Document java explicit span name with @WithSpan annotation (#6641)

Co-authored-by: Tiffany Hrabusa <[email protected]>
Co-authored-by: opentelemetrybot <[email protected]>

Author: 3 people

content/en/docs/zero-code/java/agent/annotations.md

@@ -60,8 +60,8 @@ public class MyClass {
 
 Each time the application invokes the annotated method, it creates a span that
 denotes its duration and provides any thrown exceptions. By default, the span
-name will be `<className>.<methodName>`, unless a name is provided as an
-argument to the annotation.
+name will be `<className>.<methodName>`, unless a name is provided through the
+`value` annotation parameter.
 
 If the return type of the method annotated by `@WithSpan` is one of the
 [future- or promise-like](https://en.wikipedia.org/wiki/Futures_and_promises)
@@ -87,16 +87,22 @@ customization of spans:
 
 | name             | type              | default    | description                                                                                                                                  |
 | ---------------- | ----------------- | ---------- | -------------------------------------------------------------------------------------------------------------------------------------------- |
+| `value`          | `String`          | `""`       | The span name. If not specified, the default `<className>.<methodName>` is used.                                                             |
 | `kind`           | `SpanKind` (enum) | `INTERNAL` | The [kind of span](/docs/specs/otel/trace/api/#spankind).                                                                                    |
 | `inheritContext` | `boolean`         | `true`     | Since 2.14.0. Controls whether or not the new span will be parented in the existing (current) context. If `false`, a new context is created. |
 
 Example parameter usage:
 
 ```java
-@WithSpan(kind = SpanKind.CLIENT, inheritContext = false)
+@WithSpan(kind = SpanKind.CLIENT, inheritContext = false, value = "my span name")
 public void myMethod() {
     <...>
 }
+
+@WithSpan("my span name")
+public void myOtherMethod() {
+    <...>
+}
 ```
 
 ## Adding attributes to the span with `@SpanAttribute`