1 files changed, 3 insertions, 3 deletions
diff --git a/src/main/javassist/bytecode/analysis/ControlFlow.java b/src/main/javassist/bytecode/analysis/ControlFlow.java
index e47c00d3..46b82dbf 100644
--- a/src/main/javassist/bytecode/analysis/ControlFlow.java
+++ b/src/main/javassist/bytecode/analysis/ControlFlow.java
@@ -261,13 +261,13 @@ public class ControlFlow {
         }
 
         @Override
-        protected void toString2(StringBuffer sbuf) {
+        protected void toString2(StringBuilder sbuf) {
             super.toString2(sbuf);
             sbuf.append(", incoming{");
             for (int i = 0; i < entrances.length; i++)
                     sbuf.append(entrances[i].position).append(", ");
 
-            sbuf.append("}");
+            sbuf.append('}');
         }
 
         BasicBlock[] getExit() { return exit; }
@@ -360,7 +360,7 @@ public class ControlFlow {
          */
         @Override
         public String toString() {
-            StringBuffer sbuf = new StringBuffer();
+            StringBuilder sbuf = new StringBuilder();
             sbuf.append("Node[pos=").append(block().position());
             sbuf.append(", parent=");
             sbuf.append(parent == null ? "*" : Integer.toString(parent.block().position()));