feat: automatically derive the the dependent resource type if not specified

Signed-off-by: xstefank <xstefank122@gmail.com>

Author: xstefank

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/AbstractEventSourceHolderDependentResource.java

@@ -1,5 +1,6 @@
 package io.javaoperatorsdk.operator.processing.dependent;
 
+import java.lang.reflect.ParameterizedType;
 import java.util.Optional;
 
 import io.fabric8.kubernetes.api.model.HasMetadata;
@@ -23,13 +24,25 @@ public abstract class AbstractEventSourceHolderDependentResource<
   private boolean isCacheFillerEventSource;
   protected String eventSourceNameToUse;
 
+  @SuppressWarnings("unchecked")
+  protected AbstractEventSourceHolderDependentResource() {
+    this(null, null);
+  }
+
   protected AbstractEventSourceHolderDependentResource(Class<R> resourceType) {
     this(resourceType, null);
   }
 
+  @SuppressWarnings("unchecked")
   protected AbstractEventSourceHolderDependentResource(Class<R> resourceType, String name) {
     super(name);
-    this.resourceType = resourceType;
+    if (resourceType == null) {
+      this.resourceType =
+          (Class<R>)
+              ((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[0];
+    } else {
+      this.resourceType = resourceType;
+    }
   }
 
   /**

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/AbstractExternalDependentResource.java

@@ -21,6 +21,8 @@ public abstract class AbstractExternalDependentResource<
 
   private InformerEventSource<?, P> externalStateEventSource;
 
+  protected AbstractExternalDependentResource() {}
+
   @SuppressWarnings("unchecked")
   protected AbstractExternalDependentResource(Class<R> resourceType) {
     super(resourceType);

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/external/AbstractPollingDependentResource.java

@@ -16,6 +16,8 @@ public abstract class AbstractPollingDependentResource<R, P extends HasMetadata>
   public static final Duration DEFAULT_POLLING_PERIOD = Duration.ofMillis(5000);
   private Duration pollingPeriod;
 
+  protected AbstractPollingDependentResource() {}
+
   protected AbstractPollingDependentResource(Class<R> resourceType) {
     this(resourceType, DEFAULT_POLLING_PERIOD);
   }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/external/PerResourcePollingDependentResource.java

@@ -14,6 +14,8 @@ public abstract class PerResourcePollingDependentResource<R, P extends HasMetada
     extends AbstractPollingDependentResource<R, P>
     implements PerResourcePollingEventSource.ResourceFetcher<R, P> {
 
+  public PerResourcePollingDependentResource() {}
+
   public PerResourcePollingDependentResource(Class<R> resourceType) {
     super(resourceType);
   }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/kubernetes/CRUDKubernetesDependentResource.java

@@ -18,6 +18,8 @@ public abstract class CRUDKubernetesDependentResource<R extends HasMetadata, P e
     extends KubernetesDependentResource<R, P>
     implements Creator<R, P>, Updater<R, P>, GarbageCollected<P> {
 
+  public CRUDKubernetesDependentResource() {}
+
   public CRUDKubernetesDependentResource(Class<R> resourceType) {
     super(resourceType);
   }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/kubernetes/KubernetesDependentResource.java

@@ -41,6 +41,8 @@ public abstract class KubernetesDependentResource<R extends HasMetadata, P exten
   private KubernetesDependentResourceConfig<R> kubernetesDependentResourceConfig;
   private volatile Boolean useSSA;
 
+  public KubernetesDependentResource() {}
+
   public KubernetesDependentResource(Class<R> resourceType) {
     this(resourceType, null);
   }

sample-operators/mysql-schema/src/main/java/io/javaoperatorsdk/operator/sample/dependent/SchemaDependentResource.java

@@ -54,10 +54,6 @@ public class SchemaDependentResource
 
   private MySQLDbConfig dbConfig;
 
-  public SchemaDependentResource() {
-    super(Schema.class);
-  }
-
   @Override
   public Optional<ResourcePollerConfig> configuration() {
     return Optional.of(new ResourcePollerConfig(getPollingPeriod(), dbConfig));

sample-operators/mysql-schema/src/main/java/io/javaoperatorsdk/operator/sample/dependent/SecretDependentResource.java

@@ -27,10 +27,6 @@ public class SecretDependentResource extends KubernetesDependentResource<Secret,
   public static final String MYSQL_SECRET_USERNAME = "mysql.secret.user.name";
   public static final String MYSQL_SECRET_PASSWORD = "mysql.secret.user.password";
 
-  public SecretDependentResource() {
-    super(Secret.class);
-  }
-
   private static String encode(String value) {
     return Base64.getEncoder().encodeToString(value.getBytes());
   }

sample-operators/tomcat-operator/src/main/java/io/javaoperatorsdk/operator/sample/DeploymentDependentResource.java

@@ -14,10 +14,6 @@
 public class DeploymentDependentResource
     extends CRUDKubernetesDependentResource<Deployment, Tomcat> {
 
-  public DeploymentDependentResource() {
-    super(Deployment.class);
-  }
-
   private static String tomcatImage(Tomcat tomcat) {
     return "tomcat:" + tomcat.getSpec().getVersion();
   }

sample-operators/tomcat-operator/src/main/java/io/javaoperatorsdk/operator/sample/ServiceDependentResource.java

@@ -13,10 +13,6 @@
     informer = @Informer(labelSelector = "app.kubernetes.io/managed-by=tomcat-operator"))
 public class ServiceDependentResource extends CRUDKubernetesDependentResource<Service, Tomcat> {
 
-  public ServiceDependentResource() {
-    super(Service.class);
-  }
-
   @Override
   protected Service desired(Tomcat tomcat, Context<Tomcat> context) {
     final ObjectMeta tomcatMetadata = tomcat.getMetadata();