modelant.repository

The repository module provides an interface (API) and an implementation (impl) of a a model repository compliant with Java Metadata Interface (JMI 1.0). The repository implements strictly the JMI 1.0 (JSR-40) specification. The interface (API) module defines how to instantate the repository and create and locate its extents. This API is proprietary, as JMI does not specify it. The JMI repository implementation is Netbeans Meta-Data Repository (MDR). It is possible to use any implementation of the JMI (JSR-40) specification, easily integrated with the API through the standard Java Services framework.

The JMI 1.0 (JSR-40) defines rules to build the interfaces to access a model in a specific modeling language (metamodel), held in a JMI-compliant repository. Therefore the repository module provides also a Maven archetype to generate the Maven project structure, the language-specific interfaces in source, the a pom.xml to compile and publish them as a standalone .jar file.

Compilation Dependencies

The compilation against the model repository needs only the dependency:

<dependencies>
  <dependency>
    <groupId>net.mdatools</groupId>
    <artifactId>modelant.repository.api</artifactId>
    <version>${revision}</version>
  </dependency>
</dependencies>

Execution Dependencies

In order to use the default model repository integrated in modelant out-of-the-box, needed are the following dependencies:

<dependencies>
  <dependency>
    <groupId>net.mdatools</groupId>
    <artifactId>modelant.repository.api</artifactId>
    <version>${revision}</version>
  </dependency>
  <dependency>
    <groupId>net.mdatools</groupId>
    <artifactId>modelant.repository.impl</artifactId>
    <version>${revision}</version>
  </dependency>
</dependencies>

Instantiate a Repository

As of [A4] instantiate the modelant models repostory with the snippet:

import net.mdatools.modelant.repository.api.ModelRepositoryFactory;
...
modelRepository = ModelRepositoryFactory.construct(storage file);

Nevertheless, once the repository is instantiated, it must be closed when done and its resources have to be released. Therefore apply the following idiom of the repository’s lifecycle:

import net.mdatools.modelant.repository.api.ModelRepositoryFactory;
...
  boolean commit;

  modelRepository = ModelRepositoryFactory.construct(storage file);
  try {
    modelRepository.beginTransaction();
    try {
      ..
      manipulate
      ...
      commit = true;
    } catch (Exception ex) { // rollback
      commit = false;
    } finally {
      modelRepository.endTransaction(commit);
    }
  } finally {
    modelRepository.shutdown()
  }

NOTE: Each of the model operations actually establishes its own nested transaction. Also the coordination of the nested transactions takes much more time and resources than handling them separately, therefore in some cases it makes sense to consider the idiom:

import net.mdatools.modelant.repository.api.ModelRepositoryFactory;
...
  modelRepository = ModelRepositoryFactory.construct(storage file);
  try {
    ..
    manipulate (each operation is an individual transaction)
    ...
  } finally {
    modelRepository.shutdown()
  }

Modules