diff --git a/src/main/java/com/github/nkzawa/socketio/parser/Parser.java b/src/main/java/com/github/nkzawa/socketio/parser/Parser.java
index a6138b8..e6f15fa 100644
--- a/src/main/java/com/github/nkzawa/socketio/parser/Parser.java
+++ b/src/main/java/com/github/nkzawa/socketio/parser/Parser.java
@@ -169,7 +169,7 @@ public class Parser {
             }
         }
 
-        public static Packet decodeString(String str) {
+        private static Packet decodeString(String str) {
             Packet p = new Packet();
             int i = 0;