Add mock ScheduledExecutorService

pom.xml

@@ -143,6 +143,12 @@
       <artifactId>jersey-test-framework-provider-jetty</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-core</artifactId>
+      <version>2.2.0</version>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>

src/test/java/io/jenkins/plugins/services/DatastoreServiceIntegrationTest.java

@@ -10,25 +10,31 @@ import org.junit.AfterClass;
 import org.junit.Assert;
 import org.junit.BeforeClass;
 import org.junit.Test;
+import org.mockito.Mockito;
 
 import javax.inject.Singleton;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.concurrent.ScheduledExecutorService;
 
 public class DatastoreServiceIntegrationTest {
 
   private static ServiceLocator locator;
   private static DatastoreService datastoreService;
 
+  private static ScheduledExecutorService mockScheduledExecutorService;
+
   // BeforeClass because there's no reason to start/stop Elasticsearch for every test when
   // all our operations are read-only
   @BeforeClass
   public static void setUp() throws Exception {
+    mockScheduledExecutorService = Mockito.mock(ScheduledExecutorService.class);
     locator  = ServiceLocatorUtilities.bind(
       new io.jenkins.plugins.datastore.Binder(),
       new AbstractBinder() {
         @Override
         protected void configure() {
+          bind(mockScheduledExecutorService.getClass()).to(ScheduledExecutorService.class).in(Singleton.class);
           bind(MockConfigurationService.class).to(ConfigurationService.class).in(Singleton.class);
           bind(ElasticsearchDatastoreService.class).to(DatastoreService.class).in(Singleton.class);
           bind(HttpClientWikiService.class).to(WikiService.class).in(Singleton.class);

src/test/java/io/jenkins/plugins/services/MockConfigurationService.java

@@ -8,6 +8,9 @@ import org.slf4j.LoggerFactory;
 
 import java.io.File;
 
+/**
+ * <p>Mocked ConfigurationService</p>
+ */
 public class MockConfigurationService implements ConfigurationService {
 
   private final Logger logger = LoggerFactory.getLogger(MockConfigurationService.class);