Cache Part Constructor.

items/parts/ItemMultiPart.java

@@ -191,7 +191,12 @@ public class ItemMultiPart extends AEBaseItem implements IPartItem, IItemGroup
 		{
 			PartType t = getTypeByStack( is );
 			if ( t != null )
-				return t.getPart().getConstructor( ItemStack.class ).newInstance( is );
+			{
+				if ( t.constructor == null )
+					t.constructor = t.getPart().getConstructor( ItemStack.class );
+
+				return t.constructor.newInstance( is );
+			}
 		}
 		catch (Throwable e)
 		{

items/parts/PartType.java

@@ -1,5 +1,6 @@
 package appeng.items.parts;
 
+import java.lang.reflect.Constructor;
 import java.util.EnumSet;
 
 import appeng.api.parts.IPart;
@@ -112,6 +113,8 @@ public enum PartType
 	private final GuiText extraName;
 	public final int baseDamage;
 
+	public Constructor<? extends IPart> constructor;
+
 	PartType(int baseMetaValue, AEFeature part, Class<? extends IPart> c) {
 		this( baseMetaValue, part, c, null );
 	}