Java tutorial
/* * #! * Ontopia Engine * #- * Copyright (C) 2001 - 2013 The Ontopia Project * #- * 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 net.ontopia.topicmaps.impl.rdbms; import java.util.Map; import net.ontopia.infoset.core.LocatorIF; import net.ontopia.persistence.proxy.StorageIF; import net.ontopia.topicmaps.core.StoreDeletedException; import net.ontopia.topicmaps.core.TopicMapStoreFactoryIF; import net.ontopia.topicmaps.core.TopicMapStoreIF; import net.ontopia.topicmaps.entry.AbstractTopicMapReference; import net.ontopia.topicmaps.impl.utils.AbstractTopicMapStore; import net.ontopia.topicmaps.impl.utils.StorePoolableObjectFactory; import net.ontopia.utils.OntopiaRuntimeException; import net.ontopia.utils.PropertyUtils; import org.apache.commons.pool.impl.GenericObjectPool; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * INTERNAL: RDBMS database topic map reference. */ public class RDBMSTopicMapReference extends AbstractTopicMapReference { public static final String EXHAUSED_BLOCK = "block"; public static final String EXHAUSED_GROW = "grow"; public static final String EXHAUSED_FAIL = "fail"; // Define a logging category. static Logger log = LoggerFactory.getLogger(RDBMSTopicMapReference.class.getName()); protected StorageIF storage; protected long topicmap_id; protected LocatorIF base_address; // store pool protected StorePoolableObjectFactory ofactory; protected GenericObjectPool pool; protected RDBMSTopicMapStore rostore; public RDBMSTopicMapReference(String _id, String _title, StorageIF _storage, long _topicmap_id, LocatorIF _base_address) { super(_id, _title); this.storage = _storage; this.topicmap_id = _topicmap_id; this.base_address = _base_address; } protected RDBMSTopicMapStore _createStore(boolean readonly) { RDBMSTopicMapStore store = new RDBMSTopicMapStore(storage, topicmap_id); store.setReadOnly(readonly); store.setReference(RDBMSTopicMapReference.this); if (base_address != null) store.setBaseAddressOverride(base_address); return store; } protected void init() { // store factory TopicMapStoreFactoryIF sfactory = new TopicMapStoreFactoryIF() { public TopicMapStoreIF createStore() { return _createStore(false); } }; // initialize pool this.ofactory = new StorePoolableObjectFactory(sfactory); this.pool = new GenericObjectPool(ofactory); this.pool.setTestOnBorrow(true); Map properties = storage.getProperties(); if (properties != null) { // Set minimum pool size (default: 0) String _minsize = PropertyUtils.getProperty(properties, "net.ontopia.topicmaps.impl.rdbms.StorePool.MinimumSize", false); int minsize = (_minsize == null ? 0 : Integer.parseInt(_minsize)); log.debug("Setting StorePool.MinimumSize '" + minsize + "'"); pool.setMinIdle(minsize); // 0 = no limit // Set maximum pool size (default: Integer.MAX_VALUE) String _maxsize = PropertyUtils.getProperty(properties, "net.ontopia.topicmaps.impl.rdbms.StorePool.MaximumSize", false); int maxsize = (_maxsize == null ? 8 : Integer.parseInt(_maxsize)); log.debug("Setting StorePool.MaximumSize '" + maxsize + "'"); pool.setMaxActive(maxsize); // 0 = no limit // Set soft maximum - emergency objects (default: false) boolean softmax = PropertyUtils.isTrue(properties, "net.ontopia.topicmaps.impl.rdbms.StorePool.SoftMaximum", false); log.debug("Setting StorePool.SoftMaximum '" + softmax + "'"); if (softmax) pool.setWhenExhaustedAction(GenericObjectPool.WHEN_EXHAUSTED_GROW); else pool.setWhenExhaustedAction(GenericObjectPool.WHEN_EXHAUSTED_BLOCK); } // allow the user to fully overwrite exhausted options String _whenExhaustedAction = PropertyUtils.getProperty(properties, "net.ontopia.topicmaps.impl.rdbms.StorePool.WhenExhaustedAction", false); if (EXHAUSED_BLOCK.equals(_whenExhaustedAction)) pool.setWhenExhaustedAction(GenericObjectPool.WHEN_EXHAUSTED_BLOCK); if (EXHAUSED_GROW.equals(_whenExhaustedAction)) pool.setWhenExhaustedAction(GenericObjectPool.WHEN_EXHAUSTED_GROW); if (EXHAUSED_FAIL.equals(_whenExhaustedAction)) pool.setWhenExhaustedAction(GenericObjectPool.WHEN_EXHAUSTED_FAIL); if (pool.getWhenExhaustedAction() == GenericObjectPool.WHEN_EXHAUSTED_BLOCK) log.debug("Pool is set to block on exhaused"); if (pool.getWhenExhaustedAction() == GenericObjectPool.WHEN_EXHAUSTED_GROW) log.debug("Pool is set to grow on exhaused"); if (pool.getWhenExhaustedAction() == GenericObjectPool.WHEN_EXHAUSTED_FAIL) log.debug("Pool is set to fail on exhaused"); } public synchronized void open() { // ignore if already open if (isOpen()) return; if (isDeleted()) throw new StoreDeletedException("Topic map has been deleted through this reference."); // initialize reference init(); this.isopen = true; } public synchronized TopicMapStoreIF createStore(boolean readonly) { if (!isOpen()) open(); log.debug("RTR: borrow " + getId() + " i: " + pool.getNumIdle() + " a: " + pool.getNumActive()); try { if (readonly) { if (rostore == null) rostore = _createStore(true); else { boolean valid = rostore.validate(); if (!valid) { try { rostore.close(); } catch (Exception e) { } rostore = _createStore(true); } } return rostore; } else { // borrow store from pool and set managed members AbstractTopicMapStore store = (AbstractTopicMapStore) pool.borrowObject(); // register listeners store.setTopicListeners(getTopicListeners()); return store; } } catch (Exception e) { // NOTE: NoSuchElementException will be thrown if pool times out or is // full throw new OntopiaRuntimeException("Could not get topic map store '" + getId() + "' from pool.", e); } } @Override public void setTitle(String title) { super.setTitle(title); TopicMapStoreIF store = null; try { store = createStore(false); TopicMap topicmap = (TopicMap) store.getTopicMap(); topicmap.setTitle(title); store.commit(); } finally { if (store != null) { store.close(); } } } /** * INTERNAL: Returns the base address locator to be used when loading * the topic map. */ public LocatorIF getBaseAddress() { return base_address; } /** * INTERNAL: Sets the base address locator to be used when loading * the topic map and persists it in the database. */ public void setBaseAddress(LocatorIF base_address) { this.base_address = base_address; TopicMapStoreIF store = null; try { store = createStore(false); TopicMap topicmap = (TopicMap) store.getTopicMap(); topicmap.setBaseAddress(base_address); store.commit(); } finally { if (store != null) { store.close(); } } } public synchronized void close() { // ISSUE: should block until all stores are returned to pool? this.isopen = false; if (pool != null) { try { // WARNING: it is important to note that pool does not close // active stores. pool.close(); pool = null; if (rostore != null) { rostore.close(false); rostore = null; } } catch (Exception e) { throw new OntopiaRuntimeException(e); } } } public synchronized void clear() { if (isDeleted()) throw new StoreDeletedException("Topic map has been deleted through this reference."); // close reference close(); // create new topic map store which is to be used when clearing. RDBMSTopicMapStore store = new RDBMSTopicMapStore(storage, topicmap_id); // clear topic map. The store is closed automatically. try { store.clear(); store.commit(); } finally { if (store.isOpen()) store.close(); } } public synchronized void delete() { if (source == null) throw new UnsupportedOperationException( "This reference cannot be deleted as it does not belong to a source."); if (!source.supportsDelete()) throw new UnsupportedOperationException( "This reference cannot be deleted as the source does not allow deleting."); // ignore if store already deleted if (isDeleted()) return; // close reference close(); // create new topic map store which is to be used when deleting. RDBMSTopicMapStore store = new RDBMSTopicMapStore(storage, topicmap_id); // delete topic map from data repository by delegating to // TopicMapStoreIF.close(). The store is closed automatically. this.deleted = store.delete(this); } public String toString() { return super.toString() + " [" + topicmap_id + "]"; } // --- Extension properties public long getTopicMapId() { return topicmap_id; } // --- store pooling public synchronized void storeClosed(TopicMapStoreIF store) { if (!store.isReadOnly()) { // dereference listeners ((AbstractTopicMapStore) store).setTopicListeners(null); } if (pool != null) { log.debug("RTR: return " + getId() + " i: " + pool.getNumIdle() + " a: " + pool.getNumActive()); try { // return rw store to pool if (!store.isReadOnly()) pool.returnObject(store); } catch (Exception e) { throw new OntopiaRuntimeException("Could not return topic map store '" + getId() + "' to pool.", e); } } else { // pool has been closed before store, so we should close store ourselves synchronized (store) { if (store.isOpen()) ((RDBMSTopicMapStore) store).close(false); } } } public void writeReport(java.io.Writer out, boolean dumpCaches) throws java.io.IOException { out.write("<table>\n"); out.write(" <tr><td>"); out.write("Topic Map:"); out.write("</td><td>"); out.write(getId()); out.write(" </td></tr>\n"); out.write(" <tr><td>"); out.write("Active:"); out.write("</td><td>"); out.write(Integer.toString(pool == null ? 0 : pool.getNumActive())); out.write(" </td></tr>\n"); out.write(" <tr><td>"); out.write("Idle:"); out.write("</td><td>"); out.write(Integer.toString(pool == null ? 0 : pool.getNumIdle())); out.write(" </td><tr>\n"); out.write("</table>\n"); Object[] stores = ofactory.stores.toArray(); for (int i = 0; i < stores.length; i++) { RDBMSTopicMapStore store = (RDBMSTopicMapStore) stores[i]; out.write("<h3>Identity Map - ReadWriteStore #"); out.write(Integer.toString(i + 1)); out.write("</h3>\n"); store.writeIdentityMap(out, dumpCaches); } if (rostore != null) { out.write("<h3>Identity Map - ReadOnlyStore</h3>\n"); rostore.writeIdentityMap(out, dumpCaches); } } }