Minor optimizations in pipeline filling

api/src/main/java/us/myles/ViaVersion/api/data/UserConnection.java

@@ -456,7 +456,8 @@ public class UserConnection {
     }
 
     /**
-     * Returns whether this is a client-side connection (a mod integrated into the client itself).
+     * Returns whether this is a client-side connection.
+     * This is a mod integrated into the client itself, or for example a backend Velocity connection.
      *
      * @return whether this is a client-side connection
      */

api/src/main/java/us/myles/ViaVersion/api/protocol/Protocol.java

@@ -496,6 +496,15 @@ public abstract class Protocol<C1 extends ClientboundPacketType, C2 extends Clie
         return null; // Let the protocols hold the mappings to still have easy, static singleton access there
     }
 
+    /**
+     * Returns whether this protocol is a base protocol.
+     *
+     * @return whether this represents a base protocol
+     */
+    public boolean isBaseProtocol() {
+        return false;
+    }
+
     @Override
     public String toString() {
         return "Protocol:" + getClass().getSimpleName();

api/src/main/java/us/myles/ViaVersion/api/protocol/ProtocolManager.java

@@ -46,10 +46,28 @@ public interface ProtocolManager {
      */
     @Nullable Protocol getProtocol(Class<? extends Protocol> protocolClass);
 
+    /**
+     * Returns the base protocol handling incoming handshake packets.
+     *
+     * @return base protocol
+     */
     Protocol getBaseProtocol();
 
+    /**
+     * Returns the base protocol for a specific server protocol version.
+     * The standard base protocols deal with status and login packets for userconnection initialization.
+     *
+     * @return base protocol for the given server protocol version
+     */
     Protocol getBaseProtocol(int serverVersion);
 
+    /**
+     * Returns whether the given protocol is a base protocol.
+     *
+     * @param protocol protocol
+     * @return whether the protocol is a base protocol
+     * @see Protocol#isBaseProtocol()
+     */
     boolean isBaseProtocol(Protocol protocol);
 
     /**
@@ -76,6 +94,7 @@ public interface ProtocolManager {
      *
      * @param baseProtocol       base protocol to register
      * @param supportedProtocols versions supported by the base protocol
+     * @throws IllegalArgumentException if the protocol is not a base protocol as given by {@link Protocol#isBaseProtocol()}
      */
     void registerBaseProtocol(Protocol baseProtocol, Range<Integer> supportedProtocols);
 

api/src/main/java/us/myles/ViaVersion/api/protocol/ProtocolPipeline.java

@@ -22,6 +22,7 @@
  */
 package us.myles.ViaVersion.api.protocol;
 
+import com.google.common.base.Preconditions;
 import us.myles.ViaVersion.api.PacketWrapper;
 import us.myles.ViaVersion.api.Via;
 import us.myles.ViaVersion.api.data.UserConnection;
@@ -36,6 +37,9 @@ import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.logging.Level;
 
 public class ProtocolPipeline extends SimpleProtocol {
+    /**
+     * Protocol list ordered from client to server transforation with the base protocols at the end.
+     */
     private List<Protocol> protocolList;
     private UserConnection userConnection;
 
@@ -66,26 +70,55 @@ public class ProtocolPipeline extends SimpleProtocol {
     }
 
     /**
-     * Add a protocol to the current pipeline
+     * Adds a protocol to the current pipeline.
      * This will call the {@link Protocol#init(UserConnection)} method.
      *
-     * @param protocol The protocol to add to the end
+     * @param protocol protocol to add to the end
      */
     public void add(Protocol protocol) {
-        if (protocolList != null) {
+        Preconditions.checkNotNull(protocolList, "Tried to add protocol too early");
+
         protocolList.add(protocol);
         protocol.init(userConnection);
+
+        if (!protocol.isBaseProtocol()) {
+            moveBaseProtocolsToTail();
+        }
+    }
+
+    /**
+     * Adds a list of protocols to the current pipeline.
+     * This will call the {@link Protocol#init(UserConnection)} method.
+     *
+     * @param protocols protocols to add to the end
+     */
+    public void add(List<Protocol> protocols) {
+        Preconditions.checkNotNull(protocolList, "Tried to add protocol too early");
+
+        protocolList.addAll(protocols);
+        for (Protocol protocol : protocols) {
+            protocol.init(userConnection);
+        }
+
+        moveBaseProtocolsToTail();
+    }
+
+    private void moveBaseProtocolsToTail() {
         // Move base Protocols to the end, so the login packets can be modified by other protocols
-            List<Protocol> toMove = new ArrayList<>();
-            for (Protocol p : protocolList) {
-                if (Via.getManager().getProtocolManager().isBaseProtocol(p)) {
-                    toMove.add(p);
+        List<Protocol> baseProtocols = null;
+        for (Protocol protocol : protocolList) {
+            if (protocol.isBaseProtocol()) {
+                if (baseProtocols == null) {
+                    baseProtocols = new ArrayList<>();
+                }
+
+                baseProtocols.add(protocol);
             }
         }
-            protocolList.removeAll(toMove);
-            protocolList.addAll(toMove);
-        } else {
-            throw new NullPointerException("Tried to add protocol too early");
+
+        if (baseProtocols != null) {
+            protocolList.removeAll(baseProtocols);
+            protocolList.addAll(baseProtocols);
         }
     }
 

bungee/src/main/java/us/myles/ViaVersion/bungee/handlers/BungeeServerHandler.java

@@ -47,6 +47,7 @@ import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
@@ -175,17 +176,19 @@ public class BungeeServerHandler implements Listener {
                     int previousServerProtocol = info.getServerProtocolVersion();
 
                     // Refresh the pipes
-                    List<ProtocolPathEntry> protocols = Via.getManager().getProtocolManager().getProtocolPath(info.getProtocolVersion(), protocolId);
+                    List<ProtocolPathEntry> protocolPath = Via.getManager().getProtocolManager().getProtocolPath(info.getProtocolVersion(), protocolId);
                     ProtocolPipeline pipeline = user.getProtocolInfo().getPipeline();
                     user.clearStoredObjects();
                     pipeline.cleanPipes();
-                    if (protocols == null) {
+                    if (protocolPath == null) {
                         // TODO Check Bungee Supported Protocols? *shrugs*
                         protocolId = info.getProtocolVersion();
                     } else {
-                        for (ProtocolPathEntry prot : protocols) {
-                            pipeline.add(prot.getProtocol());
+                        List<Protocol> protocols = new ArrayList<>(protocolPath.size());
+                        for (ProtocolPathEntry entry : protocolPath) {
+                            protocols.add(entry.getProtocol());
                         }
+                        pipeline.add(protocols);
                     }
 
                     info.setServerProtocolVersion(protocolId);
@@ -230,7 +233,7 @@ public class BungeeServerHandler implements Listener {
                     user.put(info);
                     user.put(storage);
 
-                    user.setActive(protocols != null);
+                    user.setActive(protocolPath != null);
 
                     // Init all protocols TODO check if this can get moved up to the previous for loop, and doesn't require the pipeline to already exist.
                     for (Protocol protocol : pipeline.pipes()) {

common/src/main/java/us/myles/ViaVersion/api/protocol/ProtocolManagerImpl.java

@@ -80,7 +80,7 @@ import java.util.concurrent.locks.ReentrantReadWriteLock;
 import java.util.function.Function;
 
 public class ProtocolManagerImpl implements ProtocolManager {
-    public static final Protocol BASE_PROTOCOL = new BaseProtocol();
+    private static final Protocol BASE_PROTOCOL = new BaseProtocol();
 
     // Input Version -> Output Version & Protocol (Allows fast lookup)
     private final Int2ObjectMap<Int2ObjectMap<Protocol>> registryMap = new Int2ObjectOpenHashMap<>(32);
@@ -187,6 +187,7 @@ public class ProtocolManagerImpl implements ProtocolManager {
 
     @Override
     public void registerBaseProtocol(Protocol baseProtocol, Range<Integer> supportedProtocols) {
+        Preconditions.checkArgument(baseProtocol.isBaseProtocol(), "Protocol is not a base protocol");
         baseProtocols.add(new Pair<>(supportedProtocols, baseProtocol));
         if (Via.getPlatform().isPluginEnabled()) {
             baseProtocol.register(Via.getManager().getProviders());
@@ -297,12 +298,7 @@ public class ProtocolManagerImpl implements ProtocolManager {
 
     @Override
     public boolean isBaseProtocol(Protocol protocol) {
-        for (Pair<Range<Integer>, Protocol> p : baseProtocols) {
-            if (p.getValue() == protocol) {
-                return true;
-            }
-        }
-        return false;
+        return protocol.isBaseProtocol();
     }
 
     @Override

common/src/main/java/us/myles/ViaVersion/protocols/base/BaseProtocol.java

@@ -21,6 +21,7 @@ import us.myles.ViaVersion.api.PacketWrapper;
 import us.myles.ViaVersion.api.Via;
 import us.myles.ViaVersion.api.data.UserConnection;
 import us.myles.ViaVersion.api.platform.providers.ViaProviders;
+import us.myles.ViaVersion.api.protocol.Protocol;
 import us.myles.ViaVersion.api.protocol.ProtocolPathEntry;
 import us.myles.ViaVersion.api.protocol.ProtocolPipeline;
 import us.myles.ViaVersion.api.protocol.ProtocolVersion;
@@ -30,6 +31,7 @@ import us.myles.ViaVersion.api.type.Type;
 import us.myles.ViaVersion.packets.Direction;
 import us.myles.ViaVersion.packets.State;
 
+import java.util.ArrayList;
 import java.util.List;
 
 public class BaseProtocol extends SimpleProtocol {
@@ -59,21 +61,26 @@ public class BaseProtocol extends SimpleProtocol {
                     // Choose the pipe
                     int serverProtocol = Via.getManager().getProviders().get(VersionProvider.class).getClosestServerProtocol(wrapper.user());
                     info.setServerProtocolVersion(serverProtocol);
-                    List<ProtocolPathEntry> protocols = null;
+                    List<ProtocolPathEntry> protocolPath = null;
 
-                    // Only allow newer clients or (1.9.2 on 1.9.4 server if the server supports it)
+                    // Only allow newer clients (or 1.9.2 on 1.9.4 server if the server supports it)
                     if (info.getProtocolVersion() >= serverProtocol || Via.getPlatform().isOldClientsAllowed()) {
-                        protocols = Via.getManager().getProtocolManager().getProtocolPath(info.getProtocolVersion(), serverProtocol);
+                        protocolPath = Via.getManager().getProtocolManager().getProtocolPath(info.getProtocolVersion(), serverProtocol);
                     }
 
                     ProtocolPipeline pipeline = wrapper.user().getProtocolInfo().getPipeline();
-                    if (protocols != null) {
-                        for (ProtocolPathEntry prot : protocols) {
-                            pipeline.add(prot.getProtocol());
+                    if (protocolPath != null) {
+                        List<Protocol> protocols = new ArrayList<>(protocolPath.size());
+                        for (ProtocolPathEntry entry : protocolPath) {
+                            protocols.add(entry.getProtocol());
+
                             // Ensure mapping data has already been loaded
-                            Via.getManager().getProtocolManager().completeMappingDataLoading(prot.getProtocol().getClass());
+                            Via.getManager().getProtocolManager().completeMappingDataLoading(entry.getProtocol().getClass());
                         }
 
+                        // Add protocols to pipeline
+                        pipeline.add(protocols);
+
                         // Set the original snapshot version if present
                         ProtocolVersion protocol = ProtocolVersion.getProtocol(serverProtocol);
                         wrapper.set(Type.VAR_INT, 0, protocol.getOriginalVersion());
@@ -94,6 +101,11 @@ public class BaseProtocol extends SimpleProtocol {
         });
     }
 
+    @Override
+    public boolean isBaseProtocol() {
+        return true;
+    }
+
     @Override
     public void init(UserConnection userConnection) {
         // Nothing gets added, ProtocolPipeline handles ProtocolInfo

common/src/main/java/us/myles/ViaVersion/protocols/base/BaseProtocol1_7.java

@@ -199,6 +199,11 @@ public class BaseProtocol1_7 extends SimpleProtocol {
         registerIncoming(State.LOGIN, 0x02, 0x02); // Plugin Response (1.13)
     }
 
+    @Override
+    public boolean isBaseProtocol() {
+        return true;
+    }
+
     public static String addDashes(String trimmedUUID) {
         StringBuilder idBuff = new StringBuilder(trimmedUUID);
         idBuff.insert(20, '-');