configure method parallelism for slow tests

Author: sakthivelmanii

samples/snippets/pom.xml

@@ -159,6 +159,10 @@
             <configuration>
               <forkCount>10</forkCount>
               <reuseForks>false</reuseForks>
+              <parallel>classesAndMethods</parallel>
+              <threadCount>5</threadCount>
+              <threadCountClasses>2</threadCountClasses>
+              <threadCountMethods>3</threadCountMethods>
               <systemPropertyVariables>
                 <spanner.test.instance>java-sample-integration-tests</spanner.test.instance>
                 <spanner.test.instance.mr>java-client-mr-integration-tests</spanner.test.instance.mr>

samples/snippets/src/test/java/com/example/spanner/SpannerSampleIT.java

@@ -43,6 +43,7 @@
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.PrintStream;
+import java.time.Duration;
 import java.util.UUID;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Predicate;
@@ -590,6 +591,7 @@ public void testEncryptedDatabaseAndBackupSamples() throws Exception {
     } finally {
       // Delete the backups from the test instance first, as the instance can only be deleted once
       // all backups have been deleted.
+      Uninterruptibles.sleepUninterruptibly(Duration.ofMinutes(1));
       System.out.println("Deleting backups ...");
       deleteAllBackups(instanceId);
       instanceAdminClient.deleteInstance(instanceId);
@@ -752,15 +754,21 @@ static String formatForTest(String name) {
 
   static class ShouldRetryBackupOperation implements Predicate<SpannerException> {
 
-    private static final int MAX_ATTEMPTS = 20;
+    private int maxAttempts = 20;
     private int attempts = 0;
 
+    ShouldRetryBackupOperation() {}
+
+    ShouldRetryBackupOperation(int maxAttempts) {
+      this.maxAttempts = maxAttempts;
+    }
+
     @Override
     public boolean test(SpannerException e) {
       if (e.getErrorCode() == ErrorCode.FAILED_PRECONDITION
           && e.getMessage().contains("Please retry the operation once the pending")) {
         attempts++;
-        if (attempts == MAX_ATTEMPTS) {
+        if (attempts == maxAttempts) {
           // Throw custom exception so it is easier to locate in the log why it went wrong.
           throw SpannerExceptionFactory.newSpannerException(
               ErrorCode.DEADLINE_EXCEEDED,
@@ -770,6 +778,7 @@ public boolean test(SpannerException e) {
                   attempts),
               e);
         }
+        System.out.println("Attempt " + attempts);
         // Wait one minute before retrying.
         Uninterruptibles.sleepUninterruptibly(60L, TimeUnit.SECONDS);
         return true;