diff --git a/common/src/main/java/io/netty/util/internal/AppendableCharSequence.java b/common/src/main/java/io/netty/util/internal/AppendableCharSequence.java
index 3d3373ec80..408c32f380 100644
--- a/common/src/main/java/io/netty/util/internal/AppendableCharSequence.java
+++ b/common/src/main/java/io/netty/util/internal/AppendableCharSequence.java
@@ -68,12 +68,12 @@ public final class AppendableCharSequence implements CharSequence, Appendable {
 
     @Override
     public AppendableCharSequence append(char c) {
-        try {
-            chars[pos++] = c;
-        } catch (IndexOutOfBoundsException e) {
-            expand();
-            chars[pos - 1] = c;
+        if (pos == chars.length) {
+            char[] old = chars;
+            chars = new char[old.length << 1];
+            System.arraycopy(old, 0, chars, 0, old.length);
         }
+        chars[pos++] = c;
         return this;
     }
 
@@ -139,17 +139,6 @@ public final class AppendableCharSequence implements CharSequence, Appendable {
         return new String(chars, start, end - start);
     }
 
-    private void expand() {
-        char[] old = chars;
-        // double it
-        int len = old.length << 1;
-        if (len < 0) {
-            throw new IllegalStateException();
-        }
-        chars = new char[len];
-        System.arraycopy(old, 0, chars, 0, old.length);
-    }
-
     private static char[] expand(char[] array, int neededSpace, int size) {
         int newCapacity = array.length;
         do {