Add Convenience method for tab-completion and correct indentation.

NCPCore/src/main/java/fr/neatmonster/nocheatplus/command/CommandUtil.java

@@ -4,6 +4,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashSet;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 
@@ -128,4 +129,29 @@ public class CommandUtil {
         }
         return null;
     }
+    
+    /**
+     * Convenience method to map all matches within one of the String[] arrays
+     * to its first element.<br>
+     * Do note that this does exact-case comparison, for case insensitive
+     * comparison use a lower-case model and pass a lower-case input.
+     * 
+     * @param input
+     * @param model
+     *            Should be lower case (!).
+     * @return Always returns a modifiable list.
+     */
+    public static List<String> getTabMatches(final String input, final String[][] model) {
+        final List<String> res = new LinkedList<String>();
+        for (final String[] choices : model) {
+            for (final String choice : choices) {
+                if (choice.startsWith(input)) {
+                    res.add(choices[0]);
+                    break;
+                }
+            }
+        }
+        return res;
+    }
+
 }