Added Registerable interface.

pom.xml

@@ -11,7 +11,7 @@
 	</properties>
 	
 	<build>
-		<defaultGoal>clean install</defaultGoal>
+		<defaultGoal>install</defaultGoal>
 		<finalName>MassiveCore</finalName>
 		<sourceDirectory>${basedir}/src/main/java/</sourceDirectory>
 		<resources>

src/main/java/com/massivecraft/massivecore/PredictateIsRegistered.java

@@ -0,0 +1,22 @@
+package com.massivecraft.massivecore;
+
+public class PredictateIsRegistered implements Predictate<Registerable>
+{
+	// -------------------------------------------- //
+	// INSTANCE & CONSTRUCT
+	// -------------------------------------------- //
+	
+	private static PredictateIsRegistered i = new PredictateIsRegistered();
+	public static PredictateIsRegistered get() { return i; }
+	
+	// -------------------------------------------- //
+	// OVERRIDE
+	// -------------------------------------------- //
+
+	@Override
+	public boolean apply(Registerable registerable)
+	{
+		return registerable.isRegistered();
+	}
+	
+}

src/main/java/com/massivecraft/massivecore/Registerable.java

@@ -0,0 +1,6 @@
+package com.massivecraft.massivecore;
+
+public interface Registerable
+{
+	public boolean isRegistered();
+}