Q1. What is JBOSS?
JBoss is a popular open source application server based on JEE technology. Being JEE based, the JBoss supports cross-platform java applications. It was embedded with Apache Tomcat web server. It runs under any JVM of 1.3 or later versions. JBoss supports JNDI, Servlet/JSP (Tomcat or Jetty), EJB, JTS/JTA, JCA, JMS, Clustering (JavaGroups), Web Services (Axis), and IIOP integration (JacORB).
Q2. What is JBoss JBPM?
JBoss JBPM is a workflow and BPM engine. Enabling the creation of business processes that coordinates between people, applications and services is the functionality of BPM engine. The combination of workflow applications development with process design is a feature of JBoss jBPM. The business process is graphically represented to facilitate a strong link between the business analyst and technical developer. This feature is provided by the JBoss jBPM process designer.
Q3. What’s the difference between Standalone mode and Domain mode ?
When configured in Standalone mode each distribution starts a single JVM process with its own configuration, management instruments and deployments. When configured in Domain mode, multiple servers are managed from a centralized point called Domain Controller which maintain the configuration and provisions applications for deployment on the single nodes which are part of the Domain
Q4. What do you need to set-up a cluster with JBoss ?
Basically starting JBoss with the “all” configuration contains everything needed for clustering:
It has all the libraries for clustering:
Clustered beans (cluster-service.xml)
HTTP session replications (tc5-cluster-service.xml)
Q5. How do you monitor JBoss and detect the bottleneck of an application?
Different components of the application are to be measured. This step is to find where the degradation is, whether it is external or internal and where is the appliciation spending all the time. Using Joss JMX agents and monitoring the deployed components to the application server involves in the first step.
After finding the most of the time spent by specific components or libraries or most of the resources, one can use Jprobe a specialized tool for examining the single object or the objects loaded in the memory.
Q6. Is it possible to put a JBoss server instance into multiple cluster at the same time ?
It is technically possible to put a JBoss server instance into multiple clusters at the same time, this practice is generally not recommended, as it increases the management complexity.
Q7. Does Seam run on other application servers besides JBoss ?
Seam runs beautifully on other application servers – just like everything else the Hibernate team does, this is not a JBoss-only thing.
Q8. What’s jBoss cache in short ?
JBossCache enables easy distribution of datasets across your computing environments. It is based on JGroups and enables clustering and high availability of that data. You may choose to distribute the data with JBoss Messaging to move it where it is needed for computation or event-based programming
Q9. Which Hibernate object wraps the JDBC Connection?
The Session interface wraps a JDBC Connection. This interface is a single threaded object which represents a single unit of work with application and persistent database. It’s retrieved by the SessionFactory’s openSession() method
Q10. How can you start a JTA transaction from a Servlet deployed on JBoss?
JBoss registers in the JNDI tree a JTA UserTransaction Object which can be user to manage a distributed transaction.