General

Is Across free to use?

Yes. Across Framework as well as all modules built by the same team are published under the Apache 2.0 license. The source code can be found on the Foreach Bitbucket space.

What experience do I need to get started with Across?

You need a good grasp of Java (8) and Spring Framework. Spring MVC experience is strongly advised, and some Spring Boot knowledge might be helpful.

At the very least you should be familiar with Spring’s approach for dependency injection, the ApplicationContext and java-based configuration.

Other commonly used libraries that are useful to know are Hibernate, Spring Data, Liquibase and Thymeleaf.

What are the dependencies of Across?

At its heart, Across only requires Spring Frameworkand Spring Bootfor running applications. However, most of the provided functionality is aimed at web applications, so Spring MVC usually comes into play as well. When playing on the web, default modules setup Thymeleaf for server-side templating.

When using installers (which is a pretty common thing), a minimal RDBMS is required as well and Liquibase will be used for the default schema. All standard Across modules that require a RDBMS are tested on H2, HSQLDB, MySQL, Oracle, and MS SQL.

All third-party libraries used by Across are free, open source and backed by a large community.

Dependency versions

Across Platform Spring Framework Spring Boot
2.1.x 4.3.x 1.5.x
2.0.x 4.3x 1.4.x

Which versions of Java and Spring is Across compatible with?

The latest version of Across Platform (2.1.x) is compatible with Java 8, Spring Framework 4.3.x and Spring Boot 1.5.x.

See the dependency table for an overview of the current dependencies.

What is the difference between Across Framework and Across Platform?

Across Framework is an actual Java library providing all the infrastructure necessary to build Across modules and to run applications based on them.

Across Platform is a set of curated dependencies and Across modules that play well together and help developers assemble applications. It is provided as a bill-of-material POM, extending the Spring IO platform BOM.

Across applications usually use the Across Platform BOM as a basis, to ensure that both third-party libraries as well as common Across modules are compatible.

Can I use Across without the standard modules?

Absolutely. We advise you to use the Across Platform BOM for dependency management, but there is no requirement to actually use any of the standard modules.

Can I use Across for a non-web application?

Yes. The core framework for bootstrapping a module based application does not require a web context. Be aware, however, that most of Across’ features and modules are web dependent, so you will not be able to use those.

I’d like to contribute. Is that possible?

Absolutely! Across is open source and anyone can fork the repositories on Bitbucket. Please read our contributor guidelines if you are serious about making contributions.

If you’d like to contribute by sharing knowledge there’s also several ways to do so:

  • Write blogs, tutorials and quick starts; we will gladly reference them on the Across website.
  • Answer questions of fellow developers on Stack Overflow, or comment on issues in the issue trackers.
  • Contribute to the documentation of the respective modules.

I have a question. How can I get in touch?

The team actively monitors Stack Overflow, so we prefer you post technical questions there using the tag #across.

More general questions or feature requests can be filed in the issue tracker as a Question issue type. The issue tracker is also the tool used for filing bug reports. You can find the issue tracker of a specific module on the module detail page.

There is also a Gitter channel where most of the core developers reside: https://gitter.im/thinking-across.

If you are looking for professional support, please see our support page.

What do you mean with “modular web applications”?

There are many ways to modularize a web application. In our case we’re talking about an application made up of several Across modules. Across modules can be both technical modules (like a module setting up Hibernate or Ehcache) and functional modules (like a module providing a domain model for working with orders).

An application is a combination of different modules put together. Modules can depend on other modules, but only ever in one direction (no cyclic dependencies).

Technical modules as described above are very common in the Java/Spring landscape, Across, however, aims to stimulate the creation of more functional modules. Although Across can be used perfectly well in a microservice landscape, its greatest value possibly lies in helping developers create “modular monoliths”, aka monolithic applications done in a better way.

Some background on the idea of modularizing monoliths:

Can I use Across for microservices?

Yes, you can, but please be aware that Across is actually better suited for developing modular monoliths and does not necessarily bring much added value for small applications often representing a single module.

The Spring Boot and Spring Cloud communities are very active when it comes to microservices and most of their features have not yet been tested in Across based applications. It might involve some more in-depth technical work to get things working correctly. We can offer commercial support for this if required.

In future releases of Across we expect to improve the out-of-the-box integration with Spring Boot and Spring Cloud libraries.

Can I add my own module to your list?

Absolutely.

If you’ve created your own shared Across module and would like to have it listed on the modules page, just let us know.