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cdi

CDI Module​

Gestalt provides a CDI (Contexts and Dependency Injection) module that integrates with CDI containers to enable dependency injection of configuration values.

To use the CDI module, add gestalt-cdi to your build configuration.

The module supports:

  • CDI producer for Gestalt instances
  • Injection of configuration values using @InjectConfig
  • Injection of configuration collections using @InjectConfigs
  • CDI extension for automatic configuration setup

Setting up CDI Integration​

The CDI module provides a GestaltConfigExtension that automatically registers producers for configuration injection.

Injecting Configuration Values​

Use the @InjectConfig annotation to inject individual configuration values:

@Inject
@InjectConfig("db.host")
private String dbHost;

@Inject
@InjectConfig("db.port")
private int dbPort;

Injecting Configuration Collections​

Use the @InjectConfigs annotation to inject collections of configuration:

@Inject
@InjectConfigs("servers")
private List<ServerConfig> servers;

Providing a Custom Gestalt Instance​

You can provide a custom Gestalt instance using a producer:

@Produces
public Gestalt createGestalt() {
    return new GestaltBuilder()
        .addSource(ClassPathConfigSourceBuilder.builder().setResource("/config.properties").build())
        .build();
}

The CDI extension will automatically detect and use the produced Gestalt instance for injections. If no producer is provided, it will create a default instance.

Configuration Classes with Prefix​

You can also create configuration classes that automatically map to a prefix:

@ConfigClassWithPrefix("database")
public class DatabaseConfig {
    @InjectConfig
    private String host;
    
    @InjectConfig
    private int port;
    
    // getters and setters
}