SONARJAVA-5580 modify S3024: add performance benchmark table

rules/S3024/java/rule.adoc

@@ -5,7 +5,7 @@ The use of a ``++StringBuilder++`` or ``++StringBuffer++`` is supposed to make `
 
 === Noncompliant code example
 
-[source,java]
+[source,java,diff-id=1,diff-type=noncompliant]
 ----
 StringBuilder sb = new StringBuilder();
 sb.append("foo is: " + getFoo()); // Noncompliant
@@ -14,12 +14,46 @@ sb.append("foo is: " + getFoo()); // Noncompliant
 
 === Compliant solution
 
-[source,java]
+[source,java,diff-id=2,diff-type=compliant]
 ----
 StringBuilder sb = new StringBuilder();
 sb.append("foo is: ").append(getFoo());
 ----
 
+== Resources
+
+=== Benchmarks
+
+[options="header"]
+|===
+| method| Runtime| Average time| Error margin
+| append| Temurin 21| 26.3 ns/op| ±0.43 ns/op
+| concat| Temurin 21| 30.3 ns/op| ±0.81 ns/op
+|===
+
+The results were generated by running the following snippet with https://github.com/openjdk/jmh[jmh]:
+
+[source,java]
+----
+private String name1 = "John";
+private String name2 = "Jane";
+
+@Benchmark
+public String concat() {
+  StringBuilder sb = new StringBuilder();
+  sb.append(name1 + ", " + name2);
+  return sb.toString();
+}
+
+@Benchmark
+public String append() {
+  StringBuilder sb = new StringBuilder();
+  sb.append(name1).append(", ").append(name2);
+  return sb.toString();
+}
+----
+
+
 ifdef::env-github,rspecator-view[]
 
 '''