The Carbon Java Framework  

The Carbon Component Framework

Carbon FAQ

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Author: Anand Raman (araman at
Version: $Revision: 1.8 $($Author: ghinkl $ / $Date: 2003/05/21 03:42:49 $)
Created: April 2003


What is Carbon?

Carbon is a lightweigth component model for building framework and technical services. The carbon project maintains both a core carbon base and a number of technical services intended to spead up enterprise development.

Why call it Carbon?

The element Carbon plays a important role in the chemistry of life. Carbon has four valence electrons in its outer shell, which can hold a total of eight. This makes carbon equally likely to give up or take on electrons and places it among the most combinable atoms in the universe.

On the same line, the Carbon framework is built around software components which combine with other Carbon components, as well as external components, to create complex systems.

How is Sapient involved with Carbon?

Sapient, a leading business and technology consultancy and has been involved in researching advanced technologies to deliver business value for our clients. Carbon is the result of a number of years of investment in framework technologies. Carbon is open source to benefit our clients and to fill a niche in the development of enterprise software.

Why should I be using Carbon?

Carbon services provide a number of advantages over individual use of underlying technical APIs. The framework creates a centralized system for externalized configuration that creates a more flexible and dynamic application. Carbon services can also be created as lightweight alternatives to the common singleton services that are often created in enterprise applications.

Carbon services are also useful in that they impose the common OO principle of design by interface. By utilizing interfaces and standardized factory construction, carbon allows for the replacement of services through simple system reconfiguration. It also reduces complexity by creating a rigid integration point and standardizing the creation and configuration of those services.

Whats the licensing behind Carbon?

Carbon is released under the Sapient Public License 1.0. This license is a derivative of the OSI approved Mozilla Public License 1.1. This license ensures that carbon will always be freely available under the supplied terms, for both public and commercial use.


How do I get support?

Carbon is an open source project and as such support can often be found on our mailing lists. Carbon Mailing Lists

Which application servers does Carbon run on?

Carbon is designed to use standard and extension Java apis and does not require a J2EE application server to function. In fact it will run in standalone applications or even applets.

Some of the carbon services are designed to be used within application servers, such as the EJB lookup service and the data source connection service. These services rely on standard J2EE APIs and therefore can be used with any J2EE Application Server.

The Weblogic Management Service or Weblogic Security service are other features designed for use specifically with the WebLogic application server.

How I request for a feature?

Submit your feature request with as many possible artificats here.


Is Carbon modular?

Carbon consists of core infrastructure and a set of modular services. The services are seperate subprojects of carbon and can be chosen as needed to add functionality. Additionally, some modules have depenedencies on other modules, such as the cache modules dependence on the scheduler module. These dependencies are documented.


What are dynamic proxies?

A dynamic proxy class is a class that implements a list of interfaces specified at runtime such that a method invocation through one of the interfaces on an instance of the class will be encoded and dispatched to another object through a uniform interface. For more details refer Dynamic Proxy Classes.

Carbon uses dynamic proxies to tie together a set of interfaces with their implementations to provide a single consistent view of the component. Developers code the business logic and Carbon ties together the service interfaces with the business logic to provide a single consistent and instrumented component view.

How is it different from other frameworks

Whats the difference between deployment properties and deployment service

Deployment properties hold information specific to the current deployment of Carbon. They are used by the Carbon bootstrap process. e.g. Deployment properties can be set to factory implementations to be used by the configuration or the component services. For a exhaustive list of all deployment properties refer the deployment properties home page

The DeploymentService on the other hand is designed to help manage differences in configurations between application deployments. This service service allows configurations for all environments and all instances within each environment to be stored separately and chooses the right configuration at runtime for each environment/instance. This allows all configurations to reside under source control and alleviates the error prone task of maintaining manually modified files on each deployment. For more details refer to the deployment service home page

Where does go?

If you are using to specificy your deployment properties, the file should be available from within the classloader that loads carbon.

The deployment properties file does not go into the directory that holds your Carbon configuration XML files. That directory is not meant to be in your classpath as configuration files are not loaded through a classloader.

Why can't I use the deployment service in startup service?

The deployment service is one of the components started by the startup service. The bootstrap process starts the configuration service, component service, and in the end loads all the components configured in the startup service before servicing any requests.


Are there performance numbers for Carbon?


What are the necessary skill sets to use Carbon?

A major portion of Carbon is built on top of J2SE (standard java packages). Few services like (ejb, email, security, management) build on top of standard extensions and J2EE standards. To get started with Carbon you should be comfortable with Java programming. You might want to pick up specific J2EE technologies as and when the need arises.

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