SONARJAVA-5602: Modify rule S3033, benchmark performance with respect to StringBuilder size

rules/S3033/java/rule.adoc

@@ -35,27 +35,37 @@ if (sb.isEmpty()) {
 
 [options="header"]
 |===
-| Method| Runtime| Average time| Error margin
-| isEmpty| Temurin 21| 6.60 ns/op| ±0.58 ns/op
-| length| Temurin 21| 6.89 ns/op| ±0.22 ns/op
-| toStringEquals| Temurin 21| 10.90 ns/op| ±0.62 ns/op
-| toStringIsEmpty| Temurin 21| 11.07 ns/op| ±0.94 ns/op
+| Method| stringBuilderSize| Runtime| Average time| Error margin
+| isEmpty| 10| Temurin 21| 6.57 ns/op| ±0.38 ns/op
+| isEmpty| 100| Temurin 21| 6.68 ns/op| ±0.10 ns/op
+| isEmpty| 1000| Temurin 21| 6.80 ns/op| ±0.12 ns/op
+| length| 10| Temurin 21| 6.83 ns/op| ±0.12 ns/op
+| length| 100| Temurin 21| 6.66 ns/op| ±0.11 ns/op
+| length| 1000| Temurin 21| 6.67 ns/op| ±0.07 ns/op
+| toStringEquals| 10| Temurin 21| 13.92 ns/op| ±0.18 ns/op
+| toStringEquals| 100| Temurin 21| 59.09 ns/op| ±0.53 ns/op
+| toStringEquals| 1000| Temurin 21| 465.79 ns/op| ±5.86 ns/op
+| toStringIsEmpty| 10| Temurin 21| 13.83 ns/op| ±0.23 ns/op
+| toStringIsEmpty| 100| Temurin 21| 60.06 ns/op| ±3.42 ns/op
+| toStringIsEmpty| 1000| Temurin 21| 484.58 ns/op| ±4.24 ns/op
 |===
 
+*Benchmarking code*
 
-The results were generated by running the following snippet with https://github.com/openjdk/jmh[JMH]:
+The results were generated by running the following snippet with https://github.com/openjdk/jmh[JMH].
 
 [source,java]
 ----
-private String[] str = {"a", "b", "c", "d", "e"};
-private StringBuilder sb = new StringBuilder();
+@Param({"10", "100", "1000"})
+int stringBuilderSize;
+
+
+private StringBuilder sb;
 
 @Setup(Level.Iteration)
 public void setup() {
   sb = new StringBuilder();
-  for (String s : str) {
-    sb.append(s);
-  }
+  IntStream.range(0, stringBuilderSize).forEach(i -> sb.append("word"));
 }
 
 @Benchmark