Retry again if the hack isn't ready.

ProtocolLib/src/main/java/com/comphenix/protocol/injector/player/PlayerInjector.java

@@ -24,6 +24,7 @@ import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.net.Socket;
 import java.net.SocketAddress;
+import java.util.concurrent.Callable;
 
 import net.sf.cglib.proxy.Factory;
 
@@ -100,7 +101,7 @@ abstract class PlayerInjector {
 	protected ErrorReporter reporter;
 
 	// Scheduled action on the next packet event
-	protected Runnable scheduledAction;
+	protected Callable<Boolean> scheduledAction;
 
 	// Whether or not the injector has been cleaned
 	private boolean clean;
@@ -519,9 +520,16 @@ abstract class PlayerInjector {
 			
 			// Hack #1: Handle a single scheduled action
 			if (scheduledAction != null) {
-				scheduledAction.run();
+				try {
+					if (scheduledAction.call()) {
 						scheduledAction = null;
 					}
+				} catch (Exception e) {
+					reporter.reportDetailed(this, "Cannot perform hack #1.", e, scheduledAction, packet);
+					scheduledAction = null;
+				}
+			}
+			
 			// Hack #2
 			if (updateOnLogin) {
 				if (id == Packets.Server.LOGIN) {
@@ -595,9 +603,11 @@ abstract class PlayerInjector {
 	
 	/**
 	 * Schedule an action to occur on the next sent packet.
+	 * <p>
+	 * If the callable returns TRUE, the action is removed.
 	 * @param action - action to execute.
 	 */
-	public void scheduleAction(Runnable action) {
+	public void scheduleAction(Callable<Boolean> action) {
 		scheduledAction = action;
 	}
 

ProtocolLib/src/main/java/com/comphenix/protocol/injector/player/ProxyPlayerInjectionHandler.java

@@ -24,6 +24,7 @@ import java.net.Socket;
 import java.net.SocketAddress;
 import java.util.Map;
 import java.util.Set;
+import java.util.concurrent.Callable;
 import java.util.concurrent.TimeUnit;
 
 import org.bukkit.Server;
@@ -663,10 +664,17 @@ class ProxyPlayerInjectionHandler implements PlayerInjectionHandler {
 
 		// Update the DataInputStream
 		if (injector != null) {
-			injector.scheduleAction(new Runnable() {
+			injector.scheduleAction(new Callable<Boolean>() {
 				@Override
-				public void run() {
+				public Boolean call() throws Exception {
-					dataInputLookup.put(injector.getInputStream(false), injector);
+					DataInputStream inputStream = injector.getInputStream(false);
+					
+					if (inputStream != null) {
+						dataInputLookup.put(inputStream, injector);
+						return true;
+					} 
+					// Try again
+					return false;
 				}
 			});
 		}