merlin. |
| * |
| * 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.apache.zest.entitystore.leveldb; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.io.Reader; |
| import java.io.StringReader; |
| import java.io.StringWriter; |
| import java.io.Writer; |
| import java.nio.charset.Charset; |
| import org.iq80.leveldb.CompressionType; |
| import org.iq80.leveldb.DB; |
| import org.iq80.leveldb.DBFactory; |
| import org.iq80.leveldb.DBIterator; |
| import org.iq80.leveldb.Options; |
| import org.iq80.leveldb.WriteBatch; |
| import org.apache.zest.api.configuration.Configuration; |
| import org.apache.zest.api.entity.EntityDescriptor; |
| import org.apache.zest.api.entity.EntityReference; |
| import org.apache.zest.api.injection.scope.Service; |
| import org.apache.zest.api.injection.scope.This; |
| import org.apache.zest.api.injection.scope.Uses; |
| import org.apache.zest.api.service.ServiceActivation; |
| import org.apache.zest.api.service.ServiceDescriptor; |
| import org.apache.zest.io.Input; |
| import org.apache.zest.io.Output; |
| import org.apache.zest.io.Receiver; |
| import org.apache.zest.io.Sender; |
| import org.apache.zest.library.fileconfig.FileConfiguration; |
| import org.apache.zest.spi.entitystore.EntityNotFoundException; |
| import org.apache.zest.spi.entitystore.EntityStoreException; |
| import org.apache.zest.spi.entitystore.helpers.MapEntityStore; |
| |
| /** |
| * LevelDB implementation of MapEntityStore. |
| */ |
| public class LevelDBEntityStoreMixin |
| implements ServiceActivation, MapEntityStore |
| { |
| |
| @Service |
| private FileConfiguration fileConfig; |
| @This |
| private Configuration<LevelDBEntityStoreConfiguration> configuration; |
| @Uses |
| private ServiceDescriptor descriptor; |
| private Charset charset; |
| private DB db; |
| |
| @Override |
| public void activateService() |
| throws Exception |
| { |
| charset = Charset.forName( "UTF-8" ); |
| configuration.refresh(); |
| LevelDBEntityStoreConfiguration config = configuration.get(); |
| |
| // Choose flavour |
| String flavour = config.flavour().get(); |
| DBFactory factory; |
| if( "jni".equalsIgnoreCase( flavour ) ) |
| { |
| factory = newJniDBFactory(); |
| } |
| else if( "java".equalsIgnoreCase( flavour ) ) |
| { |
| factory = newJavaDBFactory(); |
| } |
| else |
| { |
| factory = newDBFactory(); |
| } |
| |
| // Apply configuration |
| Options options = new Options(); |
| options.createIfMissing( true ); |
| if( config.blockRestartInterval().get() != null ) |
| { |
| options.blockRestartInterval( config.blockRestartInterval().get() ); |
| } |
| if( config.blockSize().get() != null ) |
| { |
| options.blockSize( config.blockSize().get() ); |
| } |
| if( config.cacheSize().get() != null ) |
| { |
| options.cacheSize( config.cacheSize().get() ); |
| } |
| if( config.compression().get() != null ) |
| { |
| options.compressionType( config.compression().get() |
| ? CompressionType.SNAPPY |
| : CompressionType.NONE ); |
| } |
| if( config.maxOpenFiles().get() != null ) |
| { |
| options.maxOpenFiles( config.maxOpenFiles().get() ); |
| } |
| if( config.paranoidChecks().get() != null ) |
| { |
| options.paranoidChecks( config.paranoidChecks().get() ); |
| } |
| if( config.verifyChecksums().get() != null ) |
| { |
| options.verifyChecksums( config.verifyChecksums().get() ); |
| } |
| if( config.writeBufferSize().get() != null ) |
| { |
| options.writeBufferSize( config.writeBufferSize().get() ); |
| } |
| |
| // Open/Create the database |
| File dbFile = new File( fileConfig.dataDirectory(), descriptor.identity() ); |
| db = factory.open( dbFile, options ); |
| } |
| |
| /** |
| * Tries in order: JNI and then pure Java LevelDB implementations. |
| */ |
| private DBFactory newDBFactory() |
| { |
| try |
| { |
| return newJniDBFactory(); |
| } |
| catch( Exception ex ) |
| { |
| try |
| { |
| return newJavaDBFactory(); |
| } |
| catch( Exception ex2 ) |
| { |
| throw new RuntimeException( "Unable to create a LevelDB DBFactory instance. " |
| + "Tried JNI and pure Java. " |
| + "The stacktrace is the pure Java attempt.", ex2 ); |
| } |
| } |
| } |
| |
| private DBFactory newJniDBFactory() |
| throws Exception |
| { |
| return (DBFactory) Class.forName( "org.fusesource.leveldbjni.JniDBFactory" ).newInstance(); |
| } |
| |
| private DBFactory newJavaDBFactory() |
| throws Exception |
| { |
| return (DBFactory) Class.forName( "org.iq80.leveldb.impl.Iq80DBFactory" ).newInstance(); |
| } |
| |
| @Override |
| public void passivateService() |
| throws Exception |
| { |
| try |
| { |
| db.close(); |
| } |
| finally |
| { |
| db = null; |
| charset = null; |
| } |
| } |
| |
| @Override |
| public Reader get( EntityReference entityReference ) |
| throws EntityStoreException |
| { |
| byte[] state = db.get( entityReference.identity().getBytes( charset ) ); |
| if( state == null ) |
| { |
| throw new EntityNotFoundException( entityReference ); |
| } |
| String jsonState = new String( state, charset ); |
| return new StringReader( jsonState ); |
| } |
| |
| @Override |
| public Input<Reader, IOException> entityStates() |
| { |
| return new Input<Reader, IOException>() |
| { |
| |
| @Override |
| public <ReceiverThrowableType extends Throwable> void transferTo( Output<? super Reader, ReceiverThrowableType> output ) |
| throws IOException, ReceiverThrowableType |
| { |
| output.receiveFrom( new Sender<Reader, IOException>() |
| { |
| |
| @Override |
| public <ReceiverThrowableType extends Throwable> void sendTo( Receiver<? super Reader, ReceiverThrowableType> receiver ) |
| throws ReceiverThrowableType, IOException |
| { |
| DBIterator iterator = db.iterator(); |
| try |
| { |
| for( iterator.seekToFirst(); iterator.hasNext(); iterator.next() ) |
| { |
| byte[] state = iterator.peekNext().getValue(); |
| String jsonState = new String( state, charset ); |
| receiver.receive( new StringReader( jsonState ) ); |
| } |
| } |
| finally |
| { |
| iterator.close(); |
| } |
| } |
| |
| } ); |
| } |
| |
| }; |
| } |
| |
| @Override |
| public void applyChanges( MapChanges changes ) |
| throws IOException |
| { |
| final WriteBatch writeBatch = db.createWriteBatch(); |
| try |
| { |
| changes.visitMap( new MapChanger() |
| { |
| |
| @Override |
| public Writer newEntity( final EntityReference ref, EntityDescriptor entityDescriptor ) |
| throws IOException |
| { |
| return new StringWriter( 1000 ) |
| { |
| |
| @Override |
| public void close() |
| throws IOException |
| { |
| super.close(); |
| String jsonState = toString(); |
| writeBatch.put( ref.identity().getBytes( charset ), jsonState.getBytes( charset ) ); |
| } |
| |
| }; |
| } |
| |
| @Override |
| public Writer updateEntity( final EntityReference ref, EntityDescriptor entityDescriptor ) |
| throws IOException |
| { |
| return new StringWriter( 1000 ) |
| { |
| |
| @Override |
| public void close() |
| throws IOException |
| { |
| super.close(); |
| String jsonState = toString(); |
| writeBatch.put( ref.identity().getBytes( charset ), jsonState.getBytes( charset ) ); |
| } |
| |
| }; |
| } |
| |
| @Override |
| public void removeEntity( EntityReference ref, EntityDescriptor entityDescriptor ) |
| throws EntityNotFoundException |
| { |
| writeBatch.delete( ref.identity().getBytes( charset ) ); |
| } |
| |
| } ); |
| db.write( writeBatch ); |
| } |
| finally |
| { |
| writeBatch.close(); |
| } |
| } |
| |
| } |