LPFCP Java

Expose your functions to the network with just one annotation

LikesPro Function Call Protocol (LPFCP) Java lets you expose ordinary Java and Kotlin classes as remote-callable services with a single annotation. LPFCP Java implements the LPFCP protocol — check out the LPFCP protocol specification — and provides both server and client parts instrumentals.

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Features

• 🌐 Annotation-Driven – Turn any Java/Kotlin class object into an HTTP-accessible service by annotating your functions to expose.
• 🚀 Lightweight – Minimal dependencies and overhead; ideal for microservices and serverless deployments.
• 🔌 Java & Kotlin Support – Use LPFCP from either language with the same ease.
• 🛠 Zero-Boilerplate – No manual serialization or wiring; LPFCP takes care of it using reflection.

Read our Wiki

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Getting Started

Installation

Gradle:

dependencies {
    implementation("io.github.likespro:lpfcp-core:1.1.0") // Core features: getProcessor, .processRequest, etc.
    implementation("io.github.likespro:lpfcp-ktor:1.1.0") // Integration with Ktor, for servers: lpfcpServer, Route.lpfcp, etc.
}

Maven:

<!-- Core features: getProcessor, .processRequest, etc. -->
<dependency>
    <groupId>io.github.likespro</groupId>
    <artifactId>lpfcp-core</artifactId>
    <version>1.1.0</version>
</dependency>

<!-- Integration with Ktor, for servers: lpfcpServer, Route.lpfcp, etc. -->
<dependency>
    <groupId>io.github.likespro</groupId>
    <artifactId>lpfcp-ktor</artifactId>
    <version>1.1.0</version>
</dependency>

Usage

1. Define Your Interface (Shared Code)

interface Calculator {
    fun add(a: Int, b: Int): Int
    fun subtract(a: Int, b: Int): Int
}

2. Implement & Annotate (Server Code)

Annotate your implementation class functions with @LPFCP.ExposedFunction:

class CalculatorImpl : Calculator {
    @LPFCP.ExposedFunction
    override fun add(a: Int, b: Int) = a + b

    @LPFCP.ExposedFunction
    override fun subtract(a: Int, b: Int) = a - b
}

3. Start the Server (Server Code)

Use the embedded server helper to expose your service over HTTP:

fun main() {
    val calculator = CalculatorImpl()
    lpfcpServer(processor = calculator, port = 8080)
        .start(wait = true)
}

4. Call from a Client (Client Code)

Obtain a client-side proxy and invoke methods as if they were local:

fun main() {
    val calculator: Calculator = LPFCP.getProcessor<Calculator>(
        "http://localhost:8080/lpfcp"
    )
    println(calculator.add(1, 2))       // -> 3
    println(calculator.subtract(5, 3))  // -> 2
}

Learn more

Examples

Check out the examples/ folder for a working example of the calculator app in Java & Kotlin.

Wiki

Check out https://likespro.gitbook.io/lpfcp-java to view guides to LPFCP Java library.

Documentation

Check out https://likespro.github.io/lpfcp-java/ to view auto generated documentation for the project by Dokka (similar to Javadoc)

License

LPFCP Java is released under the Mozilla Public License Version 2.0.