diff --git a/cas/1.0/default/TypeConvert.cpp b/cas/1.0/default/TypeConvert.cpp
index cd0efdb..cc25cf5 100644
--- a/cas/1.0/default/TypeConvert.cpp
+++ b/cas/1.0/default/TypeConvert.cpp
@@ -82,7 +82,7 @@
     for (size_t i = 0; i < sessionId.size(); i++) {
         result.appendFormat("%02x ", sessionId[i]);
     }
-    if (result.isEmpty()) {
+    if (result.empty()) {
         result.append("(null)");
     }
     return result;
diff --git a/cas/1.1/default/TypeConvert.cpp b/cas/1.1/default/TypeConvert.cpp
index 09ef41a..2ffc79a 100644
--- a/cas/1.1/default/TypeConvert.cpp
+++ b/cas/1.1/default/TypeConvert.cpp
@@ -81,7 +81,7 @@
     for (size_t i = 0; i < sessionId.size(); i++) {
         result.appendFormat("%02x ", sessionId[i]);
     }
-    if (result.isEmpty()) {
+    if (result.empty()) {
         result.append("(null)");
     }
     return result;
diff --git a/cas/1.2/default/TypeConvert.cpp b/cas/1.2/default/TypeConvert.cpp
index c4bd0dd..7d27fa1 100644
--- a/cas/1.2/default/TypeConvert.cpp
+++ b/cas/1.2/default/TypeConvert.cpp
@@ -108,7 +108,7 @@
     for (size_t i = 0; i < sessionId.size(); i++) {
         result.appendFormat("%02x ", sessionId[i]);
     }
-    if (result.isEmpty()) {
+    if (result.empty()) {
         result.append("(null)");
     }
     return result;