DEPRECATED BY https://github.com/logykk/enet-jni

Java ENet JNI Wrapper

This project provides Java bindings for the ENet reliable UDP networking library through JNI.

Prerequisites

• JDK 8 or higher (java 21 recommended)
• CMake 3.10 or higher (4.0 recommended)
• A C++ compiler (GCC, MSVC, Clang)
• Gradle

Building

1. Clone the repository with submodules:

git clone --recursive https://github.com/theoplegends/java-enet-jni.git

2. Build the project using Gradle:

./gradlew build

This will:

• Generate JNI headers
• Build the native library
• Run the tests

Usage

Add the library to your project dependencies and make sure the native library is in your library path.

Basic example:

import op.legends.enet.ENetLibrary;

public class Example {
    public static void main(String[] args) {
        // Initialize ENet
        if (ENetLibrary.initialize() < 0) {
            System.err.println("Failed to initialize ENet");
            return;
        }

        try {
            // Create a server host
            long serverHost = ENetLibrary.createHost("127.0.0.1", 34567, 32, 2, 0, 0);
            if (serverHost == 0) {
                System.err.println("Failed to create server host");
                return;
            }

            // Create an event handle
            long event = ENetLibrary.createEvent();

            // Service the host
            while (true) {
                if (ENetLibrary.hostService(serverHost, event, 1000) > 0) {
                    switch (ENetLibrary.getEventType(event)) {
                        case ENetLibrary.EVENT_TYPE_CONNECT:
                            System.out.println("A new client connected!");
                            break;
                        case ENetLibrary.EVENT_TYPE_DISCONNECT:
                            System.out.println("A client disconnected!");
                            break;
                        case ENetLibrary.EVENT_TYPE_RECEIVE:
                            byte[] data = ENetLibrary.getEventPacketData(event);
                            System.out.println("Received message: " + new String(data));
                            break;
                    }
                }
            }
        } finally {
            ENetLibrary.deinitialize();
        }
    }
}

Event Types

The library defines the following event types:

• EVENT_TYPE_NONE (0): No event occurred
• EVENT_TYPE_CONNECT (1): A peer has connected
• EVENT_TYPE_DISCONNECT (2): A peer has disconnected
• EVENT_TYPE_RECEIVE (3): A peer has sent data

API Reference

The ENetLibrary class provides the following main methods:

Initialization

• initialize(): Initialize the ENet library
• deinitialize(): Cleanup the ENet library

Host Management

• createHost(String address, int port, int peerCount, int channelLimit, long incomingBandwidth, long outgoingBandwidth): Create a host for sending/receiving data
• hostDestroy(long host): Destroy a host
• hostService(long host, long event, int timeout): Service a host for events

Peer Management

• connect(long host, String address, int port, int channelCount, long data): Connect to a remote host
• peerDisconnect(long peer, long data): Gracefully disconnect from a peer
• peerDisconnectNow(long peer, long data): Force immediate disconnection
• peerReset(long peer): Reset the peer's connection
• peerSend(long peer, int channelID, byte[] data): Send data to a peer

Event Handling

• createEvent(): Create an event handle
• destroyEvent(long event): Destroy an event handle
• getEventType(long event): Get the type of the event
• getEventPeer(long event): Get the peer associated with the event
• getEventChannelID(long event): Get the channel ID for the event
• getEventData(long event): Get the event data
• getEventPacketData(long event): Get the packet data from the event

Packet Management

• createPacket(byte[] data, int flags): Create a packet
• destroyPacket(long packet): Destroy a packet

Statistics and Monitoring

• getPeerState(long peer): Get the current state of a peer
• getPeerRoundTripTime(long peer): Get the current round trip time
• getPeerLastRoundTripTime(long peer): Get the last round trip time
• getPeerLastSendTime(long peer): Get the last send time
• getPeerLastReceiveTime(long peer): Get the last receive time
• getPeerPacketsSent(long peer): Get the number of packets sent
• getPeerPacketsLost(long peer): Get the number of packets lost

Testing

The project includes comprehensive unit tests that demonstrate the functionality of the library. Run the tests using:

./gradlew test

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the SKID License - see the LICENSE file for details.