# Root

## Overview

The `Root` area appears to represent the top-level web application namespace for this codebase. The child documentation shows three distinct integration surfaces under it:

- `com.fujitsu` for container-facing application wiring
- `eo.web` for configuration-driven web page assembly
- `javax.faces` for JSF/servlet integration

Taken together, these modules suggest a system built around web container entry points rather than a single monolithic application core. The root package is not where business rules seem to live; instead, it appears to organize the framework hooks that let the application start, route requests, and expose pages through the servlet container.

## Sub-module Guide

### `com.fujitsu`

The `com.fujitsu` namespace appears to be the vendor or product-level root for the web integration layer. Its child documentation indicates that the real behavior lives under `com.fujitsu.futurity`, where two servlet-oriented responsibilities are separated:

- **Lifecycle integration** through a context listener
- **Request integration** through a filter

This means `com.fujitsu` is best understood as the namespace umbrella, while `com.fujitsu.futurity` contains the actual container hooks. The relationship is structural: the parent groups the code, and the child exposes the runtime extension points.

### `eo.web`

`eo.web` appears to be the application’s web presentation layer. The documented child, `eo.web.webview`, shows a thin adapter pattern where:

- `ACA001SFBean` carries page state
- `ACA001SFLogic` provides the `execute()` entry point

This package seems to bridge XML/JSP configuration and executable page logic. In contrast to `com.fujitsu`, which is centered on servlet container hooks, `eo.web` is centered on page assembly and view execution.

### `javax.faces`

`javax.faces` appears to be the JSF integration namespace. Its child package `javax.faces.webapp` exposes `FacesServlet`, which acts as the handoff point from the servlet container into the Faces runtime.

This module is similar to `com.fujitsu` in that it represents infrastructure wiring, but it is distinct because it anchors the JSF framework boundary rather than application-specific request handling.

### How the sub-modules relate

These sub-modules appear to work at different layers of the same web stack:

- `javax.faces` provides the framework entry point for JSF requests
- `com.fujitsu` provides application lifecycle and request interception hooks
- `eo.web` provides page-level view and execution wiring

The relationship is therefore complementary rather than hierarchical in a business sense. They seem to solve different parts of the web application bootstrap and request flow.

## Key Patterns and Architecture

### Container-driven integration

A strong theme across the child pages is configuration-based wiring. Runtime behavior is attached through deployment descriptors and external XML/JSP configuration rather than through direct bootstrap code.

This appears in several places:

- `web.xml` and `web-full.xml` bind servlet, filter, and listener classes
- XML and JSP resources bind `eo.web.webview` classes into page flow
- `FacesServlet` is activated through descriptor-based servlet configuration

This suggests the codebase depends on the servlet container and JSF runtime to discover and invoke the relevant classes.

### Separation by runtime scope

The available documentation suggests a clean split by execution scope:

- **Application scope** - handled by listeners
- **Request scope** - handled by filters and servlets
- **Page scope** - handled by web-view beans and logic classes

That separation is useful because it keeps lifecycle concerns, request processing, and page behavior from being tangled together.

### Thin adapter layers

Each child module looks intentionally narrow in scope:

- `com.fujitsu.futurity` exposes listener/filter hooks
- `eo.web.webview` exposes page bean and logic classes
- `javax.faces.webapp` exposes the Faces servlet bridge

The common pattern is that these packages adapt the surrounding framework’s expectations rather than implementing deep internal services. This appears to make the root package more about integration than domain orchestration.

### System interaction diagram

```mermaid
flowchart TD
Root["Root"] --> ComFujitsu["com.fujitsu"]
Root --> EoWeb["eo.web"]
Root --> JavaxFaces["javax.faces"]
ComFujitsu --> Futurity["com.fujitsu.futurity"]
EoWeb --> Webview["eo.web.webview"]
JavaxFaces --> Webapp["javax.faces.webapp"]
Futurity --> Listener["X33AppContextListener"]
Futurity --> Filter["X33JVRequestEncodingSjisFilter"]
Webview --> Bean["ACA001SFBean"]
Webview --> Logic["ACA001SFLogic"]
Webapp --> FacesServlet["FacesServlet"]
Listener --> Lifecycle["Application lifecycle"]
Filter --> Chain["FilterChain"]
Logic --> Execute["execute() entry point"]
FacesServlet --> FacesRuntime["Faces runtime"]
```

This diagram shows the root namespace as an umbrella over three integration-oriented areas. Each child module connects to the runtime at a different point in the web application lifecycle.

## Dependencies and Integration

### External dependencies

The evidence points most clearly to Servlet API and JSF integration points. The relevant runtime contracts include:

- `javax.servlet.Filter`
- `javax.servlet.FilterConfig`
- `javax.servlet.ServletRequest`
- `javax.servlet.ServletResponse`
- `javax.servlet.FilterChain`
- `javax.faces.webapp.FacesServlet`

No package dependencies were resolved for the root module itself, so the integration picture is inferred from the child pages rather than from direct source indexing.

### Configuration-driven connections

The modules are connected to the runtime primarily through descriptor and resource wiring:

- `web.xml`
- `web-full.xml`
- `faces-config.xml`
- application-specific XML and JSP files used by `eo.web`

Because those artifacts name classes explicitly, renames or package moves in the child modules likely require coordinated configuration updates.

### Broader system role

The root package appears to support a web application that combines:

- servlet container lifecycle hooks
- request interception and encoding handling
- JSF servlet entry points
- configuration-driven page execution

That combination suggests a legacy or framework-heavy web stack where integration code is spread across several package namespaces rather than concentrated in one service layer.

## Notes for Developers

- Treat `Root` as an integration umbrella, not as a feature module.
- Changes in the child namespaces may require descriptor updates as well as code changes.
- Preserve class names and package paths that are referenced by XML, JSP, or servlet configuration.
- Expect the runtime behavior to be framework-driven; the important contracts are likely listener, filter, servlet, and page-entry signatures.
- If you are looking for core business logic, this area does not appear to be the primary place to find it.

## Summary

`Root` appears to coordinate three separate but related web integration concerns: application/container hooks (`com.fujitsu`), page assembly (`eo.web`), and JSF entry points (`javax.faces`). The sub-modules do not look tightly coupled to one another at the code level; instead, they seem to cooperate through the servlet container and deployment-time configuration. That makes the root area best understood as the structural boundary of the web application rather than its domain core.