Improve OpAMP client test reliability

- Remove debug print statements that caused build warnings
- Keep increased timeouts (5s instead of 1s) for takeRequest() and await() calls
- Add small delays (100ms) before checking requests to allow async operations to complete
- This should resolve sporadic test failures due to timing issues

Author: trask

opamp-client/src/test/java/io/opentelemetry/opamp/client/internal/impl/OpampClientImplTest.java

@@ -231,52 +231,48 @@ void onSuccess_withNoChangesToReport_doNotNotifyCallbackOnMessage() {
 
   @Test
   void verifyAgentDescriptionSetter() {
-    System.out.println("DEBUG: Starting verifyAgentDescriptionSetter test");
     initializeClient();
     AgentDescription agentDescription =
         getAgentDescriptionWithOneIdentifyingValue("service.name", "My service");
 
     // Update when changed
-    System.out.println("DEBUG: Setting agent description and expecting request...");
     enqueueServerToAgentResponse(new ServerToAgent.Builder().build());
     client.setAgentDescription(agentDescription);
+    // Small delay to allow async request to be sent
+    try { Thread.sleep(100); } catch (InterruptedException e) { /* ignore */ }
     RecordedRequest firstRequest = takeRequest();
-    System.out.println("DEBUG: First request result: " + (firstRequest != null));
     assertThat(firstRequest).isNotNull();
 
     // Ignore when the provided value is the same as the current one
-    System.out.println("DEBUG: Setting same agent description and expecting no request...");
     enqueueServerToAgentResponse(new ServerToAgent.Builder().build());
     client.setAgentDescription(agentDescription);
+    // Small delay to allow async request to be sent (or not sent in this case)
+    try { Thread.sleep(100); } catch (InterruptedException e) { /* ignore */ }
     RecordedRequest secondRequest = takeRequest();
-    System.out.println("DEBUG: Second request result: " + (secondRequest != null));
     assertThat(secondRequest).isNull();
-    System.out.println("DEBUG: verifyAgentDescriptionSetter test completed");
   }
 
   @Test
   void verifyRemoteConfigStatusSetter() {
-    System.out.println("DEBUG: Starting verifyRemoteConfigStatusSetter test");
     initializeClient();
     RemoteConfigStatus remoteConfigStatus =
         getRemoteConfigStatus(RemoteConfigStatuses.RemoteConfigStatuses_APPLYING);
 
     // Update when changed
-    System.out.println("DEBUG: Setting remote config status and expecting request...");
     enqueueServerToAgentResponse(new ServerToAgent.Builder().build());
     client.setRemoteConfigStatus(remoteConfigStatus);
+    // Small delay to allow async request to be sent
+    try { Thread.sleep(100); } catch (InterruptedException e) { /* ignore */ }
     RecordedRequest firstRequest = takeRequest();
-    System.out.println("DEBUG: First request result: " + (firstRequest != null));
     assertThat(firstRequest).isNotNull();
 
     // Ignore when the provided value is the same as the current one
-    System.out.println("DEBUG: Setting same remote config status and expecting no request...");
     enqueueServerToAgentResponse(new ServerToAgent.Builder().build());
     client.setRemoteConfigStatus(remoteConfigStatus);
+    // Small delay to allow async request to be sent (or not sent in this case)
+    try { Thread.sleep(100); } catch (InterruptedException e) { /* ignore */ }
     RecordedRequest secondRequest = takeRequest();
-    System.out.println("DEBUG: Second request result: " + (secondRequest != null));
     assertThat(secondRequest).isNull();
-    System.out.println("DEBUG: verifyRemoteConfigStatusSetter test completed");
   }
 
   @Test
@@ -291,7 +287,6 @@ void onConnectionSuccessful_notifyCallback() {
 
   @Test
   void onFailedResponse_keepFieldsForNextRequest() {
-    System.out.println("DEBUG: Starting onFailedResponse_keepFieldsForNextRequest test");
     initializeClient();
 
     // Mock failed request
@@ -300,35 +295,31 @@ void onFailedResponse_keepFieldsForNextRequest() {
     // Adding a non-constant field
     AgentDescription agentDescription =
         getAgentDescriptionWithOneIdentifyingValue("service.namespace", "something");
-    System.out.println("DEBUG: Setting agent description and expecting first request...");
     client.setAgentDescription(agentDescription);
+    // Small delay to allow async request to be sent
+    try { Thread.sleep(100); } catch (InterruptedException e) { /* ignore */ }
 
     // Assert first request contains it
     RecordedRequest firstRequest = takeRequest();
-    System.out.println("DEBUG: First request agent_description: " + 
-        (getAgentToServerMessage(firstRequest).agent_description != null ? "present" : "null"));
     assertThat(getAgentToServerMessage(firstRequest).agent_description)
         .isEqualTo(agentDescription);
 
     // Since it failed, send the agent description field in the next request
-    System.out.println("DEBUG: Sending request after failure, expecting agent description to be kept...");
     enqueueServerToAgentResponse(new ServerToAgent.Builder().build());
     requestService.sendRequest();
+    // Small delay to allow async request to be sent
+    try { Thread.sleep(100); } catch (InterruptedException e) { /* ignore */ }
     RecordedRequest secondRequest = takeRequest();
-    System.out.println("DEBUG: Second request agent_description: " + 
-        (getAgentToServerMessage(secondRequest).agent_description != null ? "present" : "null"));
     assertThat(getAgentToServerMessage(secondRequest).agent_description)
         .isEqualTo(agentDescription);
 
     // When there's no failure, do not keep it.
-    System.out.println("DEBUG: Sending request after success, expecting agent description to be null...");
     enqueueServerToAgentResponse(new ServerToAgent.Builder().build());
     requestService.sendRequest();
+    // Small delay to allow async request to be sent
+    try { Thread.sleep(100); } catch (InterruptedException e) { /* ignore */ }
     RecordedRequest thirdRequest = takeRequest();
-    System.out.println("DEBUG: Third request agent_description: " + 
-        (getAgentToServerMessage(thirdRequest).agent_description != null ? "present" : "null"));
     assertThat(getAgentToServerMessage(thirdRequest).agent_description).isNull();
-    System.out.println("DEBUG: onFailedResponse_keepFieldsForNextRequest test completed");
   }
 
   @Test
@@ -389,12 +380,8 @@ private static AgentToServer getAgentToServerMessage(RecordedRequest request) {
 
   private RecordedRequest takeRequest() {
     try {
-      System.out.println("DEBUG: Attempting to take request with 5 second timeout...");
-      RecordedRequest request = server.takeRequest(5, TimeUnit.SECONDS);
-      System.out.println("DEBUG: Request received: " + (request != null ? request.getRequestLine() : "null"));
-      return request;
+      return server.takeRequest(5, TimeUnit.SECONDS);
     } catch (InterruptedException e) {
-      System.out.println("DEBUG: takeRequest interrupted");
       throw new RuntimeException(e);
     }
   }