Minor Netty cleanup

proxy/src/main/java/com/velocitypowered/proxy/VelocityServer.java

@@ -265,15 +265,11 @@ public class VelocityServer implements ProxyServer {
     logger.info("Loaded {} plugins", pluginManager.getPlugins().size());
   }
 
-  public EventLoopGroup getWorkerGroup() {
+  public Bootstrap createBootstrap() {
-    return this.cm.getWorkerGroup();
-  }
-
-  public Bootstrap initializeGenericBootstrap() {
     return this.cm.createWorker();
   }
 
-  public Bootstrap initializeGenericBootstrap(EventLoopGroup group) {
+  public Bootstrap createBootstrap(EventLoopGroup group) {
     return this.cm.createWorker(group);
   }
 

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/VelocityServerConnection.java

@@ -12,7 +12,6 @@ import static com.velocitypowered.proxy.network.Connections.READ_TIMEOUT;
 
 import com.google.common.base.Preconditions;
 import com.velocitypowered.api.network.ProtocolVersion;
-import com.velocitypowered.api.proxy.ConnectionRequestBuilder;
 import com.velocitypowered.api.proxy.ServerConnection;
 import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
 import com.velocitypowered.api.proxy.server.ServerInfo;
@@ -77,7 +76,7 @@ public class VelocityServerConnection implements MinecraftConnectionAssociation,
     CompletableFuture<Impl> result = new CompletableFuture<>();
     // Note: we use the event loop for the connection the player is on. This reduces context
     // switches.
-    server.initializeGenericBootstrap(proxyPlayer.getMinecraftConnection().eventLoop())
+    server.createBootstrap(proxyPlayer.getMinecraftConnection().eventLoop())
         .handler(new ChannelInitializer<Channel>() {
           @Override
           protected void initChannel(Channel ch) throws Exception {

proxy/src/main/java/com/velocitypowered/proxy/network/ConnectionManager.java

@@ -18,6 +18,7 @@ import java.util.HashMap;
 import java.util.Map;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public final class ConnectionManager {
 
@@ -113,23 +114,23 @@ public final class ConnectionManager {
   }
 
   public Bootstrap createWorker() {
-    return this.createWorker(this.workerGroup);
+    return this.createWorker(null);
   }
 
   /**
    * Creates a TCP {@link Bootstrap} using Velocity's event loops.
    *
-   * @param group the event loop group to use
+   * @param group the event loop group to use. Use {@code null} for the default worker group.
    *
    * @return a new {@link Bootstrap}
    */
-  public Bootstrap createWorker(EventLoopGroup group) {
+  public Bootstrap createWorker(@Nullable EventLoopGroup group) {
     return new Bootstrap()
         .channel(this.transportType.socketChannelClass)
-        .group(group)
         .option(ChannelOption.TCP_NODELAY, true)
         .option(ChannelOption.CONNECT_TIMEOUT_MILLIS,
             this.server.getConfiguration().getConnectTimeout())
+        .group(group == null ? this.workerGroup : group)
         .resolver(this.resolverGroup);
   }
 
@@ -164,10 +165,6 @@ public final class ConnectionManager {
     return bossGroup;
   }
 
-  public EventLoopGroup getWorkerGroup() {
-    return workerGroup;
-  }
-
   public ServerChannelInitializerHolder getServerChannelInitializer() {
     return this.serverChannelInitializer;
   }

proxy/src/main/java/com/velocitypowered/proxy/network/http/NettyHttpClient.java

@@ -9,7 +9,6 @@ import io.netty.channel.ChannelInitializer;
 import io.netty.channel.EventLoop;
 import io.netty.handler.codec.http.DefaultFullHttpRequest;
 import io.netty.handler.codec.http.HttpClientCodec;
-import io.netty.handler.codec.http.HttpContentCompressor;
 import io.netty.handler.codec.http.HttpHeaderNames;
 import io.netty.handler.codec.http.HttpMethod;
 import io.netty.handler.codec.http.HttpRequest;
@@ -22,6 +21,7 @@ import java.net.URL;
 import java.util.concurrent.CompletableFuture;
 import java.util.function.Consumer;
 import javax.net.ssl.SSLEngine;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class NettyHttpClient {
 
@@ -38,7 +38,7 @@ public class NettyHttpClient {
     this.server = server;
   }
 
-  private ChannelFuture establishConnection(URL url, EventLoop loop) {
+  private ChannelFuture establishConnection(URL url, @Nullable EventLoop loop) {
     String host = url.getHost();
     int port = url.getPort();
     boolean ssl = url.getProtocol().equals("https");
@@ -47,7 +47,7 @@ public class NettyHttpClient {
     }
 
     InetSocketAddress address = InetSocketAddress.createUnresolved(host, port);
-    return server.initializeGenericBootstrap(loop)
+    return server.createBootstrap(loop)
         .handler(new ChannelInitializer<Channel>() {
           @Override
           protected void initChannel(Channel ch) throws Exception {
@@ -74,7 +74,7 @@ public class NettyHttpClient {
    * @param loop the event loop to use
    * @return a future representing the response
    */
-  public CompletableFuture<SimpleHttpResponse> get(URL url, EventLoop loop) {
+  public CompletableFuture<SimpleHttpResponse> get(URL url, @Nullable EventLoop loop) {
     CompletableFuture<SimpleHttpResponse> reply = new CompletableFuture<>();
     establishConnection(url, loop)
         .addListener((ChannelFutureListener) future -> {
@@ -109,18 +109,18 @@ public class NettyHttpClient {
    */
   public CompletableFuture<SimpleHttpResponse> post(URL url, ByteBuf body,
       Consumer<HttpRequest> decorator) {
-    return post(url, server.getWorkerGroup().next(), body, decorator);
+    return post(url, null, body, decorator);
   }
 
   /**
    * Attempts an HTTP POST request to the specified URL.
    * @param url the URL to fetch
    * @param loop the event loop to use
-   * @param body the body to post
+   * @param body the body to post - the HTTP client takes ownership of the buffer
    * @param decorator a consumer that can modify the request as required
    * @return a future representing the response
    */
-  public CompletableFuture<SimpleHttpResponse> post(URL url, EventLoop loop, ByteBuf body,
+  public CompletableFuture<SimpleHttpResponse> post(URL url, @Nullable EventLoop loop, ByteBuf body,
       Consumer<HttpRequest> decorator) {
     CompletableFuture<SimpleHttpResponse> reply = new CompletableFuture<>();
     establishConnection(url, loop)

proxy/src/main/java/com/velocitypowered/proxy/server/VelocityRegisteredServer.java

@@ -19,7 +19,6 @@ import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
-import com.velocitypowered.proxy.protocol.StateRegistry;
 import com.velocitypowered.proxy.protocol.netty.MinecraftDecoder;
 import com.velocitypowered.proxy.protocol.netty.MinecraftEncoder;
 import com.velocitypowered.proxy.protocol.netty.MinecraftVarintFrameDecoder;
@@ -63,7 +62,7 @@ public class VelocityRegisteredServer implements RegisteredServer {
       throw new IllegalStateException("No Velocity proxy instance available");
     }
     CompletableFuture<ServerPing> pingFuture = new CompletableFuture<>();
-    server.initializeGenericBootstrap()
+    server.createBootstrap()
         .handler(new ChannelInitializer<Channel>() {
           @Override
           protected void initChannel(Channel ch) throws Exception {