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 JAR –tf <filename.jar>

 jar –tf <filename.jar>

• TAR – derived from tape archive is a file format to archive bitstreams and name of a PROGRAM to handle such files. It is commonly USED to COLLECT many files into one large file for distributing or archiving while PRESERVING the FILESYSTEM info.
• WAR – web application archive is a jar file used to distribute a collection of JavaServer Pages, Java Servlets, Java classes, xml files, tag libraries, static web pages (html & others) and others resources that constitute a web application.

• WAR – web application archive is a jar file used to distribute a collection of JavaServer Pages, Java Servlets, Java classes, xml FILES, tag libraries, static web pages (html &AMP; others) and others resources that constitute a web application.
• JAR – Java Archive, is an archive file format typically used to aggregate many Java class files and ASSOCIATED metadata and resources into one file to distribute application software, libs on the Java platform.
• EAR – Enterprise Archive is used to PACKAGE one or more moduels into a single archive so the deployment of the various modules into app server happen simultaneiously and coherently.

The following directories are available after JBoss is installed.

• MODULES
• BUNDLES
• domain
• standalone
• appclient
• bin
• docs
• welcome-content

The following directories are available after JBoss is installed.

There is five POSSIBLE level:

1. FATAL
2. ERROR
3. WARN
4. INFO
5. DEBUG

There is five possible level:

JBOSS clustering is on top of JGroups toolkit which helps to create, delete, membership DETECTION, NOTIFICATION, etc. in the cluster.

JBoss clustering is on top of JGroups toolkit which helps to create, delete, membership detection, notification, etc. in the cluster.

JBoss installation is very STRAIGHTFORWARD. You need to download the desired version from JBoss official download PAGE in zip or gz format.

Once downloaded, just extract the file to the location you WANT to INSTALL. If you downloaded zip format, then you can use unzip command to extract it.

unzip jboss-as-7.1.1.Final.zip

JBoss installation is very straightforward. You need to download the desired version from JBoss official download page in zip or gz format.

Once downloaded, just extract the file to the location you want to install. If you downloaded zip format, then you can use unzip command to extract it.

unzip jboss-as-7.1.1.Final.zip

9990 is the DEFAULT PORT. If it’s installed on SERVER1 then you NEED to access like:
http://server1:9990/admin-console

9990 is the default port. If it’s installed on server1 then you need to access like:
http://server1:9990/admin-console

The USER must be created under “ManagementRealm” to have console OPERATIONAL. To CREATE the user, you can go to bin folder and EXECUTE add-user.sh script.

The user must be created under “ManagementRealm” to have console operational. To create the user, you can go to bin folder and execute add-user.sh script.

GO to BIN folder where JBOSS is installed and start with the FOLLOWING COMMAND.

./standalone.sh

Go to bin folder where JBoss is installed and start with the following command.

./standalone.sh

Heap Memory can be INCREASED in a respective conf file. To increase memory for STANDALONE;

• Go to bin folder
• Edit the standalone.conf file and look for “JAVA_OPTS=” argument LINE
• The DEFAULT configuration will have minimum 64 MB and maximum 512 MB. You can increase to the desired value.
• Xms – specify the minimum heap size.
• Xmx – specify the maximum heap size.

In a similar WAY, you can adjust the memory for a domain in domain.conf file

Heap Memory can be increased in a respective conf file. To increase memory for standalone;

In a similar way, you can adjust the memory for a domain in domain.conf file

• Standalone mode is single JVM process where EVERY JBoss server has its configuration. If you just need one JVM or development environment, then standalone would be perfect.
• Domain mode may have multiple SERVERS where all configuration is managed centralized and often used in production environment.

Yes, CLUSTERING is POSSIBLE in STANDALONE mode. However, an application MUST be deployed on each server/JVM in standalone mode.

Yes, clustering is possible in standalone mode. However, an application must be deployed on each server/JVM in standalone mode.

• <validate-on-match> validate the database CONNECTION every time, and if a connection is not valid, it will write a WARNING in the logs.
• Having “validate-on-match” CONFIGURED may have a little high load on the database as it may create lots of requests.
• <background-validation> validate the connection periodically based on what frequency is configured for “background-validation-millis”. The default configuration is set to zero means disabled.
• Having “ background-validation” set to true will create fewer database connections and it’s side-effects would be not DETECTING immediately if dead connections.

There are two MODULES you can use to connect JBOSS with APACHE.

• mod_proxy.
• mod_jk.

There are two modules you can use to connect JBoss with Apache.

You can deploy almost any kind of JAVA/J2EE application, and it SUPPORTS the following file FORMAT.

• WAR: Web application ARCHIVE
• SAR: Service archive
• JAR: Java Archive
• EAR: ENTERPRISE application archive

You can deploy almost any kind of Java/J2EE application, and it supports the following file format.

There are three POSSIBLE ways to deploy an application in JBoss application server.

1. Admin CONSOLE – you can deploy the NECESSARY application files through the administration console.
2. Auto-deploy – leverage file SYSTEM deployment scanner to auto deploy files from deployments folder.
3. Automation – use automation tool/ant/scripting to deploy an application.

There are three possible ways to deploy an application in JBoss application server.

.dodeploy FILE SUFFIX is NEEDED for JBOSS to DEPLOY or redeploy an application.
For ex: myfirstapplication.war.dpdeploy

.dodeploy file suffix is needed for JBoss to deploy or redeploy an application.
For ex: myfirstapplication.war.dpdeploy

• .dodeploy – instruct to deploy
• .DEPLOYED – INDICATE the file is deployed
• .pending – deployment is still pending
• .undeployed – confirmation that APPLICATION is undeployed
• .failed – deployment is failed for some reason
• .skipdeploy – instruct JBOSS to ignore the files for auto-deployment

All ADMIN CONSOLE USERS and password (ENCRYPTED) are STORED in mgmt.-user.properties file.

All admin console users and password (encrypted) are stored in mgmt.-user.properties file.

 Choose the server profile to which you want to DEPLOY the APPLICATION

• Copy your application (for example: .war or .ear or a .JAR file) to JBOSS_HOME/server/<profilename>/deploy folder.
• START the server: (./run.sh)
• JBoss will deploy your application when it boots up.

 Choose the server profile to which you want to deploy the application

JBoss Enterprise Application PLATFORM is an OPEN source IMPLEMENTATION of the Java EE suite of SERVICES

JBoss Enterprise Application Platform is an open source implementation of the Java EE suite of services

• To enable, put file hdscanner-jboss-beans.xml in JBOSS_HOME/server/<profilename&GT;/DEPLOY
• To disable hot DEPLOYMENT, REMOVE the hdscanner-jboss-beans. xml from the deploy folder or rename it to hdscanner-jbossbeans. xml.BAK (.bak files are ignored).

JBoss has a built-in hot DEPLOYER which can:

• Detect new applications in the deploy FOLDER and trigger an APPLICATION deployment
• Detect an application which was removed from the deploy folder and trigger an application undeployment
• Detect that the deployment descriptor of an application (for EXAMPLE, the web.xml of .war or application.xml of .EAR) has changed and trigger an application redeployment

JBoss has a built-in hot deployer which can:

Seam only supports JSF as a view framework at this time. We plan to support other web frameworks in the future. We like JSF because it is a component-based UI framework, which fits REALLY WELL with Seam’s component-based approach to business OBJECTS and persistence objects. Seam made a MAJOR improvement to JSF by eliminating almost all XML configuration for backing beans — you can now DEFINE back beans from POJOs or EJB3 components using simple annotations.

We recommend you use Facelets, instead of JSP, with JSF. Facelets provide a powerful templating framework, better appplication performance, and allows us to write much simpler JSF pages. Please see the Seam booking example application for an example on how to use Facelets.

Seam only supports JSF as a view framework at this time. We plan to support other web frameworks in the future. We like JSF because it is a component-based UI framework, which fits really well with Seam’s component-based approach to business objects and persistence objects. Seam made a major improvement to JSF by eliminating almost all XML configuration for backing beans — you can now define back beans from POJOs or EJB3 components using simple annotations.

We recommend you use Facelets, instead of JSP, with JSF. Facelets provide a powerful templating framework, better appplication performance, and allows us to write much simpler JSF pages. Please see the Seam booking example application for an example on how to use Facelets.

For Seam 1.3: Seam was developed against JBoss 4.2. Seam can still be run against JBoss 4.0. The seam documentation CONTAINS instructions for configuring JBoss 4.0.

For Seam 1.2: Since Seam requires the latest EDITION of EJB3, you need to INSTALL JBoss AS from the latest JEMS installer. Make sure that you select the “ejb3” or “ejb3+clustering” profile to include EJB3 support. Also, the jboss-seam.jar library file from the Seam distribution must be included in each Seam application you deploy. 

For Seam 1.3: Seam was developed against JBoss 4.2. Seam can still be run against JBoss 4.0. The seam documentation contains instructions for configuring JBoss 4.0.

For Seam 1.2: Since Seam requires the latest edition of EJB3, you need to install JBoss AS from the latest JEMS installer. Make sure that you select the “ejb3” or “ejb3+clustering” profile to include EJB3 support. Also, the jboss-seam.jar library file from the Seam distribution must be included in each Seam application you deploy. 

JBossTS supports Web Services transactions, including extended transaction models designed specifically for loosely-coupled, long running BUSINESS processes. J2EE transactions can integrate seamlessly with Web Services transactions using our INTEGRATED, bi-directional transaction bridge. Interoperability with many other vendors is PROVIDED out-of-the-box and JBoss is an active participant in these STANDARDS.

JBossTS supports Web Services transactions, including extended transaction models designed specifically for loosely-coupled, long running business processes. J2EE transactions can integrate seamlessly with Web Services transactions using our integrated, bi-directional transaction bridge. Interoperability with many other vendors is provided out-of-the-box and JBoss is an active participant in these standards.

Java API for XML-Based RPC (JAX-RPC) is a LEGACY Web Services Java API, it uses SOAP and HTTP to do RPCs over the network and enables building of Web services and Web applications based on the SOAP 1.1 specification, Java SE 1.4 or lower.JAX-WS 2.0 is the successor to JAX-RPC 1.1. JAX-WS still supports SOAP 1.1 over HTTP 1.1, so interoperability will not be affected. However there are lots of differences:

• JAX-WS maps to Java 5.0 and relies on many of the features new in Java 5.0 like Web SERVICE annotations.
• JAX-RPC has its own data mapping model, JAX-WS’s data mapping model is JAXB. JAXB PROMISES mappings for all XML schemas.
• JAX-WS introduces message-oriented functionality, dynamic asynchronous functionality which are missing in JAX-RPC.
• JAX-WS ALSO add support, via JAXB, for MTOM, the new attachment specification.

Java API for XML-Based RPC (JAX-RPC) is a Legacy Web Services Java API, it uses SOAP and HTTP to do RPCs over the network and enables building of Web services and Web applications based on the SOAP 1.1 specification, Java SE 1.4 or lower.JAX-WS 2.0 is the successor to JAX-RPC 1.1. JAX-WS still supports SOAP 1.1 over HTTP 1.1, so interoperability will not be affected. However there are lots of differences:

• BPEL and BPM are QUITE different things so they cannot even be compared. The problems boils down to the fact that these YEARS maybe BPEL has been marketed for something which isn’t: that is a Business Process Management framework.
• BPEL is MADE up for service orchestration, that is publishing new services as a function of other services.
• while BPM si needed for HANDLING human TASK management functionalities and subprocess management.

In my opinion one of the biggest obstacle in the movement towards SOA adoption is the organization own IT department.Too many people in the IT organization conceive SOA as a technology concept only, and as such think of SOA as just a set of technologies and infrastructure for exposing, securing, running, and managing Services.

Put it this way, SOA is nothing more than Web Services and standardized middleware. The critical flaw in thinking is confusing the technology that sits BENEATH the Services level of abstraction and the mechanism by which Services are accessed with the ARCHITECTURAL approach that aims to decouple the implementation from the consumption and focus on SUSTAINABLE architecture that allows for continuous CHANGE.

Successful SOA adoption requires a CULTURAL shift in the way IT is done. The Service-oriented movement to agility and loose coupling demands a shift from traditional, waterfall styles of development (design-build-test-deploy-manage) to iterative approaches to continuous Service modeling

In my opinion one of the biggest obstacle in the movement towards SOA adoption is the organization own IT department.Too many people in the IT organization conceive SOA as a technology concept only, and as such think of SOA as just a set of technologies and infrastructure for exposing, securing, running, and managing Services.

Put it this way, SOA is nothing more than Web Services and standardized middleware. The critical flaw in thinking is confusing the technology that sits beneath the Services level of abstraction and the mechanism by which Services are accessed with the architectural approach that aims to decouple the implementation from the consumption and focus on sustainable architecture that allows for continuous change.

Successful SOA adoption requires a cultural shift in the way IT is done. The Service-oriented movement to agility and loose coupling demands a shift from traditional, waterfall styles of development (design-build-test-deploy-manage) to iterative approaches to continuous Service modeling

SEAM only works on JDK 5.0 and above. It uses ANNOTATIONS and other JDK 5.0 FEATURES.

Seam only works on JDK 5.0 and above. It uses annotations and other JDK 5.0 features.

Seam runs BEAUTIFULLY on other APPLICATION servers – just like everything else the HIBERNATE team does, this is not a JBoss-only thing.

Seam runs beautifully on other application servers – just like everything else the Hibernate team does, this is not a JBoss-only thing.

Built on the standards Java SERVER Faces and EJB 3.0, JBoss Seam unifies component and programming models and delivers a consistent and powerful framework for rapid creation of WEB applications with Java EE 5.0. Seam simplifies web application development and enables new functionality that was difficult to IMPLEMENT by hand before, such as stateful conversations, multi-window operation, and HANDLING concurrent fine-grained AJAX requests. Seam also unifies and integrates popular open source technologies like Facelets, Hibernate, iText, and Lucene.

Built on the standards Java Server Faces and EJB 3.0, JBoss Seam unifies component and programming models and delivers a consistent and powerful framework for rapid creation of web applications with Java EE 5.0. Seam simplifies web application development and enables new functionality that was difficult to implement by hand before, such as stateful conversations, multi-window operation, and handling concurrent fine-grained AJAX requests. Seam also unifies and integrates popular open source technologies like Facelets, Hibernate, iText, and Lucene.

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.

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.

The JGroups framework provides services to ENABLE peer-to-peer communications between NODES in a cluster. It is built on top a stack of network communication protocols that provide transport, DISCOVERY, reliability and failure DETECTION, and cluster membership management services.

The JGroups framework provides services to enable peer-to-peer communications between nodes in a cluster. It is built on top a stack of network communication protocols that provide transport, discovery, reliability and failure detection, and cluster membership management services.

You could activate the “COMMIT Option A” that is the CONTAINER caches entity bean state between transactions. This option assumes that the container has EXCLUSIVE access to the persistent store and therefore it doesnt need to SYNCHRONIZE the in-memory bean state from the persistent store at the beginning of each TRANSACTION.

You could activate the “Commit Option A” that is the container caches entity bean state between transactions. This option assumes that the container has exclusive access to the persistent store and therefore it doesnt need to synchronize the in-memory bean state from the persistent store at the beginning of each transaction.

Basically starting JBOSS with the CONFIGURATION contains everything needed for clustering:

It has all the libraries for clustering:

• JGroups.jar, jboss-cache.jar.
• Clustered BEANS (cluster-service.xml).
• HA-JNDI.
• HTTP session REPLICATIONS (tc5-cluster-service.xml).
• Farming.
• HA-JMS.

Basically starting JBoss with the configuration contains everything needed for clustering:

It has all the libraries for clustering:

A local-tx-datasource identifies a data source that uses transactions, even distributed TRANS actions within the local application SERVER, but doesnt use distributed transactions among MULTIPLE application servers. An xa-datasource on the other hand identifies a data source that uses distributed TRANSACTION among multiple application servers.

A local-tx-datasource identifies a data source that uses transactions, even distributed trans actions within the local application server, but doesnt use distributed transactions among multiple application servers. An xa-datasource on the other hand identifies a data source that uses distributed transaction among multiple application servers.

EJBS are now plain old Java objects (POJO) that expose regular business interfaces (POJI), and there is no requirement for HOME interfaces.

• Use of metadata annotations, an extensible, metadata-driven, attribute-oriented framework that is used to generate Java code or XML deployment descriptors.
• Removal of the requirement for specific interfaces and deployment descriptors (deployment descriptor information can be replaced by annotations).
• Interceptor facility to INVOKE user methods at the invocation of business methods or at life cycle events.
• Default values are used whenever possible.
• Reduction in the requirements for usage of checked exception.
• A complete new persistence model (based on the JPA standard), that supersedes EJB 2.x entity beans

EJBs are now plain old Java objects (POJO) that expose regular business interfaces (POJI), and there is no requirement for home interfaces.

You can’t with a Servlet. A JTA transaction MUST start and FINISH within a single invocation (of the SERVICE() method). You should consider using a Stateful SB. In a SFSB with a JTA transaction, the association between the bean instance and the transaction is retained across multiple client calls.

You can’t with a Servlet. A JTA transaction must start and finish within a single invocation (of the service() method). You should consider using a Stateful SB. In a SFSB with a JTA transaction, the association between the bean instance and the transaction is retained across multiple client calls.

JBOSS registers in the JNDI tree a JTA UserTransaction Object which can be USER to manage a DISTRIBUTED transaction.

JBoss registers in the JNDI tree a JTA UserTransaction Object which can be user to manage a distributed transaction.

YES, that is many threads can access it concurrently and request for sessions. It HOLDS cached data that has been READ in one unit of work and may be reused in a future unit of work. Good PRACTICE is to create it when the APPLICATION is initialized.

Yes, that is many threads can access it concurrently and request for sessions. It holds cached data that has been read in one unit of work and may be reused in a future unit of work. Good practice is to create it when the application is initialized.

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

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

The perception of EJB3 as being a simple clone of Hibernate is PRIMARILY based on developer familiarity with Hibernate and a SIMILARITY of naming, as well as common purpose, and that Hibernate is morphing itself into an EJB3 implementation based on the work going into the specification, not the other way around.

EJBs are supposed to be components, in the sense that they’re not just one CLASS, but a set of classes, descriptors and usage and management contracts. All of this in order to ALLOW a container (JBoss, Weblogic, etc.) to provide services to those components, and to be able to reuse and distribute this components. This services are, among others, transactions, concurrent access control, security, instance pooling, etc.

Hibernate is “just” an ORM (Object/Relational Mapping) tool. Quick and dirty, this means you can store an object tree belonging to an class hierarchy in a relational DB without writing a single SQL query. Quite cool, IMO. But no transaction control, no instance pooling, no concurrency control, and certainly no security.

The perception of EJB3 as being a simple clone of Hibernate is primarily based on developer familiarity with Hibernate and a similarity of naming, as well as common purpose, and that Hibernate is morphing itself into an EJB3 implementation based on the work going into the specification, not the other way around.

EJBs are supposed to be components, in the sense that they’re not just one class, but a set of classes, descriptors and usage and management contracts. All of this in order to allow a container (JBoss, Weblogic, etc.) to provide services to those components, and to be able to reuse and distribute this components. This services are, among others, transactions, concurrent access control, security, instance pooling, etc.

Hibernate is “just” an ORM (Object/Relational Mapping) tool. Quick and dirty, this means you can store an object tree belonging to an class hierarchy in a relational DB without writing a single SQL query. Quite cool, IMO. But no transaction control, no instance pooling, no concurrency control, and certainly no security.

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 application spending all the time. Using Jboss 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.

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 application spending all the time. Using Jboss 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.

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.

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.

JBoss cache is a PRODUCT. Frequently accessed Java objects are cached by utilzing JBoss cache to improve the performance of e-business applications. JBoss decreases the NETWORK traffic and increases the scalability of applications by eliminating UNNECESSARY database access. FULLY transactional features and highly configurable set of options which are to deal with concurrent data access, are provided by JBoss cache in an efficient manner POSSIBLE for the applications.

JBoss cache is a product. Frequently accessed Java objects are cached by utilzing JBoss cache to improve the performance of e-business applications. JBoss decreases the network traffic and increases the scalability of applications by eliminating unnecessary database access. Fully transactional features and highly configurable set of options which are to deal with concurrent data access, are provided by JBoss cache in an efficient manner possible for the applications.