Developing and deploying an OSGi Blueprint service using the was OSGi Feature pack

Developing and deploying OSGi Blueprint service using the WebSphere application Server OSGi Feature Pack

Introduction

As we all know, OSGi was originally an abbreviation for the Open Service Gateway Initiative, applied to home networking and mobile embedded devices. Then, thanks to the rapid development and huge user base of Eclipse, which followed the OSGi specification to refactor its plug-in mechanism, OSGi quickly developed into a de facto industrial standard for Java Dynamic modular systems. On the other hand, in enterprise applications, OSGi is becoming the focus of the field and even the future direction, along with the Blueprint Service specification introduced by OSGi R4.2, and the set of enterprise-level standards set by the OSGi Alliance's Enterprise Experts Group, as the most important of the OSGi Alliance IBM also quickly has the support of the enterprise-class OSGi application programming model in its WebSphere application Server V7. This article is intended to introduce the core concepts of OSGi and its development in enterprise-class applications, and demonstrate how to develop, deploy, and run enterprise-class OSG using the WebSphere application Server V7 Feature Pack for OSGi applications I apply.

Related Concepts of OSGi

What OSGi brings us is a standardized, dynamic, elegant component model that changes the Java traditional flat class loading structure, effectively solves the version conflict problem of Java software, paves the way for Java to be modular, and JCP by JSR-291 the OSGi Core Spec R4.1 specification was brought into the Javase family.

OSGi's ISO OSGi alliance was founded in 1999 and now includes more than 100 members, such as Ibm,ericsson,prosyst,makewave,sap,oracle. In addition to the equinox that Eclipse brings, the common open source OSGi framework is knopflerfish and Apache Felix, among other things. OSGi is also becoming more and more widely used in the business world, including Websphere,weblogic,jboss in the Application Server field, BMW's on-board system, Adobe's CS2, and so on.

The system architecture of OSGi, as shown in Figure 1, consists of the following 4 levels:

Module layer

Life cycle Layer

Service Layer

Security layer.

Figure 1. OSGi System Architecture

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