small optimization with StringBuilder and String.format

src/main/java/me/neznamy/tab/shared/features/sorting/Sorting.java

@@ -106,18 +106,18 @@ private List<SortingType> compile(String string){
 	 * @return unique up to 16 character long sequence that sorts the player
 	 */
 	public String getTeamName(TabPlayer p) {
-		String teamName = "";
+		StringBuilder sb = new StringBuilder();
 		for (SortingType type : sorting) {
-			teamName += type.getChars(p);
+			sb.append(type.getChars(p));
 		}
-		if (teamName.length() > 12) {
-			teamName = teamName.substring(0, 12);
+		if (sb.length() > 12) {
+			sb.setLength(12);
 		}
-		teamName += p.getName();
-		if (teamName.length() > 15) {
-			teamName = teamName.substring(0, 15);
+		sb.append(p.getName());
+		if (sb.length() > 15) {
+			sb.setLength(15);
 		}
-		return checkTeamName(p, teamName, 65);
+		return checkTeamName(p, sb.toString(), 65);
 	}
 
 	/**

src/main/java/me/neznamy/tab/shared/features/sorting/types/Groups.java

@@ -26,10 +26,12 @@ public String getChars(TabPlayer p) {
 		String chars = sortedGroups.get(group.toLowerCase());
 		if (chars == null) {
 			chars = "9";
-			if (!group.equals("<null>")) TAB.getInstance().getErrorManager().oneTimeConsoleError("Group \"&e" + group + "&c\" is not defined in sorting list! This will result in players in that group not being sorted correctly. To fix this, add group \"&e" + group + "&c\" into &egroup-sorting-priority-list in config.yml&c. Your current list: " + sortedGroups.keySet());
+			if (!group.equals("<null>")) {
+				TAB.getInstance().getErrorManager().oneTimeConsoleError(String.format("Group \"&e%s&c\" is not defined in sorting list! This will result in players in that group not being sorted correctly. To fix this, add group \"&e%s&c\" into &egroup-sorting-priority-list in config.yml&c. Your current list: %s", group, group, sortedGroups.keySet()));
+			}
 			p.setTeamNameNote("&cPlayer's primary group is not in sorting list");
 		} else {
-			p.setTeamNameNote("Primary group is #" + Integer.parseInt(chars) + " in sorting list");
+			p.setTeamNameNote(String.format("Primary group is #%s in sorting list", Integer.parseInt(chars)));
 		}
 		return chars;
 	}