fix(gax): update resource name extraction across tests and goldens

Author: blakeli0

gapic-generator-java/src/main/java/com/google/api/generator/gapic/composer/common/AbstractTransportServiceStubClassComposer.java

@@ -1505,6 +1505,10 @@ private static Predicate<String> shouldAutoPopulate(Message methodRequestMessage
             .anyMatch(field -> field.name().equals(fieldName) && field.canBeAutoPopulated());
   }
 
+  /**
+   * The Resource Name Extractor should only be generated if the request contains a field that has
+   * resource reference (see {@link Field#hasResourceReference()})
+   */
   @Nullable
   protected static LambdaExpr createResourceNameExtractorClassInstance(
       Method method, ImmutableMap<String, Message> messageTypes) {
@@ -1514,6 +1518,7 @@ protected static LambdaExpr createResourceNameExtractorClassInstance(
       return null;
     }
 
+    // Expected expression: request -> request.getField()
     VariableExpr requestVarExpr = createRequestVarExpr(method);
     List<Statement> bodyStatements = new ArrayList<>();
     Expr returnExpr =
@@ -1531,6 +1536,7 @@ protected static LambdaExpr createResourceNameExtractorClassInstance(
         .build();
   }
 
+  // Find the first field that has resource reference in a request message
   private static Field getDestinationResourceIdField(
       Method method, ImmutableMap<String, Message> messageTypes) {
     if (method.inputType().reference() == null
@@ -1544,7 +1550,8 @@ private static Field getDestinationResourceIdField(
     }
 
     return methodRequestMessage.fields().stream()
-        .filter(f -> f.resourceReference() != null && !f.isRepeated())
+        .filter(Field::hasResourceReference)
+        .filter(f -> !f.isRepeated())
         .findFirst()
         .orElse(null);
   }

gax-java/gax/src/main/java/com/google/api/gax/tracing/TracedUnaryCallable.java

@@ -67,13 +67,6 @@ public TracedUnaryCallable(
     this.resourceNameExtractor = null;
   }
 
-  public TracedUnaryCallable(
-      UnaryCallable<RequestT, ResponseT> innerCallable,
-      ApiTracerFactory tracerFactory,
-      ApiTracerContext apiTracerContext) {
-    this(innerCallable, tracerFactory, apiTracerContext, null);
-  }
-
   public TracedUnaryCallable(
       UnaryCallable<RequestT, ResponseT> innerCallable,
       ApiTracerFactory tracerFactory,

gax-java/gax/src/test/java/com/google/api/gax/tracing/TracedUnaryCallableTest.java

@@ -80,7 +80,8 @@ void init(boolean useContext) {
     if (useContext) {
       when(tracerFactory.newTracer(any(ApiTracer.class), any(ApiTracerContext.class)))
           .thenReturn(tracer);
-      tracedUnaryCallable = new TracedUnaryCallable<>(innerCallable, tracerFactory, TRACER_CONTEXT);
+      tracedUnaryCallable =
+          new TracedUnaryCallable<>(innerCallable, tracerFactory, TRACER_CONTEXT, null);
     } else {
       when(tracerFactory.newTracer(
               any(ApiTracer.class), any(SpanName.class), eq(OperationType.Unary)))
@@ -111,12 +112,13 @@ void testTracerCreated(boolean useContext) {
   void testOperationTypeIsSet() {
     when(tracerFactory.newTracer(any(ApiTracer.class), any(ApiTracerContext.class)))
         .thenReturn(tracer);
-    tracedUnaryCallable = new TracedUnaryCallable<>(innerCallable, tracerFactory, TRACER_CONTEXT);
+    tracedUnaryCallable =
+        new TracedUnaryCallable<>(innerCallable, tracerFactory, TRACER_CONTEXT, null);
     ApiTracerContext contextWithWrongType =
         TRACER_CONTEXT.toBuilder().setOperationType(OperationType.BidiStreaming).build();
 
     tracedUnaryCallable =
-        new TracedUnaryCallable<>(innerCallable, tracerFactory, contextWithWrongType);
+        new TracedUnaryCallable<>(innerCallable, tracerFactory, contextWithWrongType, null);
 
     innerResult = SettableApiFuture.create();
     when(innerCallable.futureCall(anyString(), any(ApiCallContext.class))).thenReturn(innerResult);
@@ -209,7 +211,8 @@ void testResourceNameExtractorUsed() {
 
   @Test
   void testExtractResourceNameToApiTracerContext_nullExtractor() {
-    tracedUnaryCallable = new TracedUnaryCallable<>(innerCallable, tracerFactory, TRACER_CONTEXT);
+    tracedUnaryCallable =
+        new TracedUnaryCallable<>(innerCallable, tracerFactory, TRACER_CONTEXT, null);
     ApiTracerContext context = tracedUnaryCallable.extractResourceNameToApiTracerContext("request");
     assertThat(context).isEqualTo(TRACER_CONTEXT);
   }