fix: remove recursive error logic in SpanTracer

Author: diegomarquezp

sdk-platform-java/gax-java/gax/src/main/java/com/google/api/gax/tracing/SpanTracer.java

@@ -30,6 +30,7 @@
 
 package com.google.api.gax.tracing;
 
+import com.google.api.client.util.Strings;
 import com.google.api.core.BetaApi;
 import com.google.api.core.InternalApi;
 import io.opentelemetry.api.trace.Span;
@@ -218,14 +219,10 @@ private void recordErrorAndEndAttempt(Throwable error) {
   }
 
   private String extractErrorMessage(Throwable error) {
-    Throwable cause = error;
-    while (cause != null) {
-      if (cause.getMessage() != null && !cause.getMessage().isEmpty()) {
-        return cause.getMessage();
-      }
-      cause = cause.getCause();
+    if (Strings.isNullOrEmpty(error.getMessage())) {
+      return null;
     }
-    return null;
+    return error.getMessage();
   }
 
   private void endAttempt() {

sdk-platform-java/gax-java/gax/src/test/java/com/google/api/gax/tracing/SpanTracerTest.java

@@ -456,23 +456,6 @@ void testAttemptFailed_populatesExceptionTypeAndMessage() {
     verify(span).end();
   }
 
-  @Test
-  void testAttemptFailed_recursiveMessageSearch() {
-    spanTracer.attemptStarted(new Object(), 1);
-
-    Throwable cause = new IllegalArgumentException("root cause message");
-    Throwable wrapper = new IllegalStateException("", cause);
-
-    spanTracer.attemptFailedRetriesExhausted(wrapper);
-
-    verify(span)
-        .setAttribute(
-            ObservabilityAttributes.EXCEPTION_TYPE_ATTRIBUTE, "java.lang.IllegalStateException");
-    verify(span)
-        .setAttribute(ObservabilityAttributes.STATUS_MESSAGE_ATTRIBUTE, "root cause message");
-    verify(span).end();
-  }
-
   private static class RedirectException extends RuntimeException {
     public RedirectException(String message) {
       super(message);