arankin-irl / lwsl

Light weight socket library for Java

Light Weight Socket Library

LWSL is an open source socket library made in Java using JSON packets.
It is used to create small backend applications such as verification servers, rats or other simple tasks.
Everyone can contribute by making pull requests.
If you have any issues / new features, present them in the issues tab.
For a faster support, feel free to join my discord here.

Usage

Example chat application

You can take a look at the example on this repository (LWSLChatExample).

Server

To create a server using LWSL, take a look at the example below.

socketServer = new SocketServer(25566)
                .setMaxConnections(20) // 0 for infinite
                .addConnectEvent(socket -> System.out.println(String.format("Client connected! (%s)", socket.toString())))
                .addDisconnectEvent(socket -> System.out.println(String.format("Client disconnected! (%s)", socket.toString())))
                .addPacketReceivedEvent((socket, packet) -> System.out.println(String.format("Packet received! (%s)", packet.getObject().toString())))
                .addReadyEvent(socketServ -> System.out.println(String.format("Socket server is ready for connections! (%s)", socketServ.getServerSocket().toString())))
                .addPacketSentEvent(((socketHandler, packet) -> System.out.println(String.format("Packet sent! (%s)", packet.getObject().toString()))));
socketServer.start();

Client

As for the client side, look at the following example.

SocketClient socketclient = new SocketClient("localhost", 25566)
                .addConnectEvent(onConnect -> System.out.println("Connected!"))
                .addDisconnectEvent(onDisconnect -> System.out.println("Disconnected!"))
                .addPacketReceivedEvent(((socket, packet) -> System.out.println(String.format("Received packet %s from %s.", packet.getObject().toString(), socket.getAddress()))))
                .addPacketSentEvent(((socketClient, packet) -> System.out.println(String.format("Sent packet %s to %s.", packet.getObject().toString(), socketClient.getAddress()))));
socketclient.connect();

Packets

Both the SocketClient and SocketServer can send packets by using the #sendPacket(Packet) method.
To make a custom packet, look at the example below.

public class LoginPacket extends Packet {

    public LoginPacket(String username, String password){
        getObject().put("username", username);
        getObject().put("password", password);
    }
}

That's it! To send it to the server, use the following method.

socketClient.sendPacket(new LoginPacket("Baddeveloper", "password123"));

Or for the client server side:

socketHandler.sendPacket(new LoginPacket("Baddeveloper", "password123"));

You can handle these packets by making an "OnPacketReceived" event.

.addPacketReceivedEvent(((socket, packet) -> {
    JSONObject object = packet.getObject();
        
    if(object.getString("username").equals("Baddeveloper") && object.getString("password").equals("password123"))
    	System.out.println("Logged in!");
})

Controller

The controller can be used to kick all clients, kick a specific client, get a client by its IP, send packets to all connected clients, ...
To get the controller's instance, use the following method.

socketServer.getController();

Here are a couple examples of the controller's usage.

final Controller controller = socketServer.getController();
        
controller.kickClient(controller.getClientByIP("127.0.0.1"));
        
controller.sendPacketToAll(new MessagePacket("Shutting down server!"));
controller.kickAll();

SSL/TLS

You can create an encrypted socket connection by passing an SSLContext object to the SocketClient and SocketServer constructors:

SocketServer socketServer = new SocketServer(25566, SSLContext.getDefault());
socketServer.start();

SocketClient socketclient = new SocketClient("localhost", 25566, SSLContext.getDefault())
socketclient.connect();

To create an SSLContext, you can use the SSLContextUtility in conjunction with the SSLContextConfig.

The SSLContextConfig contains several defaults, so for a standard .jks file, you only need to fill in the location (classpath or filesystem) and password.

These defaults can be overwritten for different types of keystore/truststore, such as PKCS11.

Below is an example of using the SSLContextUtility to construct an SSLContext from an SSLContextConfig:

final SSLContextConfig config = SSLContextConfig.builder()
        .keystoreLocation("keystore.jks") // This is on the classpath
        .keystorePassword("changeit")
        .truststoreLocation("/usr/local/truststore.jks") // This is on the filesystem
        .truststorePassword("changeit")
        .build();
final SSLContext sslContext = SSLContextUtility.getInstance().getSslContext(config);

Installation

If your project is using Maven or Gradle, check the tutorials below.

Maven

<repositories>
	<repository>
		<id>jitpack.io</id>
		<url>https://jitpack.io</url>
	</repository>
</repositories>

<dependency>
	<groupId>com.github.StijnSimons</groupId>
	<artifactId>LWSL</artifactId>
	<version>VERSIONHERE</version>
</dependency>

Don't forget to fill in the version where "VERSIONHERE" is present.
Latest version:

Gradle

allprojects {
	repositories {
		...
		maven { url 'https://jitpack.io' }
	}
}

dependencies {
	implementation 'com.github.StijnSimons:LWSL:VERSIONHERE'
}

Don't forget to fill in the version where "VERSIONHERE" is present.
Latest version:

Contributors

• Baddeveloper (Stijn Simons)
• arankin-irl (Alex Rankin)