Wire in a StringBuilder to avoid string concatenation.

1 files changed, 2 insertions, 2 deletions

diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/gbdtoptimization/GBDTNode.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/gbdtoptimization/GBDTNode.java
index 53a286f09f6..3c0898b5d4f 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/gbdtoptimization/GBDTNode.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/gbdtoptimization/GBDTNode.java
@@ -98,7 +98,7 @@ public final class GBDTNode extends ExpressionNode {
 
     /** Returns "(optimized condition tree)" */
     @Override
-    public String toString(SerializationContext context, Deque<String> path, CompositeNode parent) {
-        return "(optimized condition tree)";
+    public StringBuilder toString(StringBuilder string, SerializationContext context, Deque<String> path, CompositeNode parent) {
+        return string.append("(optimized condition tree)");
     }
 }