# Com / Fujitsu / Futurity

## Overview

The `com.fujitsu.futurity` package is the root Java package for the **Futurity application platform**, a Java EE–based web application developed by Fujitsu. Futurity is structured around a **regional-variant architecture**, where different market deployments (e.g., Japan, US, Europe) each have their own variant package that customises lifecycle initialisation, request encoding, and deployment configuration while sharing a common application core.

At the package level, Futurity is presently a **skeleton module** — the structure is in place through deployment descriptors and class stubs, but no active runtime logic has been implemented at this layer. The documented sub-modules exist primarily as scaffolding hooks that will be wired together by the servlet container at deployment time.

The platform follows traditional Java EE conventions: the web tier uses `web.xml` (and an environment-specific `web-full.xml`) for component registration, and all entry points into the application flow through standard `javax.servlet` interfaces. No Spring annotations, Java-based configuration, or dependency injection frameworks were detected in the current index.

## Sub-module Guide

The package currently documents one web-tier sub-module:

### web — The Web Entry Boundary

The `com.fujitsu.futurity.web` package is the **entry boundary** for the Futurity application. It sits at the intersection of the servlet container and the application's internal request-processing pipeline, providing two lifecycle hooks (a context listener and a filter) scoped to a single regional variant (`x33`, the Japanese market).

**How the web sub-module works**

The web tier operates in two phases tied to the servlet container lifecycle:

1. **Application startup** — When the servlet container loads the application, it instantiates the registered `ServletContextListener` (`X33AppContextListener`). This is the designated entry point for x33-specific initialisation: loading configuration, setting up shared state, and bootstrapping any resources needed by the application. At present this is a no-op stub.

2. **Request processing** — Every incoming HTTP request passes through the container's filter chain before reaching any servlet or controller. The registered `X33JVRequestEncodingSjisFilter` intercepts here. Its name indicates an original intent to enforce **Shift JIS** (`MS932`) character encoding on request parameters — a standard requirement for legacy Japanese enterprise applications. Currently, the filter passes every request through unmodified.

**Regional-variant structure**

The `x33` package name follows a platform convention where each regional market has its own sub-package. The presence of `x33.filter` and `x33.listener` suggests sibling packages such as `x33us` (US variant) and `x33eu` (European variant) follow the same structure with region-specific encoding (e.g., UTF-8 for US, ISO-8859-1 for legacy EU). This allows each variant to define its own character encoding, localization hooks, and startup behaviour while sharing the broader Futurity application logic.

**How the components relate**

The listener and filter serve complementary roles in the servlet pipeline:

- The **listener** runs once at application startup to set up shared resources and context state.
- The **filter** runs per-request to transform or validate each incoming HTTP request before it reaches application logic.

In a fully implemented variant, the listener would initialise shared state (such as character encoding configuration or regional cache providers), and the filter would enforce that configuration on every request. Together they form the **initialisation and request-processing layer** that sits between the servlet container and the application's business logic.

## Key Patterns and Architecture

### Regional-variant packages

The platform uses a **variant package pattern**: each market deployment gets its own sub-package under `web` with identically named classes but region-specific behaviour. This is a classic multi-tenant strategy in Java EE applications where the deployment descriptor (or Maven profiles) selects which variant package's classes are compiled into the WAR file. The `x33` package is the documented example.

### Servlet lifecycle scaffolding (no-op pattern)

Both the filter and the listener implement standard Java EE interfaces (`javax.servlet.Filter` and `javax.servlet.ServletContextListener`) but contain **no active runtime logic**. This is a consistent architectural signal across the module:

- The skeleton is in place via class declarations and deployment descriptor wiring.
- Actual logic is deferred to sibling packages, global configuration, or future implementation.
- This pattern is common during migration (logic moved to a higher layer), scaffolding (structure built before features), or platform consolidation (shared base with variant-specific overrides).

### Deployment descriptor–driven wiring

All component registration happens through `web.xml` and its full-deployment variant `web-full.xml`. There is no annotation-based registration (e.g., `@WebListener`, `@WebFilter`) or Java configuration class visible. This is consistent with a traditional, XML-driven Java EE approach. The presence of `web-full.xml` suggests deployment-profile overrides for different environments (e.g., production vs. staging, or full vs. lightweight deployment).

### Character encoding by market

The filter naming convention (`X33JVRequestEncodingSjisFilter`) reveals that character encoding is a **first-class concern** scoped per variant. The Japanese variant targets Shift JIS (`MS932`), while other variants would target their market's standard encoding. This per-variant encoding strategy is critical for legacy Japanese enterprise applications where request body parsing must match the encoding of incoming form data.

### Architecture diagram

The following diagram shows how the web-tier components interact through the servlet container lifecycle and request pipeline:

```mermaid
flowchart TD
    subgraph Futurity["com.fujitsu.futurity - Futurity Platform"]
        subgraph Web["com.fujitsu.futurity.web - Web Tier"]
            subgraph X33["x33 - Japanese Market Variant"]
                Listener["X33AppContextListener
(lifecycle bootstrapping)"]
                Filter["X33JVRequestEncodingSjisFilter
(request encoding)"]
            end
        end
    end

    subgraph Deployment["Deployment Layer"]
        WebXML["web.xml / web-full.xml
(deployment descriptors)"]
        Container["Servlet Container
(e.g., Tomcat, WebLogic)"]
    end

    subgraph Request["Runtime Request Flow"]
        Incoming["Incoming HTTP Request"]
        Pipeline["Servlet Filter Chain"]
        Target["Application Servlets
/business logic"]
    end

    WebXML -->|"registers"| Listener
    WebXML -->|"registers and maps"| Filter
    Incoming -->|"enters container"| Pipeline
    Pipeline -->|"passes to"| Target
    Filter -.->|"intercepts each request"| Pipeline
    Listener -.->|"bootstraps container context"| Container
```

## Dependencies and Integration

### External dependencies

- **`javax.servlet`** — The standard Java Servlet API provides all interfaces used by the web tier: `Filter`, `FilterConfig`, `FilterChain`, `ServletRequest`, `ServletResponse`, and `ServletContextListener`. This is the sole dependency detected in the current index.

### Internal dependencies

- **`web.xml`** — Primary deployment descriptor that registers both the `X33AppContextListener` and `X33JVRequestEncodingSjisFilter`.
- **`web-full.xml`** — Full-deployment variant descriptor that includes additional filter mappings, suggesting environment-specific configuration.
- **Sibling regional packages** — Though not yet documented, the `x33` naming convention implies sibling packages (`x33us`, `x33eu`) that mirror this structure with region-specific logic.

### Integration with the broader system

No cross-module relationships were detected in the code index, which is consistent with the module's current stub state. When fully implemented, integration with the broader Futurity platform would occur through:

- **`ServletContext` attributes** — The listener would set shared state (e.g., configuration objects, cache providers) via `ServletContext.setAttribute()`, making them available to all servlets and filters in the application.
- **Shared servlet container configuration** — Global settings in `server.xml` (e.g., `URIEncoding`, connection pool defaults) would complement or supersede per-variant filter logic.
- **Deployment profile selection** — Maven or Ant build profiles would select which regional variant package is compiled into the WAR file at build time.

## Notes for Developers

- **The module is currently skeletal.** Neither the filter nor the listener contains active runtime logic. Before making changes, verify whether encoding or initialisation logic has been migrated to the servlet container configuration (e.g., `server.xml`) or sibling regional packages.

- **The filter is safe to remove or deprecate.** Since `X33JVRequestEncodingSjisFilter.doFilter()` passes requests through unmodified, removing it from `web.xml` has no runtime impact unless filter ordering in the descriptor is significant.

- **To implement the filter**, the standard approach is:

```java
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
        throws IOException, ServletException {
    req.setCharacterEncoding("MS932"); // Shift JIS for Japanese variant
    chain.doFilter(req, res);
}
```

Alternatively, configure the servlet container's `URIEncoding` attribute in `server.xml` for a global approach.

- **The listener should implement `ServletContextListener`** when lifecycle logic is added. The `contextInitialized()` method is the natural place to bootstrap x33-specific resources (configuration loading, cache setup, connection initialisation), and `contextDestroyed()` for cleanup on shutdown.

- **Naming convention.** The `X33` prefix scopes components to the x33 module variant. Adjacent packages likely serve other regional variants (`X33US`, `X33EU`) with their own filter and listener classes, following the same structure documented here.

- **No source files are currently indexed** at the parent package level. This documentation is synthesised from the `web` child module page and the broader platform architecture context.

- **Regional variant strategy.** If adding a new market variant, mirror the `x33` structure: create a sub-package under `web`, implement a character-encoding filter appropriate to the market, and register both the filter and listener in `web.xml`.