In-Depth Analysis of the `com.aspectran.embed.activity` Package

1. Design Goals and Key Roles

This package provides the Activity implementation that actually executes programmatic calls initiated from the EmbeddedAspectran service. This package plays a very similar role to the daemon-activity package but is adapted to the specific context of an embedded environment.

The design goals of this package are as follows:

• Concretizing the Execution Context of an Embedded Environment: Inherits from the abstract CoreActivity to provide AspectranActivity, which can process requests in an environment embedded within another Java application.
• Standardization of Programmatic Calls: Provides adapters that convert Map-shaped parameters, attributes, and request bodies passed through EmbeddedAspectran’s translate() method into standard request/response forms that the Aspectran core engine can understand.

In conclusion, this package acts as a bridge that converts and connects data and call methods between the simplified facade EmbeddedAspectran and the complex execution engine CoreActivity.

2. Detailed Class Analysis

AspectranActivity (Implementation Class)

The final implementation of Activity for the embedded environment. A new instance is created each time DefaultEmbeddedAspectran’s translate() method is called.

Key Responsibilities:

• Inherits CoreActivity, thus inheriting all of Aspectran’s standard request processing pipeline (advice, action execution, etc.).
• Maintains the request name, method, attribute map, parameter map, and request body passed via the translate() method as internal state.
• Creates and manages request/response/session adapters specific to the embedded environment.

Key Method Analysis:

• adapt(): The core of adaptation for the embedded environment. It is called at the beginning of CoreActivity’s perform() method to convert programmatic calls into standard interfaces.
  • AspectranRequestAdapter: Wraps the attributeMap, parameterMap, and body passed to the translate() method to act as a RequestAdapter. It is functionally slightly more extended than DaemonRequestAdapter in that it can handle body, making it easier to programmatically simulate requests like POST/PUT.
  • AspectranResponseAdapter: Internally wraps an OutputStringWriter or a Writer directly provided during the translate() call to act as a ResponseAdapter. All response results are written to this Writer.
  • DefaultSessionAdapter: If session management is enabled in the parent EmbeddedAspectran service, it creates a session adapter to support state persistence.

Interaction with Other Classes:

• DefaultEmbeddedAspectran: Within its translate() method, it directly creates AspectranActivity, sets parameters, and then calls prepare() and perform() to execute it.
• CoreActivity: AspectranActivity inherits CoreActivity and uses its execution pipeline as is.
• Classes in com.aspectran.embed.adapter package: AspectranRequestAdapter and AspectranResponseAdapter are directly created and used within the adapt() method.

3. Package Summary and Architectural Significance

The com.aspectran.embed.activity package, along with the activity packages for daemon and shell environments, demonstrates how highly reusable Aspectran’s core execution engine, CoreActivity, is designed.

AspectranActivity handles all the heavy lifting of converting actual programmatic calls into Aspectran’s standard execution model, behind the user-friendly facade of EmbeddedAspectran. Thanks to this adapter layer, the CoreActivity execution engine does not need to distinguish whether its execution was triggered by an HTTP request, an internal daemon call, or a method call from another Java application.

This perfect decoupling makes it very easy to embed Aspectran into other applications and use it as a service component to perform specific functions (e.g., template rendering, rule-based logic execution). This is a key architectural design that allows Aspectran to not only be a standalone application framework but also to fully function as a high-functionality embedded library.