*/
public class BackUpMonitor {
private static final Logger LOGGER = Logger.getLogger(BackUpMonitor.class.getName());
- private static final int DEFAULT_PING = 15000; // Value is in milliseconds.
-
+ private static final int DEFAULT_PING = 500; // Value is in milliseconds.
+ private static final String PING_INTERVAL = "ping_interval";
+ private static final String MASTER = "MASTER";
+ private static final String SLAVE = "SLAVE";
+
private static BackUpMonitor instance = null;
private static String resourceName = null;
private static String resourceNodeName = null;
private static Object lock = new Object();
private static Object notificationLock = new Object();
private static BackUpHandler handler = null;
+ private static Boolean stopFlag = false;
+ private static Thread t = null;
private EntityManager em;
private EntityManagerFactory emf;
private BackUpMonitor(String resourceNodeName, String resourceName, Properties properties, BackUpHandler handler)
throws BackUpMonitorException {
- if (instance == null) {
- instance = this;
- }
- BackUpMonitor.resourceNodeName = resourceNodeName;
- BackUpMonitor.resourceName = resourceName;
- BackUpMonitor.handler = handler;
+ init(resourceName, resourceNodeName, handler);
// Create Persistence Entity
- properties.setProperty(PersistenceUnitProperties.ECLIPSELINK_PERSISTENCE_XML, "META-INF/persistencePU.xml");
+ if(!properties.containsKey(PersistenceUnitProperties.ECLIPSELINK_PERSISTENCE_XML)){
+ properties.setProperty(PersistenceUnitProperties.ECLIPSELINK_PERSISTENCE_XML, "META-INF/persistencePU.xml");
+ }
emf = Persistence.createEntityManagerFactory("PolicyEngineUtils", properties);
if (emf == null) {
LOGGER.error("Unable to create Entity Manger Factory ");
// Check Database if this is Master or Slave.
checkDataBase();
-
// Start thread.
- Thread t = new Thread(new BMonitor());
+ startThread(new BMonitor());
+ }
+
+ private static void startThread(BMonitor bMonitor) {
+ t = new Thread(bMonitor);
t.start();
}
+ public static void stop() throws InterruptedException{
+ stopFlag = true;
+ if(t!=null){
+ t.interrupt();
+ t.join();
+ }
+ instance = null;
+ }
+
+ private static void init(String resourceName, String resourceNodeName, BackUpHandler handler) {
+ BackUpMonitor.resourceNodeName = resourceNodeName;
+ BackUpMonitor.resourceName = resourceName;
+ BackUpMonitor.handler = handler;
+ stopFlag = false;
+ }
+
/**
* Gets the BackUpMonitor Instance if given proper resourceName and properties. Else returns null.
*
LOGGER.error("javax.persistence.jdbc.user property is empty");
return false;
}
- if (properties.getProperty("javax.persistence.jdbc.password") == null
- || properties.getProperty("javax.persistence.jdbc.password").trim().equals("")) {
- LOGGER.error("javax.persistence.jdbc.password property is empty");
- return false;
- }
- if (properties.getProperty("ping_interval") == null
- || properties.getProperty("ping_interval").trim().equals("")) {
+ if (properties.getProperty(PING_INTERVAL) == null
+ || properties.getProperty(PING_INTERVAL).trim().equals("")) {
LOGGER.info("ping_interval property not specified. Taking default value");
} else {
try {
- pingInterval = Integer.parseInt(properties.getProperty("ping_interval").trim());
+ pingInterval = Integer.parseInt(properties.getProperty(PING_INTERVAL).trim());
} catch (NumberFormatException e) {
LOGGER.warn("Ignored invalid proeprty ping_interval. Taking default value: " + pingInterval);
pingInterval = DEFAULT_PING;
@Override
public void run() {
LOGGER.info("Starting BackUpMonitor Thread.. ");
- while (true) {
+ while (!stopFlag) {
try {
TimeUnit.MILLISECONDS.sleep(pingInterval);
checkDataBase();
// Set Master
private static BackUpMonitorEntity setMaster(BackUpMonitorEntity bMEntity) {
- bMEntity.setFlag("MASTER");
+ bMEntity.setFlag(MASTER);
setFlag(true);
return bMEntity;
}
// Set Slave
private static BackUpMonitorEntity setSlave(BackUpMonitorEntity bMEntity) {
- bMEntity.setFlag("SLAVE");
+ bMEntity.setFlag(SLAVE);
setFlag(false);
return bMEntity;
}
// Check Database and set the Flag.
private void checkDataBase() throws BackUpMonitorException {
- EntityTransaction et = em.getTransaction();
- setNotificationRecord();
- // Clear Cache.
- LOGGER.info("Clearing Cache");
- em.getEntityManagerFactory().getCache().evictAll();
+ EntityTransaction et = null;
try {
+ et = em.getTransaction();
+ setNotificationRecord();
+ // Clear Cache.
+ LOGGER.info("Clearing Cache");
+ em.getEntityManagerFactory().getCache().evictAll();
LOGGER.info("Checking Datatbase for BackUpMonitor.. ");
et.begin();
Query query = em.createQuery("select b from BackUpMonitorEntity b where b.resourceNodeName = :nn");
BackUpMonitorEntity bMEntity = (BackUpMonitorEntity) bMList.get(i);
LOGGER.info("Refreshing Entity. ");
em.refresh(bMEntity);
- if (bMEntity.getFlag().equalsIgnoreCase("MASTER")) {
+ if (bMEntity.getFlag().equalsIgnoreCase(MASTER)) {
masterEntities.add(bMEntity);
}
if (bMEntity.getResourceName().equals(resourceName)) {
}
if (selfEntity != null) {
LOGGER.info("Resource Name already Exists: " + resourceName);
- if (selfEntity.getFlag().equalsIgnoreCase("MASTER")) {
+ if (selfEntity.getFlag().equalsIgnoreCase(MASTER)) {
// Already Master Mode.
setFlag(true);
LOGGER.info(resourceName + " is on Master Mode");
// Slave.
BackUpMonitorEntity masterEntity = null;
for (BackUpMonitorEntity currentEntity : masterEntities) {
- if (currentEntity.getFlag().equalsIgnoreCase("MASTER")) {
+ if (currentEntity.getFlag().equalsIgnoreCase(MASTER)) {
if (masterEntity == null) {
masterEntity = currentEntity;
} else if (currentEntity.getTimeStamp().getTime() > masterEntity.getTimeStamp()
.getTime()) {
// False Master, Update master to slave and take currentMaster as Master.
- masterEntity.setFlag("SLAVE");
+ masterEntity.setFlag(SLAVE);
masterEntity.setTimeStamp(new Date());
em.persist(masterEntity);
em.flush();
masterEntity = currentEntity;
} else {
- currentEntity.setFlag("SLAVE");
+ currentEntity.setFlag(SLAVE);
currentEntity.setTimeStamp(new Date());
em.persist(currentEntity);
em.flush();
if (timeDiff > (pingInterval + 1500)) {
// This is down or has an issue and we need to become Master while turning the
// Master to slave.
- masterEntity.setFlag("SLAVE");
+ masterEntity.setFlag(SLAVE);
String lastNotification = null;
if (masterEntity.getNotificationRecord() != null) {
lastNotification = calculatePatch(masterEntity.getNotificationRecord());
et.commit();
} catch (Exception e) {
LOGGER.error("failed Database Operation " + e.getMessage(), e);
- if (et.isActive()) {
+ if (et!=null && et.isActive()) {
et.rollback();
}
throw new BackUpMonitorException(e);
Code Review / policy / engine.git / blobdiff