Ramki Technical Blog

In this post i will show Tomcat Clustering in Docker Container. In  my previous post i discussed how to achieve tomcat clustering with Nginx Front end . Its almost same scenario, but this time we will achieve via docker container. Docker Docker  is an  open-source  project that automates the deployment of  applications  inside  software containers , by providing an additional layer of abstraction and automation of  operating-system-level virtualization  on  Linux . [4]  Docker uses resource isolation features of the Linux kernel  such as  cgroups  and kernel  namespaces  to allow independent "containers" to run within a single Linux instance, avoiding the overhead of starting and maintaining  virtual machine   --Wikipedia

In this post i will show the HTML5 Support given by JSF 2.2, Which is part of Java EE 7 Spec. Also how to integrate the Bean Validation 1.1 feature with help of CDI (Contexts and Dependency Injection) 1.1 spec. Before going the HTML5 support, my earlier posts on JSF, i used @ManagedBean annotation, because its part of Managed Bean Specification (Java EE 6). Another Reason i used Tomcat as a primary container, if i used Managed Bean Spec then its part of Mojjara implementation, so no need to add more CDI specific (Jboss Weld lib) lib to class-path. But from Java EE 7 on-wards, JCP community expand the CDI capabilities and make CDI as important spec in Java EE 7 and Managed Bean spec is deprecated in favor of CDI . so they recommend to use CDI wherever its possible. so our future all post to target the CDI. next post i will show how add the CDI capability to tomcat container.

To bring the File Upload feature in Java based web application is one of the difficult and complex job, we need to dependent on 3rd party libraries like Apache Commons FileUpload  Libraries. These libraries codes are complex and most of them boilerplate code. If we are using Java Server Faces (JSF), we have the page with some fields and file upload menu the its add more complexity, fields are binded to backing bean but these file uploads components are need to tie up with some 3rd party file upload libraries. In Primefaces provide easy way to do the file upload in JSF web application, even though primefaces internally used the same Apache Commons FileUpload Libraries, but provide simple JSF tags. We need configure  some listeners.

Recently Java EE 7 specification goes into final. Next week (June 12) oracle going to release the Java EE 7 specification and Glass Fish 4 as reference implementation to general availability. Java EE 7 adds more features like JSF 2.2, Servlet 3.1, Json Processing, websocket support, etc.. click here about the spec. In this post i'm going walk through in JSF 2.2 JSF 2.2 is added more features, and JSF as  a main presentation layer of Java EE platform. compare to JSP, jsp is not getting more feature, they just add maintenance release.

Hi this is my fifth part of the  Tomcat Clustering Series . In this post we are going to discuss how to replace Apache httpd load balancer to Nginx as a load balancer.  [Check the video below for better understanding] Hi i finished Tomcat Clustering Series . In these series we have 2 big setups needed for Tomcat Clustering Setup and configure the Load Balancer Configure the Session Replication in Tomcat. In first setup, we configure the Load Balancer using Apache httpd web server. Its open source and widely used. Second setup is session replication in Tomcat through modify/add <cluster> tag in server.xml file. These tomcat instance may run on single machine or different machine. In our Tomcat Clustering Series , the big part is configure the Load balancer (Apache httpd web server). Because there are lots of steps are involved Install the Apache httpd web server from either source or repo Compile and install the mod_jk connector Create the workers.pr

Hi this is my fourth part of the  Tomcat Clustering Series . In this post we are going to discuss the how to setup session replication using Backup Manager in tomcat clustering environment. Session replication makes High availability and full fail-over capability to our clustering environment. [Check the video below for better understanding] Its continuation of the last post (session replication using Delta Manager) . In delta manager each tomcat instance need to replicate the session information to all other tomcat instances. Its take more time and replication if our cluster size is increased. so there is alternative manager is there. Its Backup Manager. Backup Manager is replicate the copy of session data to exactly one other tomcat instances. This big difference between both managers. here which tomcat creates that is primary copy of the session. and another tomcat whose hold the replicate session is backup copy . If any one of the tomcat is down. back up tomcat serve the ses