Tomcat remote debugging

You can debug remote server for example from eclipse using JPDA.

Java implement a web service client

Exist two common ways to create webservice client in java it's Axis 2 or JAX-WS. What is the best approach? here is performance comparison, it says that JAX-WS is much better (about twice). Below is the comparison table.

Specified VM install not found: type Standard VM, name jre6

Ant saying "Specified VM install not found: type Standard VM, name jre6"! Solution is to delete the "C:\Users\Sergey\juno\.metadata\.plugins\org.eclipse.debug.core\.launches\projectname build.xml.launch file"

Configuring Log4j with Java Web Applications + Tomcat

Log4j -  is a Java-based logging utility. Next i will explain hot to configure it with Web App + tomcat.

JVM Performance Tuning

while(iAmNotSatisfied){  
   size = defineMinMaxHeapSize();
   ratios =  tuneGenerationRatios();
   alg = selectAppropriateGcAlgorithm();
   testApplication(size, ratios, alg);
   iAmNotSatisfied = analyzeStatistics();
}
More details later...;)

References:
From Vladislav Gangan Software as Craft presentation
Books:
Java Performance Tuning (2nd Edition)
Pro Java EE 5 Performance Management and Optimization
Java Performance

Java HotSpot VM Options

Useful Linux commands

Some Useful Linux Commands

Configuring VisualVM with tomcat + linux

VisualVM is a tool that provides a visual interface for viewing detailed information about Java applications while they are running on a Java Virtual Machine (JVM), and for troubleshooting and profiling these applications.

Spring Security authentication failure event

For security reasons you need to limit failure login attempts in your application, simply you can do it using counter, that updates a count in the DB. Next I will show how to handle this event in Spring Security

Java: MongoDB simple example

MongoDB - is an open source document-oriented NoSQL database system. Next I will create simple servlet example that's uses MongoDB. 

Java: Generate Microsoft Word document

First you need download Apache POI - the Java API for Microsoft Documents, and next this fragment of code

Java Concurrent Animated

This project is a series of animations each illustrating the coding and usage of a component in the java concurrent library.

Comparing JVM WEB Frameworks

OWASP Top Ten Web-sites Security leaks

• A1: Injection
• A2: Cross-Site Scripting (XSS)
• A3: Broken Authentication and Session Management
• A4: Insecure Direct Object References
• A5: Cross-Site Request Forgery (CSRF)
• A6: Security Misconfiguration
• A7: Insecure Cryptographic Storage
• A8: Failure to Restrict URL Access
• A9: Insufficient Transport Layer Protection
• A10: Unvalidated Redirects and Forwards

Source:
Link

C3P0 ConnectionPool: How To configure

C3P0 - is a connection pool,  connection pool is a cache of database connections maintained, so that the connections can be reused when future requests to the database are required. 

The main question is how to cofigure it, because default values are not perfect. First of all I found oficial doc with description of the values. Next I found this one C3P0 ConnectionPool Configuration Rules of Thumb. After some performance testing of my application, I can confirm that configuring like in this article, can greatly increase your performance, in my case it was about twice. So bellow text of this article -  "