Add debug print statements to diagnose why server is not starting.

Author: kannanjgithub

interop-testing/src/main/java/io/grpc/testing/integration/TestServiceServer.java

@@ -156,6 +156,8 @@ void parseArgs(String[] args) {
   @SuppressWarnings("AddressSelection")
   @VisibleForTesting
   void start() throws Exception {
+    System.out.println("TestServiceServer.start() called with addressType " + addressType);
+    System.out.flush();
     executor = Executors.newSingleThreadScheduledExecutor();
     ServerCredentials serverCreds;
     if (useAlts) {
@@ -194,6 +196,8 @@ void start() throws Exception {
           ((NettyServerBuilder) serverBuilder).addListenAddress(v4Address);
         }
         if (setMcsLimit) {
+          System.out.println("TestServiceServer.start() setting mcs limit to 2.");
+          System.out.flush();
           ((NettyServerBuilder) serverBuilder).maxConcurrentCallsPerConnection(2);
         }
         break;
@@ -211,6 +215,8 @@ void start() throws Exception {
       default:
         throw new AssertionError("Unknown address type: " + addressType);
     }
+    System.out.println("TestServiceServer.start() calling serverBuilder start.");
+    System.out.flush();
     server = serverBuilder
         .maxInboundMessageSize(AbstractInteropTest.MAX_MESSAGE_SIZE)
         .addService(
@@ -220,6 +226,8 @@ void start() throws Exception {
         .intercept(OrcaMetricReportingServerInterceptor.create(metricRecorder))
         .build()
         .start();
+    System.out.println("TestServiceServer.start() after calling serverBuilder start.");
+    System.out.flush();
   }
 
   @VisibleForTesting