When you specify a bean as prototype in xml file or through annotation

<bean
id=”myBeanInstance”
class=”com.xyx.PrototypeBeanExample”
scope=”prototype”
autowire=”byName”>

</bean>

it means that every time a request for this bean is made, a new instance is created. If you want to see the illustration

Prototype bean in Spring

Prototype is meant for beans which hold some state.

The  bean lifecycle also changes in prototype bean. From Spring’s doc

Spring does not manage the complete lifecycle of a prototype bean: the container instantiates, configures, decorates and otherwise assembles a prototype object, hands it to the client and then has no further knowledge of that prototype instance

Problem: For a Oracle (backend) – Java (frontend) system, a query  returning about 500 K rows was running very slow and is taking about 45 mins.  Oracle database is hosted on server (A), has a separate application server (B), and client can access database from client machine (C), using SQLPLUS.  Query is running slow from the clients machine (C) and from the java front end (B).

Basic Checks on dbase:

Make sure to check following with respects to the tables / database in question:

• Latest Database statistics exists for the tables in question.
• Indexes
• Degree of Parallelism at Table Level:
• Optimizer mode

Database configuration parameters  – sga_max_size,  pga_aggregate_target , memory_target, processes Read more…

In this post we will talk about how to integrate hibernate Search into your existing Spring, JPA and Hibernate application and some of the challenges we faced.

We  have a web application using Hibernate (with JPA ) and Spring. This application relies on Spring for transaction, bean initialization / injection etc. EntityManager, transaction are configured in application.xml file. When integrating Hibernate search in such an application one might face problems. In this post I am sharing some problems I faced during integration and the solutions for same.

Entitymanager configuration in my application.xml

Spring configuration:
<bean id=”propertyConfigurer”>
<property name=”location” value=”classpath:myproperties.properties”/>
</bean>

Read more…

Raheel is the guru of Suppy chain management test. He has created  Supply Chain Management Certification practice test for our readers. The test consists of 62 questions.  4 questions are free . The test which usually sells for around $14 , has been priced for $5.99 for a brief period of time. The tests comes with money back guarantee.

Take the test and give your feedback.

Apache JMeter is one of the best open source load testing tools available in market. We had covered Load Testing Using Apache Jmeter in our previous post.

In this post I will go into some more details as how you can read data from csv or text file for Jmeter. This is helpful when you are doing a load test and need unique user id or any other parameter.

CSV Data Set Config settings in Jmeter console

CSV data set in jmeter

This file will reside in bin directory of your Jmeter directory.

userid is the variable you will be using in your url for eg

http://www.abc.com/welcome.jsp&userid=${userid}

How your Myfile.csv file will look like ?

1234
1245
1257

and so on

if you want multiple parameters,  you can have comma separated values like

1234,88
1245,99
1257,44

Java programmers, interested in learning about Scala ? If you have missed our earlier posts on scala

Twitter has been written in which programming language

Why did twitter dumped Ruby on Rails

For new England residents a chance to learn Scala with Venkat Subramaniam who will be presenting on Programming Scala on Aug 12 2010  at  NEJUG.

Venue : Sun Microsystems, Burlington , MA

Dr. Venkat Subramaniam, founder of Agile Developer, Inc., has trained and mentored thousands of software developers in the US, Canada, Europe, and Asia. Venkat helps his clients effectively apply and succeed with agile practices on their software projects, and speaks frequently at international conferences and user groups. He is author of “.NET Gotchas,” coauthor of 2007 Jolt Productivity Award winning “Practices of an Agile Developer,” author of “Programming Groovy: Dynamic Productivity for the Java Developer” and “Programming Scala: Tackle Multi-Core Complexity on the Java Virtual Machine” (Pragmatic Bookshelf).

In our previous posts we had mentioned that Ikoko has added 2 mock test of 50 questions each at Skill-Guru

Spring certification mock test 1

Spring certification mock test 2

These tests are priced at $0.99 each . So how good are the tests ?

Follow this discussion on javaranch to see what real users who have been through Spring certification are saying about the test

Failed Core Spring certification

If you encounter this exception

Caused by: java.lang.SecurityException: class “com.sun.faces.util.FacesLogger”’s signer information does not match signer information of other classes in the same package

at java.lang.ClassLoader.checkCerts(ClassLoader.java:775