# Root

## Overview

The root package of this codebase represents the top-level namespace grouping three distinct areas of the application:

- **`javax.faces`** -- The JavaServer Faces (JSF) framework layer, providing the MVC infrastructure that handles all HTTP requests through the `FacesServlet` front controller.
- **`com.example`** -- A scaffolding namespace for code-quality rule testing and regression scenarios, containing placeholder classes that exist to satisfy compile-time imports.
- **`com.fujitsu`** -- The Futurity application integration layer, providing servlet container lifecycle hooks (filters and listeners) for enterprise-specific concerns such as Shift JIS character encoding for Japanese-language requests.
- **`eo.web`** -- The JSF web presentation layer built on top of the `javax.faces` framework, organizing user-facing pages as managed beans paired with action logic classes in a consistent MVC pattern.

Together, these packages form the web-facing tier of the application. The `javax.faces.webapp.FacesServlet` serves as the single entry point for all JSF requests, delegating to the `eo.web` presentation layer where each screen is implemented as a managed bean and logic class. The `com.fujitsu` package provides container-level hooks (encoding filters, application listeners) that intercept requests before they reach the JSF layer. The `com.example` package is self-contained scaffolding with no functional relationship to the other packages.

A dominant theme across all four parent-level packages is **scaffolding**. Classes exist with correct structure and XML registrations, but functional logic is largely absent -- suggesting the repository is either in an early infrastructure phase or a legacy codebase where functional code was retired without cleanup.

## Sub-module Guide

### javax.faces

The `javax.faces` package is the top-level namespace for the JSF framework within this codebase. As a Java EE component-based web framework, JSF provides a model-view-controller (MVC) architecture with automatic state management, server-side component lifecycle, and data binding to backing beans.

At the `javax.faces` level, no source files are indexed directly -- it acts as a structural namespace that groups related sub-packages. The actual runtime implementation is delegated to child modules, primarily `javax.faces.webapp`.

#### javax.faces.webapp

The `webapp` package is the web-layer entry point for JSF applications. Its central component is the `FacesServlet` class, which implements the front controller pattern -- all JSF requests flow through this single servlet, which enforces a consistent six-phase lifecycle:

1. **Restore View** -- Reconstruct the component tree for the requested page.
2. **Apply Request Values** -- Populate component fields with submitted parameters.
3. **Process Validations** -- Run registered validators.
4. **Update Model Values** -- Sync values into backing beans.
5. **Invoke Application** -- Execute action methods and navigation rules.
6. **Render Response** -- Generate HTML output.

In this codebase, the `FacesServlet` is a minimal stub class declaration. The actual JSF lifecycle implementation is provided by the JSF runtime library (e.g., Mojarra, MyFaces). The servlet is registered in both `web.xml` and `web-full.xml`, confirming the application targets the full Java EE web profile.

#### javax.faces.webapp -- Interactions

Within this package, the `javax.faces` and `javax.faces.webapp` packages work in an unidirectional dependency chain: `javax.faces.webapp` depends on the parent `javax.faces` framework abstractions (Lifecycle, FacesContext, RenderKit, Expression Language). The webapp package translates container-level HTTP operations into the JSF component lifecycle, and nothing in the framework sub-packages depends back on `webapp`.

```mermaid
flowchart LR
    subgraph FW["javax.faces"]
        JF["javax.faces (framework root)"]
        JFC["javax.faces.context"]
        JFL["javax.faces.lifecycle"]
        JFR["javax.faces.render"]
        JFE["javax.faces.el"]
    end
    subgraph APP["javax.faces.webapp"]
        JFW["FacesServlet"]
    end
    JF --> JFC
    JF --> JFL
    JF --> JFR
    JF --> JFE
    JFW --> JF
    JFW --> JFC
    JFW --> JFL
    JFW --> JFR
    JFW --> JFE
```

### com.example

The `com.example` package serves as the root namespace for a small set of example modules. These appear to be scaffolded for code-quality rule testing and regression scenarios rather than production functionality. The package itself contains no source files at its top level; instead, it organizes child sub-packages that each address a specific issue, rule, or test case.

#### com.example.bugca002

The `bugca002` sub-package provides the `KnownClass` type -- a minimal placeholder class with no fields, no meaningful constructor logic, and a no-op `execute()` method. Its sole purpose is to resolve an import statement from a JSP view in another module (`BugCa002Language Before Import.jsp`), ensuring the import compiles at build time.

The naming convention (`bugca002`) is tied to a specific code-quality rule (mapped from `bug-ca-002`), making it easy to locate the code associated with a given rule fix. It operates in isolation with no dependencies on other sub-modules within this package.

### com.fujitsu

The `com.fujitsu` package is an integration layer between a Java servlet container and the internal business logic of the Futurity system. Its responsibilities include managing servlet container lifecycles and shaping incoming HTTP requests -- particularly for Japanese-language requests requiring Shift JIS (SJIS) character encoding.

At present, this package and its sub-modules are in a **scaffolding state**: structural classes and XML deployment descriptors are in place, but the functional logic within them is not yet implemented.

#### com.fujitsu.futurity

The `com.fujitsu.futurity` subpackage is the web-layer entry point for the Futurity application, exposing servlet extension points (filters and listeners) wired up via `web.xml` and `web-full.xml`. Its primary sub-module is:

##### x33

The `x33` sub-package provides web-layer hooks specific to the X33 module of Futurity, containing two components that operate in a temporal lifecycle chain:

- **X33JVRequestEncodingSjisFilter** -- An HTTP request filter intended to enforce Shift JIS character encoding on incoming requests. Currently delegates every request through without transformation.
- **X33AppContextListener** -- A `ServletContextListener` placeholder intended to fire on application startup and shutdown for setting up and tearing down application-global state. The class body is currently empty.

**Relationship:** The `futurity` package provides the overarching web-tier structure, while `x33` specializes within it for X33-specific encoding and lifecycle needs. In a fully implemented system, the listener would configure application-global state at deployment time, and the filter would read that configuration during every incoming request. Currently, no coupling exists between the two components.

```mermaid
flowchart LR
    subgraph FU["com.fujitsu.futurity"]
        subgraph X33["x33 sub-package"]
            EXF["X33JVRequestEncodingSjisFilter"]
            EXL["X33AppContextListener"]
        end
    end
    EXF -->|reads config from| EXL
    EXF -->|delegates to| CH["FilterChain"]
```

### eo.web

The `eo.web` package is the web presentation layer of the application, built on **JavaServer Faces (JSF)**. It provides the MVC-style view components that render user-facing pages and handle user interactions. This package serves as the bridge between the user interface and the application's business logic -- exposing data via EL-accessible properties, capturing user input, and delegating actions to dedicated logic classes.

The layer follows a consistent JSF managed-bean pattern across all sub-modules: a managed bean (view model) paired with an action logic class (controller), wired together through JSF XML configuration descriptors and consumed by JSP view pages.

#### eo.web.webview

The `eo.web.webview` package acts as a container for individual view sub-modules, each corresponding to a specific screen or form in the application. The primary sub-module is:

##### ACA001SF

**ACA001SF** is a minimal JSF view module for the `ACA001`/`ACA001010PJP` screens. It consists of two classes:

- **ACA001SFBean** -- The view model, exposing a single read-only `value` property (String). Registered via multiple XML configuration files and referenced from JSP views through EL expressions such as `#{aCA001SFBean.value}`.
- **ACA001SFLogic** -- The action handler with an `execute()` method serving as the entry point for user-triggered actions. Currently contains an empty body -- a scaffold awaiting implementation.

The module is referenced by four XML configuration files, one JSP view page, and one external reference file. Two copies of `ACA001SFLogic` exist in the codebase (full fixture and XML unresolved-FQN variants), both functionally identical.

#### eo.web.webview -- Request Flow

Every view in `eo.web.webview` follows the same three-tier JSF MVC pattern:

```mermaid
flowchart LR
    USER["User navigates to JSP"] --> JSP["JSP View Page"]
    JSP --> BEAN["Managed Bean<br/>EL-accessible properties"]
    JSP --> LOGIC["Logic Class<br/>execute() entry point"]
    LOGIC --> SVC["Business / Service Layer"]
```

1. **View Layer** -- JSP pages render the UI, pulling data from beans via EL expressions.
2. **Model Layer** -- Plain Java beans act as the view model, exposing data properties as getters (and optionally setters) accessible through EL.
3. **Controller Layer** -- Dedicated logic classes handle user actions with an `execute()` method as the entry point.

### Cross-Package Relationships

The four parent packages are related as follows:

- **`javax.faces`** provides the foundational JSF framework (`FacesServlet`) that all JSF requests pass through. The `eo.web` layer depends on this framework to serve views.
- **`eo.web`** consumes the JSF framework to render the application's user-facing pages. It is the primary production-facing layer among the four packages.
- **`com.fujitsu`** provides servlet container-level hooks (filters, listeners) that sit between the container and the `eo.web` application code, handling encoding and lifecycle concerns.
- **`com.example`** is self-contained scaffolding with no functional dependencies on the other packages.

```mermaid
flowchart LR
    subgraph Framework["javax.faces"]
        JF["javax.faces (framework root)"]
        JFW["FacesServlet"]
    end
    subgraph App["Application Code"]
        FU["com.fujitsu<br/>Futurity hooks"]
        EO["eo.web<br/>JSF presentation"]
        EX["com.example<br/>Scaffolding"]
    end
    JFW --> EO
    FU --> EO
    EX -.->|independent| JFW
    classDef framework fill:#e1f5fe,stroke:#01579b
    classDef app fill:#f3e5f5,stroke:#4a148c
    class JF,JFW framework
    class FU,EO,EX app
```

## Key Patterns and Architecture

### Front Controller with Stub Implementation

The `FacesServlet` is a canonical front controller. In this codebase, it exists as an empty class declaration -- a placeholder that will be populated by the JSF runtime library. This is consistent with the overall scaffolding pattern in this repository.

### JSF Managed Bean MVC Pattern

Both the `javax.faces.webapp` framework and the application's `eo.web` layer adhere to the JSF managed-bean MVC pattern. Every view consists of three layers:
- **View Layer** -- JSP pages rendering the UI, pulling data from beans via EL expressions.
- **Model Layer** -- Plain Java beans exposing data properties as getters/setters, accessible through EL.
- **Controller Layer** -- Dedicated logic classes with an `execute()` method as the entry point for user actions.

This uniform structure allows each view to evolve independently while maintaining a predictable mental model for developers.

### Scaffolding Across Layers

A dominant theme across all packages is **scaffolding**. Classes exist with correct structure and XML registrations, but functional logic is largely absent:

- `javax.faces.webapp` -- `FacesServlet` is an empty class declaration; lifecycle logic is delegated to the runtime library.
- `com.example` -- Placeholder classes like `KnownClass` exist solely to satisfy import resolution with no-op methods.
- `com.fujitsu` -- Filter and listener stubs are registered in `web.xml` but have no implementation.
- `eo.web` -- Managed beans and logic classes are scaffolds with empty `execute()` methods and minimal properties.

This suggests the repository is either a project in early infrastructure phase, or a legacy codebase where functional code was removed without cleanup.

### Six-Phase Lifecycle Delegation

The `FacesServlet` delegates to a `Lifecycle` abstraction that enforces the six-phase request processing model. This decoupling allows the servlet to remain a thin adapter layer while the lifecycle implementation can be swapped at runtime through the JSF factory mechanism.

### Container-Managed Lifecycle Pattern

Both components in `com.fujitsu.futurity.web.x33` follow the Java EE servlet lifecycle pattern. Neither component manages its own instantiation -- the servlet container creates instances and invokes lifecycle methods based on XML registration. This is the classic "convention over configuration" approach used by `web.xml`-based Java web applications.

### Placeholder / Stub Pattern

In `com.example.bugca002`, the `KnownClass` class is a minimal stub -- no state, no behavior -- that exists solely to satisfy a compile-time import. This is a common technique in Java/JSP projects where a view references a class that may be developed in parallel or exists only for resolution purposes.

### Issue-Tied Packaging

Sub-package names like `bugca002` are tied to specific issue tracker items or code-quality rules, making it easy to locate the code associated with a given fix. This convention suggests the project uses a naming scheme where `bug-ca-NNN` maps to a rule or defect number.

## Dependencies and Integration

### Framework Dependencies

| Dependency | Role |
|---|---|
| `javax.servlet.*` | Servlet API used by `FacesServlet` and filter/listener stubs |
| `javax.faces.*` | JSF framework providing lifecycle, context, component tree, and rendering |
| `javax.faces.context` | `FacesContext` per-request management |
| `javax.faces.lifecycle` | `Lifecycle` and `PhaseListener` abstractions |
| `javax.faces.component` | Server-side component hierarchy |
| `javax.faces.render` | `RenderKit` and component rendering |
| `javax.faces.el` | Expression language and data binding |

### Deployment Integration

| File | Purpose |
|------|---------|
| `web.xml` | Declares `FacesServlet`, listeners (`X33AppContextListener`), and filters (`X33JVRequestEncodingSjisFilter`) |
| `web-full.xml` | Full web profile variant confirming full Java EE profile targeting; mirrors filter registration |
| `faces-config.xml` | JSF managed bean declarations for `eo.web` views |
| Module-specific XMLs | Bean registrations for specific views (e.g., `WEBGAMEN_FULL_ACA001.xml`, `x33S_ACA001.xml`) |

### Cross-Package Relationships

- `javax.faces.webapp` provides the JSF framework foundation (`FacesServlet`) that `eo.web` depends on for serving all JSF requests.
- `eo.web` is the application's JSF presentation layer that consumes the framework to render views.
- `com.fujitsu` provides integration hooks (filter, listener) that operate at the servlet container level, sitting between the container and the `eo.web` application code.
- `com.example` is self-contained scaffolding with no dependencies on the other packages.

```mermaid
flowchart LR
    JFW["FacesServlet"] --> EO["eo.web presentation"]
    FU["com.fujitsu hooks"] --> EO
    EX["com.example"] -.->|independent| JFW
    classDef framework fill:#e1f5fe,stroke:#01579b
    classDef app fill:#f3e5f5,stroke:#4a148c
    class JFW framework
    class FU,EO,EX app
```

### Internal Dependencies

- No internal Futurity classes are imported or referenced from any component in the `com.fujitsu` hierarchy. The components are wired exclusively through XML configuration.
- No outgoing imports have been detected from `eo.web` source files, suggesting sub-modules depend on external logic only through JSF dependency injection or lookup mechanisms.
- No external library dependencies are declared by `com.example` child modules.

## Notes for Developers

### This is largely scaffolding

Across all packages, the codebase exhibits a strong scaffolding pattern. Classes exist with correct structure and XML registrations, but functional logic is largely absent. Before implementing any feature, verify what is actually wired up versus what is placeholder.

### JSF Configuration is Critical

Managed beans in `eo.web` are wired through XML descriptors (`faces-config.xml` and module-specific XMLs). If a managed bean is not declared in the appropriate descriptor, EL expressions will not resolve and the view will fail.

### Bean Property Patterns

- **Read-only properties**: A getter without a setter -- views display data but cannot write it back via EL.
- **Read-write properties**: Both getter and setter present -- enables form data binding where user input flows back into the bean.
- If a managed bean exposes only a getter without a setter, adding a setter is the standard fix if form data binding is required.

### Thread Safety and Singleton Models

- The `FacesServlet` is a singleton -- one instance per web application. Per-request state lives in `ThreadLocal`-backed `FacesContext`.
- Servlet container-managed components (filters, listeners) are also singletons. Any state added to them must be thread-safe.

### Character Encoding Considerations

The `com.fujitsu.futurity.web.x33` package contains a filter intended to enforce Shift JIS character encoding on incoming Japanese-language requests. Before implementing this filter, confirm whether Shift JIS is still a requirement -- modern applications typically use UTF-8.

### Deployment Risks

1. **Listener visibility** -- `X33AppContextListener` in `com.fujitsu` is package-private but needs to be `public` for the servlet container to instantiate it via `web.xml`. A deployment-time `ClassNotFoundException` is a risk.
2. **XML consistency** -- The filter is declared in both `web.xml` and `web-full.xml`. If the server loads one but not the other, behavior may differ.
3. **Servlet registration** -- Without a `<servlet>` declaration and `<servlet-mapping>` in `web.xml`, no JSF requests will be processed -- this is the most common misconfiguration.
4. **Shared state** -- If the listener is implemented to set up application-global configuration, the filter may need to read that configuration. This creates a coupling between the two components that does not currently exist.

### Extension Points

- **Adding a new view**: Create a bean class, a logic class, register the bean in the appropriate XML descriptor, and create the JSP page. Wire them through EL. The logic class's `execute()` method is the designated entry point for action logic.
- **Populating stubs**: Implement the `execute()` method in logic classes and add properties to managed beans as needed. The scaffolding structure makes it safe to evolve stubs without breaking callers.
- **Character encoding**: If Shift JIS support is needed, implement the filter's `doFilter` method with `req.setCharacterEncoding("SJIS")` before the chain delegation.
- **New code-quality rules**: Follow the existing convention -- create a `bug-ca-NNN` directory with a sub-package (e.g., `com.example.bugcaXXX`) and a `KnownClass`-style stub.

### Multiple Source Copies

Some logic classes may exist in multiple locations (e.g., full fixture vs. XML unresolved-FQN variants). Check your build configuration to ensure you are editing the correct variant.

### No Direct Source at Parent Levels

The parent-level packages (`javax.faces`, `com.example`) have no indexed source files at their top level. All concrete implementations live within sub-packages. Focus exploration on individual sub-module wiki pages for specific components.