Tag Archives: j2ee

Custom CacheProvider for Hibernate based on Websphere DistributedMap

Hibernate is a library that maps database tables to Java objects. Is performance problems arise it's very easy to add database caching for application using Hibernate (just few options in config file). Hibernate is shipped with EHCache, default cache implementation. … Continue reading

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How To Debug JNDI Lookup Problems

Sometimes when you get an exception like this: javax.naming.NameNotFoundException: Name "comp/UserTransaction" not found in context "java:" you want to see what entries are visible in JNDI. No problem, place this code somewhere near lookup problem code location: InitialContext ic = … Continue reading

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Websphere Extreme Scale + Hibernate = ?

Recently I was asked to integrate WXS (Websphere Extreme Scale, commercial cache implementation from IBM) into existing WPS (Websphere Process Server)-based project to implement read-only non-distributed cache (one independent cache instance per JVM). The idea is to plug cache implementation … Continue reading

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Recreate Derby Database Under WebSphere

WebSphere uses SQL databases for internal managment of MQ queues (Derby database engine under the covers). Sometimes you need to reset their state. Here's the script that erase and recreate BPEDB database state (tested under WS 6.1.2): rm -rf $WID_HOME/pf/wps/databases/BPEDB … Continue reading

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Second Level Cache For SQL Queries Under Hibernate

Second level cache in Hibernate allows to greatly speed-up your application by minimizing number of SQL queries issued and serving some results from in-memory cache (with optional disk storage or distributed cache). You have option to plug in different cache … Continue reading

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