A Quick update, I tried this with low level google api and that seems to work perfectly fine and i am able to retrieve values from the existing cache and don't load it from db everytime hence reduces my jvm restart load time by 3-4 seconds.
Not sure what jsr 107 was not working. Thanks, Rahul On May 25, 10:24 pm, Rahul <[email protected]> wrote: > Ikai, > > I am guessing i am wrong somewhere in designing this cache solution. > Would appreciate if you can tell me where am i going wrong on this. > Let me try to explain it once again. > > I have a set of properties which i load on first call to the service. > and the code I call in the service is as follows. > > PropertiesCache _cache = PropertiesCache.getInstance(); > > My PropertiesCache is as follows. > ------------------------------------------------------------------- > public class PropertiesCache { > private static final Logger log = > Logger.getLogger(PropertiesCache.class.getName()); > > private static PropertiesCache _instance; > private Cache cache; > private PropertiesCache() { > try { > log.info("In the PropertiesCache constructor"); > cache = > CacheManager.getInstance().getCacheFactory().createCache(Collections.emptyMap()); > //Loading the cache from the database. > //cache.put(Object, Object); > } catch (CacheException e) { > log.severe("Error in creating the Loading Cache"); > } > > public static synchronized PropertiesCache getInstance() { > if (_instance == null) { > _instance = new PropertiesCache(); > }else{ > log.info("Using existing cache instance and NO NEW > Instance is > created"); > } > > return _instance; > } > > Also, Let me re-iterate what you said, you are suggesting me not to > play around with instance variable instead use the cache variable and > is there any way i can fetch the cache variable once the jvm restarts. > > Appreciate all the efforts. > > Thanks, > Rahul > On May 25, 5:08 pm, "Ikai L (Google)" <[email protected]> wrote: > > > The instance itself will be recreated. If you store a value into Memcache, > > it will likely be there the next time you retrieve it. Try this out. > > > It's not necessary to do what you've done here. When you create a Cache > > instance, you're really just creating a client to the cache, and you can do > > this each time you need it. There's no need to create a global, long-lived > > instance. What you're seeing is perfectly normal - Java objects will not > > have a longer lifespan than the JVM. If the JVM dies, so will all the > > instantiated objects. > > > On Tue, May 25, 2010 at 1:28 PM, Rahul <[email protected]> wrote: > > > Toby, > > > > I also had the same opinion but as you can see the previous code i > > > have given populates the cache again. I guess i am doing something > > > wrong. Appreciate if you can look at that and let me know if i have to > > > do something which i missing. > > > > Thanks, > > > Rahul > > > > On May 25, 4:00 pm, Toby Reyelts <[email protected]> wrote: > > > > Rahul, > > > > > If you're using App Engine's MemcacheService directly (or indirectly, > > > > for > > > > example through our JSR 107 support), then you are talking to backend > > > > memcache instances that have lifetimes separate from your JVMs. > > > > > I.E. MemcacheServiceFactory.getMemcacheService< > > >http://code.google.com/appengine/docs/java/javadoc/com/google/appengi...() > > > > > does > > > > not create a new memcache backend - it just "connects" to an existing > > > one. > > > > You have one logical memcache backend that is shared between all of your > > > > application's JVMs. > > > > > On Tue, May 25, 2010 at 3:12 PM, Rahul <[email protected]> wrote: > > > > > Ikai, > > > > > > I am not sure what you mean by Memcache instances stays up because i > > > > > tried the following code and everytime when a new jvm instance is > > > > > created, the cache instance is also created again. Below is the code i > > > > > am using, let me know if i am missing anything or not doing anything > > > > > correct. > > > > > > Request comes from the following code: > > > > > > MyCache _cache = MyCache.getInstance(); > > > > > redirectUrl = _cache.findInCache(requestedURI); > > > > > > MyCache Class: > > > > > > private static MyCache _instance; > > > > > private Cache cache; > > > > > > public static synchronized MyCache getInstance() { > > > > > if (_instance == null) { > > > > > _instance = new MyCache(); > > > > > }else{ > > > > > log.info("Using existing cache instance and NO > > > NEW > > > > > Instance is > > > > > created"); > > > > > } > > > > > > return _instance; > > > > > } > > > > > > and in the constructor i am creating new cache fetching everything > > > > > from the database. > > > > > > Also, i have a listener in place which tells me when the new jvm > > > > > instance is started. > > > > > > Thanks, > > > > > Rahul > > > > > > On May 24, 3:56 pm, "Ikai L (Google)" <[email protected]> wrote: > > > > > > Memcache instances stay up. They're shared, namespaced (security) > > > > > instances > > > > > > and will more likely than not outlive the lifecycles of your > > > application > > > > > > instances. > > > > > > > On Sun, May 23, 2010 at 11:17 PM, Tristan < > > > [email protected] > > > > > >wrote: > > > > > > > > Does anyone know the answer to this: > > > > > > > > If all the JVMs are killed, does the memcache stick around or is > > > > > > > it > > > > > > > recycled? (I know memcache expires eventually, just curious if it > > > is > > > > > > > possible for it to carry data across JVM valley of death) > > > > > > > > Cheers, > > > > > > > > Tristan > > > > > > > > -- > > > > > > > You received this message because you are subscribed to the Google > > > > > Groups > > > > > > > "Google App Engine for Java" group. > > > > > > > To post to this group, send email to > > > > > > > [email protected]. > > > > > > > To unsubscribe from this group, send email to > > > > > > > [email protected]<google-appengine-java%[email protected]><google-appengine-java%2B > > > [email protected]><google-appengine-java%2B > > > > > [email protected]> > > > > > > > . > > > > > > > For more options, visit this group at > > > > > > >http://groups.google.com/group/google-appengine-java?hl=en. > > > > > > > -- > > > > > > Ikai Lan > > > > > > Developer Relations, Google App Engine > > > > > > Twitter:http://twitter.com/ikai > > > > > > Delicious:http://delicious.com/ikailan > > > > > > > ---------------- > > > > > > Google App Engine links: > > > > > > Blog:http://googleappengine.blogspot.com > > > > > > Twitter:http://twitter.com/app_engine > > > > > > Reddit:http://www.reddit.com/r/appengine > > > > > > > -- > > > > > > You received this message because you are subscribed to the Google > > > Groups > > > > > "Google App Engine for Java" group. > > > > > > To post to this group, send email to > > > > > [email protected]. > > > > > > To unsubscribe from this group, send email to > > > > > [email protected]<google-appengine-java%[email protected]><google-appengine-java%2B > > > [email protected]> > > > > > . > > > > > > For more options, visit this group athttp:// > > > > > groups.google.com/group/google-appengine-java?hl=en. > > > > > > -- > > > > > You received this message because you are subscribed to the Google > > > Groups > > > > > "Google App Engine for Java" group. > > > > > To post to this group, send email to > > > > > [email protected]. > > > > > To unsubscribe from this group, send email to > > > > > [email protected]<google-appengine-java%[email protected]><google-appengine-java%2B > > > [email protected]> > > > > > . > > > > > For more options, visit this group at > > > > >http://groups.google.com/group/google-appengine-java?hl=en. > > > > -- > > > You received this message because you are subscribed to the Google Groups > > > "Google App Engine for Java" group. > > > To post to this group, send email to > > > [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected]<google-appengine-java%[email protected]> > > > . > > > For more options, visit this group at > > >http://groups.google.com/group/google-appengine-java?hl=en. > > > -- > > Ikai Lan > > Developer Programs Engineer, Google App Engine > > Twitter:http://twitter.com/ikai > > Delicious:http://delicious.com/ikailan > > > ---------------- > > Google App Engine links: > > Blog:http://googleappengine.blogspot.com > > Twitter:http://twitter.com/app_engine > > Reddit:http://www.reddit.com/r/appengine > > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. 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