ExceptionSet equals and hash code. MetadataSimple improvements.

src/com/massivecraft/massivecore/MetadataSimple.java

@@ -47,22 +47,36 @@ public class MetadataSimple extends MetadataValueAdapter
 	
 	public static void set(Plugin plugin, Metadatable metadatable, String key, Object value)
 	{
-		metadatable.setMetadata(key, new MetadataSimple(plugin, value));
+		if (value != null)
+		{
+			metadatable.setMetadata(key, new MetadataSimple(plugin, value));
+		}
+		else
+		{
+			metadatable.removeMetadata(key, plugin);
+		}
 	}
 	
 	public static MetadataValue getMeta(Metadatable metadatable, String key)
 	{
+		if (metadatable == null) return null;
 		List<MetadataValue> metaValues = metadatable.getMetadata(key);
 		if (metaValues == null) return null;
-		if (metaValues.size() < 1) return null;
+		if (metaValues.isEmpty()) return null;
 		return metaValues.get(0);
 	}
 	
-	public static Object get(Metadatable metadatable, String key)
+	@SuppressWarnings("unchecked")
+	public static <T> T get(Metadatable metadatable, String key)
 	{
 		MetadataValue metaValue = getMeta(metadatable, key);
 		if (metaValue == null) return null;
-		return metaValue.value();
+		return (T) metaValue.value();
+	}
+	
+	public static boolean has(Metadatable metadatable, String key)
+	{
+		return get(metadatable, key) != null;
 	}
 	
 }

src/com/massivecraft/massivecore/collections/ExceptionSet.java

@@ -2,10 +2,12 @@ package com.massivecraft.massivecore.collections;
 
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Objects;
 
 import com.massivecraft.massivecore.command.editor.annotation.EditorType;
 import com.massivecraft.massivecore.command.type.container.TypeMassiveTreeSetInsensitive;
 import com.massivecraft.massivecore.comparator.ComparatorCaseInsensitive;
+import com.massivecraft.massivecore.util.MUtil;
 
 public class ExceptionSet
 {
@@ -104,4 +106,29 @@ public class ExceptionSet
 		return ret;
 	}
 	
+	// -------------------------------------------- //
+	// EQUALS & HASH CODE
+	// -------------------------------------------- //
+	
+	@Override
+	public boolean equals(Object object)
+	{
+		if ( ! (object instanceof ExceptionSet)) return false;
+		ExceptionSet that = (ExceptionSet)object;
+		
+		return MUtil.equals(
+			this.standard, that.standard,
+			this.exceptions, that.exceptions
+		);
+	}
+	
+	@Override
+	public int hashCode()
+	{
+		return Objects.hash(
+			this.standard,
+			this.exceptions
+		);
+	}
+	
 }