Java tutorial
/******************************************************************************* * Copyright (c) 2011 Subgraph. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * Subgraph - initial API and implementation ******************************************************************************/ package com.subgraph.vega.internal.model.alerts; import java.util.Date; import java.util.List; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; import java.util.logging.Logger; import org.apache.http.client.methods.HttpUriRequest; import com.db4o.ObjectContainer; import com.db4o.activation.ActivationPurpose; import com.db4o.activation.Activator; import com.db4o.query.Predicate; import com.db4o.ta.Activatable; import com.subgraph.vega.api.events.EventListenerManager; import com.subgraph.vega.api.events.IEventHandler; import com.subgraph.vega.api.model.alerts.IScanAlert; import com.subgraph.vega.api.model.alerts.IScanInstance; import com.subgraph.vega.api.model.alerts.NewScanAlertEvent; import com.subgraph.vega.api.model.alerts.ScanExceptionEvent; import com.subgraph.vega.api.model.alerts.ScanStatusChangeEvent; import com.subgraph.vega.internal.model.ModelProperties; public class ScanInstance implements IScanInstance, Activatable { private final static Logger logger = Logger.getLogger("alerts"); private final long scanId; private final ModelProperties properties; private final Date startTime; private int scanStatus; private transient EventListenerManager eventManager; private transient ObjectContainer database; private transient ScanAlertFactory alertFactory; private transient Lock lock; private transient int activeScanCompletedCount; private transient int activeScanTotalCount; private transient Activator activator; ScanInstance(long scanId) { this.scanId = scanId; this.scanStatus = SCAN_IDLE; this.properties = new ModelProperties(); this.startTime = new Date(); } void setTransientState(ObjectContainer database, ScanAlertFactory alertFactory) { this.database = database; this.alertFactory = alertFactory; this.lock = new ReentrantLock(); this.eventManager = new EventListenerManager(); } @Override public long getScanId() { activate(ActivationPurpose.READ); return scanId; } @Override public Date getStartTime() { activate(ActivationPurpose.READ); return startTime; } @Override public IScanAlert createAlert(String type) { return createAlert(type, null, -1); } @Override public IScanAlert createAlert(String type, String key) { return createAlert(type, key, -1); } @Override public IScanAlert createAlert(String type, String key, long requestId) { activate(ActivationPurpose.READ); return alertFactory.createAlert(key, type, scanId, requestId); } @Override public void addAlert(IScanAlert alert) { activate(ActivationPurpose.READ); if (rejectDuplicateAlert(alert)) { return; } database.store(alert); eventManager.fireEvent(new NewScanAlertEvent(alert)); } @Override public boolean hasAlertKey(String key) { return getAlertByKey(key) != null; } @Override public IScanAlert getAlertByKey(String key) { if (key == null) { return null; } synchronized (this) { final List<ScanAlert> results = getAlertListForKey(key); if (results.size() == 0) { return null; } if (results.size() > 1) { logger.warning("Multiple alert model entries for key: " + key); } return results.get(0); } } private List<ScanAlert> getAlertListForKey(final String key) { activate(ActivationPurpose.READ); return database.query(new Predicate<ScanAlert>() { private static final long serialVersionUID = 1L; @Override public boolean match(ScanAlert alert) { return key.equals(alert.getKey()) && alert.getScanId() == scanId; } }); } @Override public List<IScanAlert> getAllAlerts() { activate(ActivationPurpose.READ); return database.query(new Predicate<IScanAlert>() { private static final long serialVersionUID = 1L; @Override public boolean match(IScanAlert alert) { return alert.getScanId() == scanId; } }); } @Override public void addScanEventListenerAndPopulate(IEventHandler listener) { lock(); try { for (IScanAlert alert : getAllAlerts()) { listener.handleEvent(new NewScanAlertEvent(alert)); } listener.handleEvent( new ScanStatusChangeEvent(scanStatus, activeScanCompletedCount, activeScanTotalCount)); eventManager.addListener(listener); } finally { unlock(); } } @Override public void removeScanEventListener(IEventHandler listener) { eventManager.removeListener(listener); } @Override public int getScanStatus() { activate(ActivationPurpose.READ); return scanStatus; } @Override public int getScanCompletedCount() { return activeScanCompletedCount; } @Override public int getScanTotalCount() { return activeScanTotalCount; } @Override public void updateScanProgress(int completedCount, int totalCount) { activeScanCompletedCount = completedCount; activeScanTotalCount = totalCount; eventManager .fireEvent(new ScanStatusChangeEvent(scanStatus, activeScanCompletedCount, activeScanTotalCount)); } @Override public void updateScanStatus(int status) { activate(ActivationPurpose.WRITE); this.scanStatus = status; eventManager .fireEvent(new ScanStatusChangeEvent(scanStatus, activeScanCompletedCount, activeScanTotalCount)); } @Override public void notifyScanException(HttpUriRequest request, Throwable exception) { eventManager.fireEvent(new ScanExceptionEvent(request, exception)); } @Override public void lock() { lock.lock(); } @Override public void unlock() { lock.unlock(); } @Override public void setProperty(String name, Object value) { activate(ActivationPurpose.READ); properties.setProperty(name, value); } @Override public void setStringProperty(String name, String value) { activate(ActivationPurpose.READ); properties.setStringProperty(name, value); } @Override public void setIntegerProperty(String name, int value) { activate(ActivationPurpose.READ); properties.setIntegerProperty(name, value); } @Override public Object getProperty(String name) { activate(ActivationPurpose.READ); return properties.getProperty(name); } @Override public String getStringProperty(String name) { activate(ActivationPurpose.READ); return properties.getStringProperty(name); } @Override public Integer getIntegerProperty(String name) { activate(ActivationPurpose.READ); return properties.getIntegerProperty(name); } @Override public List<String> propertyKeys() { activate(ActivationPurpose.READ); return properties.propertyKeys(); } private boolean rejectDuplicateAlert(IScanAlert alert) { if (alert.getResource() == null) { return false; } for (ScanAlert sa : getAlertListForResource(alert.getResource())) { if (sa.equals(alert)) { return true; } } if (alert.getKey() == null) { return false; } else { return hasAlertKey(alert.getKey()); } } private List<ScanAlert> getAlertListForResource(final String resource) { activate(ActivationPurpose.READ); return database.query(new Predicate<ScanAlert>() { private static final long serialVersionUID = 1L; @Override public boolean match(ScanAlert alert) { return resource.equals(alert.getResource()) && alert.getScanId() == scanId; } }); } @Override public void activate(ActivationPurpose activationPurpose) { if (activator != null) { activator.activate(activationPurpose); } } @Override public void bind(Activator activator) { if (this.activator == activator) { return; } if (activator != null && this.activator != null) { throw new IllegalStateException("Object can only be bound to one activator"); } this.activator = activator; } }