Use StringBuilder instead of StringBuffer (#10154)

2 files changed, 3 insertions, 3 deletions

diff --git a/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java b/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
index 04dc907799..fdcb578f01 100644
--- a/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
+++ b/server/src/main/java/com/vaadin/server/ComponentSizeValidator.java
@@ -124,7 +124,7 @@ public class ComponentSizeValidator implements Serializable {
     private static void printServerError(String msg,
             Deque<ComponentInfo> attributes, boolean widthError,
             PrintStream errorStream) {
-        StringBuffer err = new StringBuffer();
+        StringBuilder err = new StringBuilder();
         err.append("Vaadin DEBUG\n");
 
         StringBuilder indent = new StringBuilder();
@@ -369,7 +369,7 @@ public class ComponentSizeValidator implements Serializable {
     }
 
     private static void showComponent(Component component, String attribute,
-            StringBuffer err, StringBuilder indent, boolean widthError) {
+            StringBuilder err, StringBuilder indent, boolean widthError) {
 
         FileLocation createLoc = creationLocations.get(component);
 
diff --git a/server/src/main/java/com/vaadin/server/communication/ResourceWriter.java b/server/src/main/java/com/vaadin/server/communication/ResourceWriter.java
index 2cfc489c11..286e1475f2 100644
--- a/server/src/main/java/com/vaadin/server/communication/ResourceWriter.java
+++ b/server/src/main/java/com/vaadin/server/communication/ResourceWriter.java
@@ -79,7 +79,7 @@ public class ResourceWriter implements Serializable {
 
                 writer.write((resourceIndex++ > 0 ? ", " : "") + "\"" + resource
                         + "\" : ");
-                final StringBuffer layout = new StringBuffer();
+                final StringBuilder layout = new StringBuilder();
 
                 try (InputStreamReader r = new InputStreamReader(is,
                         StandardCharsets.UTF_8)) {