diff --git a/app/src/main/java/com/monke/monkeybook/utils/StringUtils.java b/app/src/main/java/com/monke/monkeybook/utils/StringUtils.java
index 998777e137..c6d2fa1657 100644
--- a/app/src/main/java/com/monke/monkeybook/utils/StringUtils.java
+++ b/app/src/main/java/com/monke/monkeybook/utils/StringUtils.java
@@ -218,7 +218,7 @@ public static String base64Decode(String str) {
     public static String escape(String src) {
         int i;
         char j;
-        StringBuffer tmp = new StringBuffer();
+        StringBuilder tmp = new StringBuilder();
         tmp.ensureCapacity(src.length() * 6);
         for (i = 0; i < src.length(); i++) {
             j = src.charAt(i);