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.resource;
019
020 import java.io.IOException;
021 import java.io.InputStream;
022 import java.util.HashMap;
023 import java.util.Locale;
024 import java.util.Map;
025 import java.util.Properties;
026
027 import javax.jdo.PersistenceManagerFactory;
028
029 /**
030 * Helper class to load resources.
031 *
032 * @author Marco หงุ่ยตระกูล-Schulze - marco at nightlabs dot de
033 */
034 public class ResourceHelper
035 {
036 /**
037 * File name of the backend-properties.
038 * @see #getCumulus4jBackendProperties()
039 */
040 protected static final String CUMULUS4J_BACKEND_PROPERTIES = "cumulus4j-backend.properties";
041
042 protected static final String CUMULUS4J_PERSISTENCE_PROPERTIES = "cumulus4j-persistence.properties";
043
044 /**
045 * <p>
046 * Open an {@link InputStream} reading the file {@value #CUMULUS4J_BACKEND_PROPERTIES}.
047 * </p>
048 * <p>
049 * <b>Important:</b> You must close this <code>InputStream</code>!!!
050 * </p>
051 * @return an {@link InputStream} (never <code>null</code>).
052 * @see #getCumulus4jBackendProperties()
053 */
054 protected static InputStream openCumulus4jBackendProperties()
055 {
056 InputStream in = ResourceHelper.class.getResourceAsStream(CUMULUS4J_BACKEND_PROPERTIES);
057 if (in == null)
058 throw new IllegalStateException("Resource does not exist (or cannot be openend): " + CUMULUS4J_BACKEND_PROPERTIES);
059
060 return in;
061 }
062
063 protected static InputStream tryOpenCumulus4jPersistenceProperties()
064 {
065 InputStream in = ResourceHelper.class.getResourceAsStream(CUMULUS4J_PERSISTENCE_PROPERTIES);
066 return in;
067 }
068
069 /**
070 * <p>
071 * Get the backend-properties (from file {@value #CUMULUS4J_BACKEND_PROPERTIES}).
072 * </p>
073 * <p>
074 * The backend-properties are loaded from the file {@value #CUMULUS4J_BACKEND_PROPERTIES}
075 * and used for the configuration of the backend-{@link PersistenceManagerFactory}. This file only
076 * contains connection-independent settings (i.e. things that should never change).
077 * The connection-dependent settings are copied from the frontend-PMF's configuration.
078 * </p>
079 * <p>
080 * Additionally, all properties in the frontend-PMF's configuration starting with
081 * "cumulus4j.datanucleus." or "cumulus4j.javax." are forwarded to the backend-PMF
082 * (without the "cumulus4j."-prefix, of course) <b>overriding</b> the default settings.
083 * </p>
084 * @return a {@link Map} containing all settings from the backend-properties; never <code>null</code>.
085 */
086 public static Map<String, Object> getCumulus4jBackendProperties()
087 {
088 Properties properties = new Properties();
089 try {
090 InputStream in = openCumulus4jBackendProperties();
091 properties.load(in);
092 in.close();
093 } catch (IOException e) { // should never happen as it is a resource => rethrow as RuntimeException
094 throw new RuntimeException(e);
095 }
096
097 return getPropertiesAsMap(properties);
098 }
099
100 public static Map<String, Object> getCumulus4jPersistenceProperties()
101 {
102 Properties properties = new Properties();
103 try {
104 InputStream in = tryOpenCumulus4jPersistenceProperties();
105 if (in != null) {
106 properties.load(in);
107 in.close();
108 }
109 } catch (IOException e) { // should never happen as it is a resource => rethrow as RuntimeException
110 throw new RuntimeException(e);
111 }
112
113 return getPropertiesAsMap(properties);
114 }
115
116 protected static Map<String, Object> getPropertiesAsMap(Properties properties) {
117 Map<String, Object> result = new HashMap<String, Object>(properties.size());
118 for (Map.Entry<?, ?> me : properties.entrySet())
119 result.put(String.valueOf(me.getKey()).toLowerCase(Locale.ENGLISH), String.valueOf(me.getValue()));
120
121 return result;
122 }
123 }