This article describes some complementation for Open Session In View pattern for Java/Spring. But first I want to show just my point of view about the pattern itself. Many people consider this as an anti-pattern and tell that it never should be used. I think exactly opposite, and here are some explanations.

My way to reflect permission system implemented on database/ORM level in full text indexing system based on Lucene.

Today my target was to implement various connections for POP3/SMTP email accounts. incuding:

• plain connection with no encryption
• STARTTLS
• SSL/TSL

The key requirement here was to have it without java keystore file configured for storing and accepting server certificates. This should work transparently for the user.

If you have a Spring 2 application using MuleESB in 2.x version, and you initialize the mule using SpringXmlConfigurationBuilder, you may notice that this simply doesn’t work in Spring 3 ;)

I’ve recently had a requirement of setting up the application to work in high-availability environment, which among the others involved hardiness for database (mysql) crash. We established with the customer that we want to have a second database server, where the mysql database mirror will be maintained using master-slave mysql replication. In this model the master mysql server takes care of synchronizing records from itself to the slave server, and the slave server is available in fail-scenario for the application in read-only mode.

Some time ago I wrote few words about some dynamic forms implementation methods using LazyList or AutoPopulatingList with items removing. The problem that interested me today was related to this subject, but concerned something else: how to implement dynamic forms in the way, so that it can be used transparently for any object (even a Hibernate entity) without creating specialized form beans for that.

In the production environment web application debuging is not so easy. Especially because when multiple users perform multiple actions in the same time, the output log is interleaved, and the step-by-step situation is hard to reproduce in development lab. The solution for that can be by injecting user name into the log, and then “grepping” the source log in looking for particular user paths.

If you look for the way of making your expensive algorithm faster, you may consider multithreading and concurrency. You can divide your data into the parts and start threads to handle each part concurrently. This looks easy but sometimes there are some additional requisites that you need to obey doing that.

Solving some interesting problems in the project I’m currently working on I started to analyse following problem: you have a large data set (eg. a file) on which you need to apply some expensive transformation (eg. compression). The key requirement is a performance.

If you’d like to check how to apply the dynamic form binding to any object (even for Hibernate entities) check my another post.

Browsing internet you can easily find a common method of implementing dynamic forms in JEE world. This is usually done using LazyList from apache commons-collections, or AutoPopulatingList from Spring. I don’t want to repeat these descriptions, you can find nice examples here (using LazyList) or here (using AutoPopulatingList).