Update source code to match v1.1

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>me.masterbro</groupId>
     <artifactId>TesterUtils</artifactId>
-    <version>1.0</version>
+    <version>1.1</version>
     <packaging>jar</packaging>
 
     <name>TesterUtils</name>

src/main/java/me/masterbro/testerutils/commands/DestroyEntityCommand.java

@@ -13,20 +13,30 @@
 import java.util.List;
 
 public class DestroyEntityCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
-        if(!(sender instanceof Player)) {
-            sender.sendMessage("This command can only be used in-game.");
+    private boolean entityTypeExists(String string) {
+        try {
+            EntityType.valueOf(string);
             return true;
+        } catch(IllegalArgumentException exception) {
+            return false;
         }
+    }
 
+    @Override
+    public boolean onCommand(CommandSender sender, Command command, String label, String[] args) {
         Player player = (Player) sender;
 
         if(args.length == 0) {
             player.sendMessage("Error: No arguments provided.");
             player.sendMessage("Correct usage: /destroyentity <worldName> <entityType>");
         } else {
 
+            if(!entityTypeExists(args[1])) {
+                player.sendMessage("Error: The entity type that was specified doesn't exist.");
+                player.sendMessage("Please check the spelling and try again.");
+                return true;
+            }
+
             EntityType entityType = EntityType.valueOf(args[1]);
 
             String worldName = args[0];