Replace reflection usage with a supplier

src/main/java/com/github/steveice10/packetlib/AbstractServer.java

@@ -3,23 +3,23 @@ package com.github.steveice10.packetlib;
 import com.github.steveice10.packetlib.event.server.*;
 import com.github.steveice10.packetlib.packet.PacketProtocol;
 
-import java.lang.reflect.Constructor;
 import java.util.*;
+import java.util.function.Supplier;
 
 public abstract class AbstractServer implements Server {
     private final String host;
     private final int port;
-    private final Class<? extends PacketProtocol> protocol;
+    private final Supplier<? extends PacketProtocol> protocolSupplier;
 
     private final List<Session> sessions = new ArrayList<>();
 
     private final Map<String, Object> flags = new HashMap<>();
     private final List<ServerListener> listeners = new ArrayList<>();
 
-    public AbstractServer(String host, int port, Class<? extends PacketProtocol> protocol) {
+    public AbstractServer(String host, int port, Supplier<? extends PacketProtocol> protocolSupplier) {
         this.host = host;
         this.port = port;
-        this.protocol = protocol;
+        this.protocolSupplier = protocolSupplier;
     }
 
     @Override
@@ -33,23 +33,12 @@ public abstract class AbstractServer implements Server {
     }
 
     @Override
-    public Class<? extends PacketProtocol> getPacketProtocol() {
-        return this.protocol;
+    public Supplier<? extends PacketProtocol> getPacketProtocol() {
+        return this.protocolSupplier;
     }
 
     protected PacketProtocol createPacketProtocol() {
-        try {
-            Constructor<? extends PacketProtocol> constructor = this.protocol.getDeclaredConstructor();
-            if(!constructor.isAccessible()) {
-                constructor.setAccessible(true);
-            }
-
-            return constructor.newInstance();
-        } catch(NoSuchMethodError e) {
-            throw new IllegalStateException("PacketProtocol \"" + this.protocol.getName() + "\" does not have a no-params constructor for instantiation.");
-        } catch(Exception e) {
-            throw new IllegalStateException("Failed to instantiate PacketProtocol " + this.protocol.getName() + ".", e);
-        }
+        return this.protocolSupplier.get();
     }
 
     @Override

src/main/java/com/github/steveice10/packetlib/Server.java

@@ -5,6 +5,7 @@ import com.github.steveice10.packetlib.packet.PacketProtocol;
 
 import java.util.List;
 import java.util.Map;
+import java.util.function.Supplier;
 
 /**
  * Listens for new sessions to connect.
@@ -15,35 +16,35 @@ public interface Server {
      *
      * @return The listening host.
      */
-    public String getHost();
+    String getHost();
 
     /**
      * Gets the port the session is listening on.
      *
      * @return The listening port.
      */
-    public int getPort();
+    int getPort();
 
     /**
      * Gets the packet protocol of the server.
      *
      * @return The server's packet protocol.
      */
-    public Class<? extends PacketProtocol> getPacketProtocol();
+    Supplier<? extends PacketProtocol> getPacketProtocol();
 
     /**
      * Returns true if the listener is listening.
      *
      * @return True if the listener is listening.
      */
-    public boolean isListening();
+    boolean isListening();
 
     /**
      * Gets this server's set flags.
      *
      * @return This server's flags.
      */
-    public Map<String, Object> getGlobalFlags();
+    Map<String, Object> getGlobalFlags();
 
     /**
      * Checks whether this server has a flag set.
@@ -51,7 +52,7 @@ public interface Server {
      * @param key Key of the flag to check for.
      * @return Whether this server has a flag set.
      */
-    public boolean hasGlobalFlag(String key);
+    boolean hasGlobalFlag(String key);
 
     /**
      * Gets the value of the given flag as an instance of the given type.
@@ -61,7 +62,7 @@ public interface Server {
      * @return Value of the flag.
      * @throws IllegalStateException If the flag's value isn't of the required type.
      */
-    public <T> T getGlobalFlag(String key);
+    <T> T getGlobalFlag(String key);
 
     /**
      * Gets the value of the given flag as an instance of the given type.
@@ -74,7 +75,7 @@ public interface Server {
      * @throws IllegalStateException If the flag's value isn't of the required type.
      */
     @SuppressWarnings("unchecked")
-    public <T> T getGlobalFlag(String key, T def);
+    <T> T getGlobalFlag(String key, T def);
 
     /**
      * Sets the value of a flag. The flag will be used in sessions if a session does
@@ -83,47 +84,47 @@ public interface Server {
      * @param key   Key of the flag.
      * @param value Value to set the flag to.
      */
-    public void setGlobalFlag(String key, Object value);
+    void setGlobalFlag(String key, Object value);
 
     /**
      * Gets the listeners listening on this session.
      *
      * @return This server's listeners.
      */
-    public List<ServerListener> getListeners();
+    List<ServerListener> getListeners();
 
     /**
      * Adds a listener to this server.
      *
      * @param listener Listener to add.
      */
-    public void addListener(ServerListener listener);
+    void addListener(ServerListener listener);
 
     /**
      * Removes a listener from this server.
      *
      * @param listener Listener to remove.
      */
-    public void removeListener(ServerListener listener);
+    void removeListener(ServerListener listener);
 
     /**
      * Gets all sessions belonging to this server.
      *
      * @return Sessions belonging to this server.
      */
-    public List<Session> getSessions();
+    List<Session> getSessions();
 
     /**
      * Binds the listener to its host and port.
      */
-    public AbstractServer bind();
+    AbstractServer bind();
 
     /**
      * Binds the listener to its host and port.
      *
      * @param wait Whether to wait for the listener to finish binding.
      */
-    public AbstractServer bind(boolean wait);
+    AbstractServer bind(boolean wait);
 
     /**
      * Binds the listener to its host and port.
@@ -131,19 +132,19 @@ public interface Server {
      * @param wait     Whether to wait for the listener to finish binding.
      * @param callback Callback to call when the listener has finished binding.
      */
-    public AbstractServer bind(boolean wait, Runnable callback);
+    AbstractServer bind(boolean wait, Runnable callback);
 
     /**
      * Closes the listener.
      */
-    public void close();
+    void close();
 
     /**
      * Closes the listener.
      *
      * @param wait Whether to wait for the listener to finish closing.
      */
-    public void close(boolean wait);
+    void close(boolean wait);
 
     /**
      * Closes the listener.
@@ -151,5 +152,5 @@ public interface Server {
      * @param wait     Whether to wait for the listener to finish closing.
      * @param callback Callback to call when the listener has finished closing.
      */
-    public void close(boolean wait, Runnable callback);
+    void close(boolean wait, Runnable callback);
 }

src/main/java/com/github/steveice10/packetlib/tcp/TcpServer.java

@@ -24,13 +24,14 @@ import io.netty.util.concurrent.Future;
 import io.netty.util.concurrent.GenericFutureListener;
 
 import java.net.InetSocketAddress;
+import java.util.function.Supplier;
 
 public class TcpServer extends AbstractServer {
     private EventLoopGroup group;
     private Class<? extends ServerSocketChannel> serverSocketChannel;
     private Channel channel;
 
-    public TcpServer(String host, int port, Class<? extends PacketProtocol> protocol) {
+    public TcpServer(String host, int port, Supplier<? extends PacketProtocol> protocol) {
         super(host, port, protocol);
     }