HP's acquisition of Bluestone and its Total-e-Business software suite has endowed the company with a first-rate server platform. Total - e-Server - the application server forming the technological keystone of Hewlett-Packard's Middleware solution - enjoyed many key assets thanks to its modular architecture, optimized for maximum availability and scalability.
HP Application Server (HP-AS) is the direct descendent of Total e-Server. It has greatly improved upon the modular architecture of its predecessor, while bringing major improvements and a host of new features. In particular, it is worth highlighting the use of Java Management Extensions (JMX) as the primary mechanism for integration and communication between the different components of the architecture. One new priority is the emphasis on standards compliance, the aim being to offer increasing compatibility with the latest versions of the J2EE standard. HP-AS is therefore fully compatible with the J2EE 1.2 specification and supports the majority of features covered in J2EE 1.3 , and is expected to be announced as J2EE 1.3 certified at the JavaOne show in March, 2002.
Specific features of the Application Server
HP Application Server is available in two versions::
- HP Application Server (HP-AS)
- HP Application Server Resilient Edition, with enhanced, mission-critical functionality
We certainly applaud HP's strategic decision to make HP-AS available free of charge. This version, available on CD or by download, includes a license that authorizes development and production use of applications within an organization. We imagine that this decision will help increase distribution and penetration of the HP solution and will be an important factor in its success. Furthermore, HP-AS Resilient Edition, while not free, adds all of the mission-critical, fault tolerant capabilities and is very aggressively priced. HP-AS is clearly out to claim ownership in the realm of lowest Total Cost of Ownership.
The specific features of HP-AS can be split into three main areas:
- Modularity and extensibility: an extensible, modular service architecture whose different components are integrated into a JMX-based framework.
- Reliability and performance: an architecture designed to favor high availability, load balancing, fault-tolerance, hot deployment and dynamic application launching.
- Versatility: the inclusion of an XML content management framework to facilitate development of multichannel applications.
Not only does HP-AS comply fully with the J2EE 1.2 specification, it also almost completely supports the more recent version of the standard, J2EE 1.3. HP is likely to announce its J2EE 1.3 at the JavaOne show in March, 2002.
The different technologies supported by HP-AS are summarized in the table below:
|Technology||HP-AS 8.0 Standard Edition||HP-AS 8.0 Resilient Edition|
|Database Connectivity||JDBC 2.0||JDBC 2.0, XA|
|Naming & Directory Services||JNDI 1.2.1||JNDI 1.2.1|
|Java Servlets||Servlet 2.3||Servlet 2.3|
|Java Server Pages||JSP 1.2||JSP 1.2|
|Enterprise JavaBeans||EJB 1.1 & EJB 2.0 (*)||EJB 1.1 & EJB 2.0 (*)|
|RMI-IIOP||RMI-IIOP 1.0||RMI-IIOP 1.0|
|Object Request Broker||Iona Orbix2000||Iona Orbix2000|
|Mail services||JavaMail 1.1
|Transaction services||JTA 1.0.1,
Local transaction support
Global transaction support (XA)
|Asynchronous messaging||n/a||JMS 1.0.2
HP Message Service 1.0
SonicMQ 3.5 L.E.
|Enterprise Connector Architecture||JCA 1.0||JCA 1.0|
|XML processing||JAXP 1.1
SAX 2, DOM Level 1 & 2, XSLT,
SAX 2, DOM Level 1 & 2, XSLT,
|Management Extensions||JMX 1.0||JMX 1.0|
|Security & authentication||JAAS 1.0
Fig. 1 - HP-AS J2EE compliance
HP-AS is a 100% Java environment with its own integrated HTTP server. However, HP-AS can also be coupled with the leading Web servers on the market:
- Apache HTTP Server
- Microsoft Internet Information Server
- iPlanet Web Server
HP-AS features a modular, flexible architecture:
- The application server consists of a set of pluggable components or 'services'
- Deployment of each of these services is optional, and configurable. This means you can adapt the server configuration, thereby limiting the resources being used to the bare essentials
This modular architecture also endows HP-AS with good prospects for extensibility. Indeed, to take a new technology on board, you simply need to develop a suitable plug-in that can be deployed as an additional service..
The HP-AS environment also supports hot-versioning: any alterations to the configuration are taken into account on the fly. The same is true for deployment and redeployment of applications.
Core Service Framework (CSF)
The HP-AS architecture is based on a framework called the Core Services Framework (CSF), which meets the specifications covered by the Java Services Framework (JSR-111). The CSF contains the different elements required for deploying services:
- Referencing of services and resources
- Cooperation between entities in the framework
- Setup of the standard interface and environment required by Services
- Management of resource access
Within the framework, by using Partitions you can separate different services (logically or functionally), so as to prevent interference between them. This separation may be necessary, for example, for Application Service Providers (ASPs).
There is only one partition by default, the root partition, which contains the HP-AS server kernel. HP-AS's set of common services also resides in the root partition and cannot be duplicated in other partitions.
Each partition has its own security settings and own CLASSPATH (enabling different versions of services or APIs to co-exist on the same server). Within a single partition, all the services share the same resources.
Using partitions therefore makes it possible to keep different sets of services well isolated. However, it is possible for an incident occurring in one partition to alter the operation of other partitions, if the incident involves one of the common services residing in the root partition.
HP-AS is made up of a collection of different Services which co-operate within the Core Services Framework. These Services include the three main containers required in a J2EE environment:
- the Web container, which hosts the servlets and JSP pages for applications
- the EJB container, which hosts the EJB components of applications
- the Application Client container, released as an early access feature, which includes services for remote client application
The implementations of these container services are compatible with the J2EE specifications (Servlet 2.3, JSP 1.2, and EJB 1.1 and 2.0). Moreover, a large number of APIs are available for these services: JNDI, JDBC, JAXP, JAAS, JavaMail, JAF, JMS, JTA, JTS, JCA, and RMI-IIOP.
Other Services manage interconnection, persistence, transactions, security, access control, and include:
- The Listener - the entry point for requests destined for the application server, which supports the HTTP and HTTPS communication protocols (SOAP support is additional, via the HP Web Service Platform)
- Comprehensive state management, enabling you to choose multiple persistence strategies in line with performance and availability constraints
- The transaction management service Total e-Transaction (based on Arjuna JTS), which enables use of distributed transactions via the XA protocol
- A JAXP service giving simple, standardized access to processing tools (parsing, transformation, reading/writing) for XML documents
- An XML transformation service called XTF (XML Transformation Framework), used, in particular, to adapt content for multiple graphical interfaces (browsers, PDAs, mobile phone, etc.)
- A JMS service coupled with a MOM (Message-Oriented Middleware) HP Message Service 1.0 for processing asynchronous messages between applications
(*) EJB 2.0 support: full support for message-driven beans, CMP entity bean support available as an early access feature (full support for EJB 1.1 BMP and CMP entity beans included).
Copyright 2002 TechMetrix Research. TechMetrix is a technology-oriented analyst firm focused on e-business application development needs. TechMetrix is also backed by its parent company, a European global system integrator - SQLI - with more than 800 developers in the field.
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