Do not allow a block with an Essentials Sign attached to it to be pul…

…led with a sticky piston

Essentials/src/com/earth2me/essentials/EssentialsBlockListener.java

@@ -1,16 +1,17 @@
 package com.earth2me.essentials;
 
+import com.earth2me.essentials.signs.EssentialsSign;
 import com.earth2me.essentials.utils.LocationUtil;
 import java.util.Locale;
 import net.ess3.api.IEssentials;
 import org.bukkit.GameMode;
 import org.bukkit.Material;
-import org.bukkit.block.BlockState;
-import org.bukkit.block.CreatureSpawner;
+import org.bukkit.block.*;
 import org.bukkit.entity.EntityType;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.EventPriority;
 import org.bukkit.event.Listener;
+import org.bukkit.event.block.BlockPistonRetractEvent;
 import org.bukkit.event.block.BlockPlaceEvent;
 import org.bukkit.inventory.ItemStack;
 
@@ -68,4 +69,26 @@ public void run()
 			});
 		}
 	}
+
+	@EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+	public void onBlockPistonRetract(BlockPistonRetractEvent event)
+	{
+		final Block block = event.getRetractLocation().getBlock();
+		for (BlockFace face : new BlockFace[] { BlockFace.NORTH, BlockFace.EAST, BlockFace.WEST, BlockFace.SOUTH, BlockFace.UP })
+		{
+			final Block search = block.getRelative(face, 1);
+			final Material type = search.getType();
+			if (type == Material.SIGN || type == Material.SIGN_POST)
+			{
+				final Sign sign = (Sign)(search.getState());
+				for (final EssentialsSign esign : ess.getSettings().enabledSigns())
+				{
+					if (sign.getLine(0).equalsIgnoreCase(esign.getSuccessName()))
+					{
+						event.setCancelled(true);
+					}
+				}
+			}
+		}
+	}
 }