I2P 文档撰写指南

❌ BAD: "The ClientApp interface probably requires three constructor parameters."
✅ GOOD: "The ClientApp interface requires this constructor signature: 
         public MyClientApp(I2PAppContext context, ClientAppManager manager, String[] args)"

❌ BAD: "Use the port mapper for service discovery."
✅ GOOD: "The port mapper offers a simple directory for internal TCP services. 
         Register loopback ports so other applications can discover your service 
         without hardcoded addresses."

The `startup()` method has signature `void startup() throws IOException` and must 
execute without blocking. The method must call `ClientAppManager.notify()` at least 
once to transition from INITIALIZED state.

### clients.config Properties

**Required:**
- `clientApp.N.main` - Full class name (no default)

**Optional:**
- `clientApp.N.delay` - Seconds before starting (default: 120)
- `clientApp.N.onBoot` - Forces delay=0 if true (default: false, added in 0.9.4)

❌ BAD: "Common registrations include console, i2ptunnel, Jetty, sam, and bob"

✅ GOOD: "Common port mapper service constants from `net.i2p.util.PortMapper`:
- `SVC_CONSOLE` - Router console (default port 7657)
- `SVC_HTTP_PROXY` - HTTP proxy (default port 4444)
- `SVC_SAM` - SAM bridge (default port 7656)"

Note that client registry and port mapper are separate systems:
- **ClientAppManager registry** enables inter-application communication by name lookup
- **PortMapper** maps service names to host:port combinations for service discovery
- **i2ptunnel tunnel types** are configuration values (tunnel.N.type), not service registrations

> **Note:** The I2P network hosts comprehensive documentation at http://idk.i2p/javadoc-i2p/ 
> which requires an I2P router for access. For clearnet access, use the GitHub Pages 
> mirror at https://eyedeekay.github.io/javadoc-i2p/

✅ GOOD: [ClientApp Javadoc](https://i2p.github.io/i2p.i2p/net/i2p/app/ClientApp.html)
✅ GOOD: [Configuration Specification](https://geti2p.net/spec/configuration)

❌ BAD: See the ClientApp docs at http://idk.i2p/...
❌ BAD: [link](url) with no descriptive text

---
title: "Document Title"
description: "Brief description"
slug: "url-slug"
lastUpdated: "2025-10"
accurateFor: "2.10.0"
reviewStatus: "verified"
---

Managed clients were introduced in **version 0.9.4** (December 17, 2012) and 
remain the recommended architecture as of **version 2.10.0** (September 9, 2025). 
The current API version is **0.9.66**.

**Version history:**
- **0.9.4 (December 2012)** - Managed clients introduced
- **0.9.42 (2019)** - clients.config.d/ directory structure added
- **1.7.0 (2021)** - ShellService added for external program tracking
- **2.10.0 (September 2025)** - Current release, no API changes to managed clients

> **Deprecated:** This feature was deprecated in version X.Y.Z and will be removed 
> in version A.B.C. Use [alternative feature](link) instead.

The `net.i2p.app.ClientApp` interface requires implementation of three lifecycle 
methods. When a ClientApp starts, the manager calls `startup()`...

### Example: Registering with Port Mapper

\`\`\`java
// Register HTTP proxy service
context.portMapper().register(
    PortMapper.SVC_HTTP_PROXY, 
    "127.0.0.1", 
    4444
);

// Later, retrieve the port
int port = context.portMapper().getPort(PortMapper.SVC_HTTP_PROXY);
if (port == -1) {
    // Service not registered
}
\`\`\`

### Example: clients.config.d/ Entry

File: `clients.config.d/00-console.config`

\`\`\`properties
# Router console configuration
clientApp.0.main=net.i2p.router.web.RouterConsoleRunner
clientApp.0.name=Router Console
clientApp.0.args=7657 ::1,127.0.0.1 ./webapps/
clientApp.0.delay=0
clientApp.0.onBoot=true
\`\`\`

\`\`\`bash
# Install I2P on Debian/Ubuntu
$ sudo apt-get install i2p

# Start the router
$ i2prouter start
\`\`\`

❌ BAD: "Obviously, you should implement the startup() method."
✅ GOOD: "Managed clients must implement the startup() method to initialize resources."

❌ BAD: "Even a junior dev knows you need to call notify()."
✅ GOOD: "The manager requires at least one notify() call during startup to track state transitions."

❌ PASSIVE: "The ClientAppManager is notified by the client when state changes."
✅ ACTIVE: "The client notifies ClientAppManager when state changes."

✅ "Implement these three lifecycle methods:"
✅ "Call manager.notify() after changing state."
✅ "Register services using context.portMapper().register()"

✅ GOOD: "The netDb (network database) stores information about I2P routers and destinations."
❌ BAD: "Query the netDb for peer info." (no explanation)

# Document Title (h1 - only one per document)

## Major Section (h2)

### Subsection (h3)

#### Detail Section (h4)

**Bold text for emphasis within sections**

> **Note:** Additional information that clarifies the main content.

> **Warning:** Important information about potential issues or breaking changes.

> **Deprecated:** This feature is deprecated and will be removed in version X.Y.Z.

> **Status:** Current implementation status or version information.

- First item
- Second item
- Third item

1. First step
2. Second step
3. Third step

**Term One**
: Explanation of term one

**Term Two**  
: Explanation of term two

✅ "Register with ClientAppManager using manager.register(this) for name-based lookup."
✅ "Register with PortMapper using context.portMapper().register() for port discovery."

❌ "Some applications register services."
✅ "Applications implementing ClientApp may register with ClientAppManager 
   using manager.register(this) to enable name-based lookup."

❌ "Configuration files go in the config directory."
✅ "Modern I2P installations store client configurations in 
   $I2P/clients.config.d/ as individual files."

---
title: "Document Title"
description: "Brief description under 160 characters"
slug: "url-slug"
lastUpdated: "2025-10"
accurateFor: "2.10.0"
reviewStatus: "verified"
---

See [clients.config specification](https://geti2p.net/spec/configuration#clients-config)

For more details, see [ClientApp Javadoc](https://i2p.github.io/i2p.i2p/net/i2p/app/ClientApp.html)

View source: [ClientApp.java](https://i2pgit.org/I2P_Developers/i2p.i2p/src/branch/master/core/java/src/net/i2p/app/ClientApp.java)

| Property | Type | Default | Description |
|----------|------|---------|-------------|
| `main` | String | (required) | Full class name |
| `delay` | Integer | 120 | Seconds before start |
| `onBoot` | Boolean | false | Force immediate start |

\`\`\`java
// Java code
\`\`\`

\`\`\`bash
# Shell commands
\`\`\`

\`\`\`properties
# Configuration files
\`\`\`

\`\`\`xml
<!-- XML files -->
\`\`\`