test: improve coverage

Author: diegomarquezp

gax-java/gax-httpjson/src/test/java/com/google/api/gax/httpjson/BodySizeRecordingTest.java

@@ -38,6 +38,7 @@
 import com.google.api.gax.rpc.StreamController;
 import com.google.auth.Credentials;
 import com.google.protobuf.Field;
+import java.nio.charset.StandardCharsets;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -142,6 +143,8 @@ void testBodySizeRecording() throws Exception {
     String expectedResponseBody = ProtoRestSerializer.create().toBody("*", response, false);
     long expectedResponseSize = expectedResponseBody.getBytes("UTF-8").length;
     assertThat(tracer.getResponseReceivedSize()).isEqualTo(expectedResponseSize);
+    // Unary calls should NOT call responseReceived() (reserved for streaming)
+    assertThat(tracer.getResponsesReceived()).isEqualTo(0);
   }
 
   @Test
@@ -218,9 +221,11 @@ public void onComplete() {
     String resp1Json = methodServerStreaming.getResponseParser().serialize(response1);
     String resp2Json = methodServerStreaming.getResponseParser().serialize(response2);
     long expectedTotalResponseSize =
-        ("[" + resp1Json + "," + resp2Json + "]").getBytes("UTF-8").length;
+        ("[" + resp1Json + "," + resp2Json + "]").getBytes(StandardCharsets.UTF_8).length;
 
     assertThat(tracer.getResponseReceivedSize()).isEqualTo(expectedTotalResponseSize);
+    // Server-streaming calls should call responseReceived() for EACH message
+    assertThat(tracer.getResponsesReceived()).isEqualTo(2);
     streamingChannel.shutdownNow();
   }
 }

gax-java/gax-httpjson/src/test/java/com/google/api/gax/httpjson/testing/TestApiTracer.java

@@ -45,6 +45,7 @@ public class TestApiTracer implements ApiTracer {
   private final AtomicInteger attemptsFailed = new AtomicInteger();
   private final AtomicBoolean retriesExhausted = new AtomicBoolean(false);
   private final AtomicLong responseReceivedSize = new AtomicLong();
+  private final AtomicInteger responsesReceived = new AtomicInteger();
 
   public TestApiTracer() {}
 
@@ -64,6 +65,10 @@ public long getResponseReceivedSize() {
     return responseReceivedSize.get();
   }
 
+  public int getResponsesReceived() {
+    return responsesReceived.get();
+  }
+
   @Override
   public void attemptStarted(int attemptNumber) {
     attemptsStarted.incrementAndGet();
@@ -85,6 +90,11 @@ public void attemptFailedRetriesExhausted(Throwable error) {
     retriesExhausted.set(true);
   }
 
+  @Override
+  public void responseReceived() {
+    responsesReceived.incrementAndGet();
+  }
+
   @Override
   public void recordResponseSize(long responseSize) {
     responseReceivedSize.addAndGet(responseSize);