Cache Expiration

Question

Hi,
Can any one let me know how to set cache expiration based on access time instead of the inserted time.
Or is there any way to identify the Cache Expiry value of an existing entry.
I am using Coherence 3.4. and I need to reset the expiry time for the ones which was inserted with a expiry value each time I access it.
It would be great if some one can help to figure this out.
Thanks!

Answer 1

Hi user2030814,
If you want to set expiration time based on last access instead of insert/modify time you can do something like this:
<?xml version="1.0"?>
<!DOCTYPE cache-config SYSTEM "cache-config.dtd">
<cache-config>
    <caching-scheme-mapping>
        <cache-mapping>
            <cache-name>test</cache-name>
            <scheme-name>test</scheme-name>
        </cache-mapping>
    </caching-scheme-mapping>
    <caching-schemes>
        <distributed-scheme>
            <scheme-name>test</scheme-name>
            <backing-map-scheme>
                <local-scheme>
                    <class-name>MyLocalScheme</class-name>
                    <expiry-delay>2s</expiry-delay>
                    <flush-delay>1s</flush-delay>                   
                </local-scheme>
            </backing-map-scheme>
        </distributed-scheme>
    </caching-schemes>
</cache-config>
import com.tangosol.net.cache.CacheLoader;
import com.tangosol.net.cache.LocalCache;
import com.tangosol.net.CacheFactory;
import com.tangosol.net.NamedCache;
import com.tangosol.util.SafeHashMap;
import com.tangosol.util.Base;
* dimitri
public class MyLocalScheme extends LocalCache
    public MyLocalScheme()
        super();
    public MyLocalScheme(int cUnits)
        super(cUnits);
    public MyLocalScheme(int cUnits, int cExpiryMillis)
        super(cUnits, cExpiryMillis);
    public MyLocalScheme(int cUnits, int cExpiryMillis, CacheLoader loader)
        super(cUnits, cExpiryMillis, loader);
    protected SafeHashMap.Entry instantiateEntry()
        return new MyEntry();
    public class MyEntry extends LocalCache.Entry
        public void touch()
            super.touch();
            setExpiryMillis(getSafeTimeMillis() + getExpiryMillis());
            scheduleExpiry();
    // test harness
    public static void main(String[] asArg)
        try
            NamedCache cache = CacheFactory.getCache("test");
            cache.put("foo", "bar");
            // keep reading the entry which will reset expiration time
            for (int i = 0; i < 10; i++)
                Thread.sleep(1500l);
                CacheFactory.log("Entry in the cache: " + cache.get("foo"), CacheFactory.LOG_DEBUG);
            // now let it expire
            Thread.sleep(2500l);
            CacheFactory.log("Entry in the cache: " + cache.get("foo"), CacheFactory.LOG_DEBUG);
        catch (Throwable oops)
            Base.err(oops);
        finally
            CacheFactory.shutdown();
    }Regards,
Dimitri