derjochen / json4j

API project for JSON entity deserialization and serialization and two adapters for external projects. In a current project I need an abstraction layer for JSON entity operations. Since JSR 367 (Java API for JSON Binding (JSON-B)) is still far away, I created this project.

json4j

Abstraction layer project for JSON entity deserialization and serialization and two adapters for external projects.

Motivation

In a current project I need an abstraction layer for JSON entity operations. Since JSR 367 (Java API for JSON Binding (JSON-B)) is still far away, I created this project.

But why?

The project where this is needed itself is a library. So it should be easily reusable and bring no extra baggage.

Say you have a project and use library A for JSON entity operations. Now you add a new dependency to a library for a REST service you want to use - and this library depends on JSON entity library B. You end up with two dependencies who do exactly the same thing. Who needs that?

If the REST library would just depend on an API project you could use an existing adapter implementation for library A or quickly write one yourself. Problem solved.

Usage

Since this project is currently intended for my java-lib-for-wunderlist project, I keep the usage chapter very short. It basicly works like log4j or slf4j. You depend on the facade project (see Maven) and only use the JSONBindingService interface for JSON-entity-conversion.

The field initialization looks like this:

private JSONBindingService jsonBindingService = JSONBindingServiceFactory.create();

During compile time this code is perfectly fine. When running the program a concrete implementation of the JSONBindingService interface is needed. For that you additionally depend on an adapter implementation (e.g. json4j-gson). In your library project you do not want to have a compile dependency to an adapter implementation, but with a test dependency you actually can run and test your code.

If you have multiple adapter projects in your classpath you can select a specific one by setting the Java system property jochor.servicefactory.de.jochor.lib.json4j.StaticJSONBindingBinder to the full qualified name of the service class.

System.setProperty("jochor.servicefactory.de.jochor.lib.json4j.StaticJSONBindingBinder", "de.jochor.lib.json4j.gson.JSONBindingServiceGson");

Normally this is only necessary if you need different implementation during testing and runtime.

Maven

Dependency Tag

Facade project

<dependency>
	<groupId>de.jochor.lib.json</groupId>
	<artifactId>json4j</artifactId>
	<version>0.3.2</version>
</dependency>

Adapter implementation for GSON v2.3.1

<dependency>
	<groupId>de.jochor.lib.json</groupId>
	<artifactId>json4j-gson</artifactId>
	<version>0.3.2</version>
</dependency>

Adapter implementation for Jackson v2.6.1

<dependency>
	<groupId>de.jochor.lib.json</groupId>
	<artifactId>json4j-gson</artifactId>
	<version>0.3.2</version>
</dependency>

Repository Tag

Releases

<repository>
	<id>jochor-public-releases</id>
	<url>http://maven.jochor.de/content/repositories/public-releases/</url>
</repository>

Snapshots

<repository>
	<id>jochor-public-releases</id>
	<url>http://maven.jochor.de/content/repositories/public-snapshots/</url>
</repository>

json4j's Issues

Prepare and release stable version 0.2.1

Make Bugfix Release containing the small optimizations since 0.2.0.

Add jUnit tests

Add tests to check and test the current features and limitations. Try to make it very generic, so that the tests work for every implementation without changing a thing.

Embed the classes from service-factory

Embed the classes from service-factory during the build process in the project jar. Otherwise there might be version conflicts in using applications for the service-factory jar.

Prepare and release stable version 0.1.0

Check feature and code quality for the first release. Document how to use the library (Maven repository and dependency tags). Increment the version - and push.

Create and integrate Jenkins job

Create a Jenkins job for this project. Add a service hook for it to the project settings.

Make implementation selectable

Adapt to changes in the service-factory project. The static binder has to have a method to return the full qualified name of its implementation. This is used to make an implementation selectable by setting a system property.

Prepare and release stable version 0.2.0

Include the fixed Jackson adapter project and release as 0.2.0.

Adapt to changed init process

Adapt to changed init process of the service-builder project. The basis is no longer a classpath scan but one specific class with a static create() method.

Add JaveDoc and small HowTo

Check the existence and quality of the JavaDoc. Extend where needed.
Add a small HowTo, maybe with an example.