001 /*
002 * Cumulus4j - Securing your data in the cloud - http://cumulus4j.org
003 * Copyright (C) 2011 NightLabs Consulting GmbH
004 *
005 * This program is free software: you can redistribute it and/or modify
006 * it under the terms of the GNU Affero General Public License as
007 * published by the Free Software Foundation, either version 3 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful,
011 * but WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
013 * GNU Affero General Public License for more details.
014 *
015 * You should have received a copy of the GNU Affero General Public License
016 * along with this program. If not, see <http://www.gnu.org/licenses/>.
017 */
018 package org.cumulus4j.store;
019
020 import java.util.Properties;
021
022 import javax.jdo.PersistenceManager;
023
024 import org.cumulus4j.store.Cumulus4jConnectionFactory.Cumulus4jManagedConnection;
025 import org.cumulus4j.store.crypto.CryptoContext;
026 import org.cumulus4j.store.model.Sequence2;
027 import org.cumulus4j.store.model.Sequence2DAO;
028 import org.datanucleus.store.valuegenerator.AbstractDatastoreGenerator;
029 import org.datanucleus.store.valuegenerator.ValueGenerationBlock;
030 import org.datanucleus.store.valuegenerator.ValueGenerator;
031
032 /**
033 * {@link ValueGenerator} implementation generating values by incrementing a counter.
034 * @author Marco หงุ่ยตระกูล-Schulze - marco at nightlabs dot de
035 */
036 public class Cumulus4jIncrementGenerator extends AbstractDatastoreGenerator
037 {
038 private String sequenceName;
039
040 /**
041 * Create an instance. This is called by DataNucleus.
042 * @param name symbolic name for the generator.
043 * @param props Properties controlling the behaviour of the generator.
044 */
045 public Cumulus4jIncrementGenerator(String name, Properties props) {
046 super(name, props);
047 allocationSize = 5;
048
049 // TODO Check these names and what we want to use for Cumulus4j (classname or fieldname)
050 if (properties.getProperty("sequence-name") != null) {
051 // Specified sequence-name so use that
052 sequenceName = properties.getProperty("sequence-name");
053 }
054 else if (properties.getProperty("field-name") != null) {
055 // Use field name as the sequence name so we have one sequence per field on the class
056 sequenceName = properties.getProperty("field-name");
057 }
058 else {
059 // Use actual class name as the sequence name so we have one sequence per class
060 sequenceName = properties.getProperty("class-name");
061 }
062 }
063
064 @Override
065 protected ValueGenerationBlock reserveBlock(long size) {
066 if (size > Integer.MAX_VALUE)
067 throw new IllegalStateException("Cannot reserve a block of more than " + Integer.MAX_VALUE + " values!");
068
069 Long[] values = new Long[(int)size];
070 Cumulus4jManagedConnection mconn = (Cumulus4jManagedConnection) connectionProvider.retrieveConnection();
071 try {
072 PersistenceManagerConnection pmConn = (PersistenceManagerConnection)mconn.getConnection();
073 PersistenceManager pm = pmConn.getDataPM();
074 Cumulus4jStoreManager storeManager = (Cumulus4jStoreManager) storeMgr;
075
076 CryptoContext cryptoContext = new CryptoContext(
077 storeManager.getEncryptionCoordinateSetManager(),
078 storeManager.getKeyStoreRefManager(),
079 mconn.getExecutionContext(),
080 pmConn
081 );
082 storeManager.getDatastoreVersionManager().applyOnce(cryptoContext);
083
084 pm.currentTransaction().setSerializeRead(true);
085 try {
086 Sequence2 sequence = new Sequence2DAO(pm, cryptoContext.getKeyStoreRefID()).createSequence2(sequenceName);
087 long nextValue = sequence.getNextValue();
088 for (int idx = 0; idx < values.length; ++idx) {
089 values[idx] = nextValue++;
090 }
091 sequence.setNextValue(nextValue);
092 } finally {
093 pm.currentTransaction().setSerializeRead(false);
094 }
095 } finally {
096 connectionProvider.releaseConnection();
097 }
098 return new ValueGenerationBlock(values);
099 }
100 }