diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/BaseResource.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/BaseResource.java
index 10b218db..ecca1af9 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/BaseResource.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/BaseResource.java
@@ -27,6 +27,16 @@
 import org.apache.spark.k8s.operator.status.BaseState;
 import org.apache.spark.k8s.operator.status.BaseStatus;
 
+/**
+ * Base class for Spark Kubernetes Operator's custom resources like SparkApplication and
+ * SparkCluster.
+ *
+ * @param <S> The type of the state.
+ * @param <AS> The type of the attempt summary.
+ * @param <STATE> The type of the state.
+ * @param <SPEC> The type of the spec.
+ * @param <STATUS> The type of the status.
+ */
 public class BaseResource<
     S,
     AS extends BaseAttemptSummary,
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/Constants.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/Constants.java
index c300041a..2c074f11 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/Constants.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/Constants.java
@@ -19,6 +19,7 @@
 
 package org.apache.spark.k8s.operator;
 
+/** Constants used in the Spark Kubernetes Operator. */
 @SuppressWarnings("PMD.DataClass")
 public class Constants {
   public static final String API_GROUP = "spark.apache.org";
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplication.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplication.java
index 3717ee71..a95241d1 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplication.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplication.java
@@ -32,6 +32,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationStateSummary;
 import org.apache.spark.k8s.operator.status.ApplicationStatus;
 
+/** SparkApplication is the Custom Resource Definition (CRD) for a Spark application. */
 @JsonInclude(JsonInclude.Include.NON_NULL)
 @JsonDeserialize()
 @Group(Constants.API_GROUP)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplicationList.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplicationList.java
index 9da21e6b..db54f6bd 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplicationList.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkApplicationList.java
@@ -22,5 +22,6 @@
 import io.fabric8.kubernetes.api.model.DefaultKubernetesResourceList;
 import lombok.NoArgsConstructor;
 
+/** List of SparkApplications. */
 @NoArgsConstructor
 public class SparkApplicationList extends DefaultKubernetesResourceList<SparkApplication> {}
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkCluster.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkCluster.java
index 4f0c6898..2d0ed8d0 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkCluster.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkCluster.java
@@ -32,6 +32,7 @@
 import org.apache.spark.k8s.operator.status.ClusterStateSummary;
 import org.apache.spark.k8s.operator.status.ClusterStatus;
 
+/** SparkCluster is the Custom Resource Definition (CRD) for a Spark cluster. */
 @JsonInclude(JsonInclude.Include.NON_NULL)
 @JsonDeserialize()
 @Group(Constants.API_GROUP)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkClusterList.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkClusterList.java
index 035b78c1..78883f50 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkClusterList.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/SparkClusterList.java
@@ -22,5 +22,6 @@
 import io.fabric8.kubernetes.api.model.DefaultKubernetesResourceList;
 import lombok.NoArgsConstructor;
 
+/** List of SparkClusters. */
 @NoArgsConstructor
 public class SparkClusterList extends DefaultKubernetesResourceList<SparkCluster> {}
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationSpec.java
index 9d7722f5..f8fd531c 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationSpec.java
@@ -31,6 +31,7 @@
 import lombok.EqualsAndHashCode;
 import lombok.NoArgsConstructor;
 
+/** Spec for a Spark application. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTimeoutConfig.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTimeoutConfig.java
index 2bf96326..b2bbcc7c 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTimeoutConfig.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTimeoutConfig.java
@@ -26,6 +26,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Application timeout configuration. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTolerations.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTolerations.java
index f1fadf79..8e2bef0d 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTolerations.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ApplicationTolerations.java
@@ -26,6 +26,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Toleration settings for a Spark application. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseApplicationTemplateSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseApplicationTemplateSpec.java
index 7fd7e3a5..35c72269 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseApplicationTemplateSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseApplicationTemplateSpec.java
@@ -27,6 +27,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Base class for application template specs for driver and executors. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseSpec.java
index 3522ad34..bfef359f 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/BaseSpec.java
@@ -28,6 +28,7 @@
 
 import org.apache.spark.k8s.operator.diff.Diffable;
 
+/** Base spec for all custom resources. */
 @Data
 @JsonInclude(JsonInclude.Include.NON_NULL)
 @JsonIgnoreProperties(ignoreUnknown = true)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterSpec.java
index 408f8d62..12b06448 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterSpec.java
@@ -28,6 +28,7 @@
 import lombok.EqualsAndHashCode;
 import lombok.NoArgsConstructor;
 
+/** Spec for a Spark cluster. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterTolerations.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterTolerations.java
index d7e546bf..e59cd24e 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterTolerations.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ClusterTolerations.java
@@ -25,6 +25,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Toleration settings for a Spark cluster. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ConfigMapSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ConfigMapSpec.java
index 8cce3fde..bdf00a14 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ConfigMapSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/ConfigMapSpec.java
@@ -28,6 +28,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Spec for a ConfigMap. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/DriverServiceIngressSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/DriverServiceIngressSpec.java
index 9712a652..5ddccf1d 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/DriverServiceIngressSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/DriverServiceIngressSpec.java
@@ -28,6 +28,7 @@
 import lombok.Builder;
 import lombok.Data;
 
+/** Spec for a driver service ingress. */
 @Data
 @Builder
 @JsonInclude(JsonInclude.Include.NON_NULL)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/MasterSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/MasterSpec.java
index c04a2be9..a459a9ab 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/MasterSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/MasterSpec.java
@@ -28,6 +28,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Spec for a Spark master. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RestartConfig.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RestartConfig.java
index 2c19cd23..f724b43e 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RestartConfig.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RestartConfig.java
@@ -26,6 +26,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Restart configuration for a Spark application. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RuntimeVersions.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RuntimeVersions.java
index 819cca8c..11abbe90 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RuntimeVersions.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/RuntimeVersions.java
@@ -27,6 +27,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Runtime versions for a Spark application or cluster. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerInstanceConfig.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerInstanceConfig.java
index 5adca3ec..914ccca6 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerInstanceConfig.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerInstanceConfig.java
@@ -25,6 +25,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Config tolerations of worker instances for the cluster. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerSpec.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerSpec.java
index 78b86e3c..7094195b 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerSpec.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/spec/WorkerSpec.java
@@ -29,6 +29,7 @@
 import lombok.Data;
 import lombok.NoArgsConstructor;
 
+/** Spec for a Spark worker. */
 @Data
 @NoArgsConstructor
 @AllArgsConstructor
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationAttemptSummary.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationAttemptSummary.java
index a9019358..2d3c6a70 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationAttemptSummary.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationAttemptSummary.java
@@ -27,6 +27,7 @@
 import lombok.Getter;
 import lombok.ToString;
 
+/** Summary of a Spark application attempt. */
 @Getter
 @EqualsAndHashCode(callSuper = true)
 @ToString(callSuper = true)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationState.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationState.java
index 33614f83..b4dcdfb2 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationState.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationState.java
@@ -32,6 +32,7 @@
 import lombok.Setter;
 import lombok.ToString;
 
+/** Represents the state of a Spark application. */
 @ToString(callSuper = true)
 @EqualsAndHashCode(callSuper = true)
 @JsonInclude(JsonInclude.Include.NON_NULL)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationStatus.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationStatus.java
index 28134409..87bc31f2 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationStatus.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ApplicationStatus.java
@@ -34,6 +34,7 @@
 import org.apache.spark.k8s.operator.spec.RestartConfig;
 import org.apache.spark.k8s.operator.spec.RestartPolicy;
 
+/** Represents the status of a Spark application. */
 @EqualsAndHashCode(callSuper = true)
 @ToString(callSuper = true)
 @JsonInclude(JsonInclude.Include.NON_NULL)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/AttemptInfo.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/AttemptInfo.java
index 84c8b766..1222820e 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/AttemptInfo.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/AttemptInfo.java
@@ -28,6 +28,7 @@
 import lombok.NoArgsConstructor;
 import lombok.ToString;
 
+/** Information about an attempt. */
 @NoArgsConstructor
 @AllArgsConstructor
 @Builder
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseAttemptSummary.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseAttemptSummary.java
index 8078529e..ad7673ee 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseAttemptSummary.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseAttemptSummary.java
@@ -26,6 +26,7 @@
 import lombok.RequiredArgsConstructor;
 import lombok.ToString;
 
+/** Base class for attempt summaries. */
 @EqualsAndHashCode
 @ToString
 @Getter
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseState.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseState.java
index e73cd355..82d8623d 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseState.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseState.java
@@ -26,6 +26,11 @@
 import lombok.AllArgsConstructor;
 import lombok.Data;
 
+/**
+ * Base class for state information.
+ *
+ * @param <T> The type of the current state summary.
+ */
 @Data
 @AllArgsConstructor
 @JsonInclude(JsonInclude.Include.NON_NULL)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseStatus.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseStatus.java
index ab1d6425..455e76ff 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseStatus.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/BaseStatus.java
@@ -29,6 +29,13 @@
 import lombok.Getter;
 import lombok.ToString;
 
+/**
+ * Base class for status information.
+ *
+ * @param <S> The type of the state summary.
+ * @param <STATE> The type of the state.
+ * @param <AS> The type of the attempt summary.
+ */
 @ToString
 @EqualsAndHashCode
 @JsonInclude(JsonInclude.Include.NON_NULL)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterAttemptSummary.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterAttemptSummary.java
index e0fb7cd4..4a79c88d 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterAttemptSummary.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterAttemptSummary.java
@@ -27,6 +27,7 @@
 import lombok.Getter;
 import lombok.ToString;
 
+/** Summary of a Spark cluster attempt. */
 @Getter
 @EqualsAndHashCode(callSuper = true)
 @ToString(callSuper = true)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterState.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterState.java
index 2d6a832a..1ccd8e6b 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterState.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterState.java
@@ -29,6 +29,7 @@
 import lombok.EqualsAndHashCode;
 import lombok.ToString;
 
+/** Represents the state of a Spark cluster. */
 @ToString(callSuper = true)
 @EqualsAndHashCode(callSuper = true)
 @JsonInclude(JsonInclude.Include.NON_NULL)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterStatus.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterStatus.java
index 73c92077..5cc97b3f 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterStatus.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/status/ClusterStatus.java
@@ -27,6 +27,7 @@
 import lombok.EqualsAndHashCode;
 import lombok.ToString;
 
+/** Represents the status of a Spark cluster. */
 @EqualsAndHashCode(callSuper = true)
 @ToString(callSuper = true)
 @JsonInclude(JsonInclude.Include.NON_NULL)
diff --git a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/utils/ModelUtils.java b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/utils/ModelUtils.java
index e9ed22e7..5351594f 100644
--- a/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/utils/ModelUtils.java
+++ b/spark-operator-api/src/main/java/org/apache/spark/k8s/operator/utils/ModelUtils.java
@@ -38,6 +38,7 @@
 import org.apache.spark.k8s.operator.SparkApplication;
 import org.apache.spark.k8s.operator.spec.ApplicationSpec;
 
+/** Utility class for Kubernetes model operations. */
 public final class ModelUtils {
 
   public static final ObjectMapper objectMapper = new ObjectMapper();
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/SparkOperator.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/SparkOperator.java
index 00619d7a..4eaf2106 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/SparkOperator.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/SparkOperator.java
@@ -57,7 +57,7 @@
 /**
  * Entry point for Spark Operator. Bootstrap the operator app by starting watch and reconciler for
  * SparkApps, starting watch for hot property loading, if enabled, and starting metrics server with
- * sentinel monitor if enabled
+ * sentinel monitor if enabled.
  */
 @Slf4j
 public class SparkOperator {
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/client/KubernetesClientFactory.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/client/KubernetesClientFactory.java
index 766c1c54..5e103dfc 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/client/KubernetesClientFactory.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/client/KubernetesClientFactory.java
@@ -27,7 +27,7 @@
 import okhttp3.Interceptor;
 import okhttp3.OkHttpClient;
 
-/** Build Kubernetes Client with metrics configured */
+/** Factory for building Kubernetes clients with metrics configured. */
 public final class KubernetesClientFactory {
 
   private KubernetesClientFactory() {}
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/config/ConfigOption.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/config/ConfigOption.java
index e0726c4f..4f7b03de 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/config/ConfigOption.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/config/ConfigOption.java
@@ -31,7 +31,11 @@
 
 import org.apache.spark.k8s.operator.utils.ModelUtils;
 
-/** Config options for Spark Operator. Supports primitive and serialized JSON */
+/**
+ * Config options for Spark Operator. Supports primitive and serialized JSON.
+ *
+ * @param <T> The type of the config option's value.
+ */
 @RequiredArgsConstructor
 @AllArgsConstructor
 @EqualsAndHashCode
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/context/BaseContext.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/context/BaseContext.java
index 98bddb5a..82b23478 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/context/BaseContext.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/context/BaseContext.java
@@ -23,6 +23,11 @@
 
 import org.apache.spark.k8s.operator.BaseResource;
 
+/**
+ * Base class for context objects.
+ *
+ * @param <CR> The type of the custom resource.
+ */
 public abstract class BaseContext<CR extends BaseResource<?, ?, ?, ?, ?>> {
   public abstract CR getResource();
 
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/listeners/BaseStatusListener.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/listeners/BaseStatusListener.java
index 17076b8b..f3d12c53 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/listeners/BaseStatusListener.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/listeners/BaseStatusListener.java
@@ -21,7 +21,12 @@
 import org.apache.spark.k8s.operator.BaseResource;
 import org.apache.spark.k8s.operator.status.BaseStatus;
 
-/** Custom listeners, if added, would be listening to resource status change */
+/**
+ * Custom listeners, if added, would be listening to resource status change.
+ *
+ * @param <STATUS> The type of the status.
+ * @param <CR> The type of the custom resource.
+ */
 public abstract class BaseStatusListener<
     STATUS extends BaseStatus<?, ?, ?>, CR extends BaseResource<?, ?, ?, ?, STATUS>> {
   public abstract void listenStatus(CR resource, STATUS prevStatus, STATUS updatedStatus);
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/JVMMetricSet.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/JVMMetricSet.java
index a87d5bda..8a4a27ae 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/JVMMetricSet.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/JVMMetricSet.java
@@ -31,6 +31,7 @@
 import com.codahale.metrics.jvm.MemoryUsageGaugeSet;
 import com.codahale.metrics.jvm.ThreadStatesGaugeSet;
 
+/** A MetricSet for JVM metrics. */
 public class JVMMetricSet implements MetricSet {
 
   /** Refer codahale FileDescriptorRatioGauge for the definition */
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsService.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsService.java
index c97818ea..ea5e6bdc 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsService.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsService.java
@@ -28,7 +28,7 @@
 import com.sun.net.httpserver.HttpServer;
 import lombok.extern.slf4j.Slf4j;
 
-/** Start Http service at endpoint /prometheus, exposing operator metrics */
+/** Start Http service at endpoint /prometheus, exposing operator metrics. */
 @Slf4j
 public class MetricsService {
   HttpServer server;
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystem.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystem.java
index 4194144c..1b212dc0 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystem.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystem.java
@@ -36,6 +36,7 @@
 import org.apache.spark.metrics.sink.Sink;
 import org.apache.spark.metrics.source.Source;
 
+/** Manages the metrics system for the Spark Operator. */
 @Slf4j
 public class MetricsSystem {
   private final AtomicBoolean running = new AtomicBoolean(false);
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystemFactory.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystemFactory.java
index f93c1cca..0eb1de9d 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystemFactory.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/MetricsSystemFactory.java
@@ -28,7 +28,7 @@
 
 import org.apache.spark.k8s.operator.config.SparkOperatorConfManager;
 
-/** Factory for MetricsSystem */
+/** Factory for MetricsSystem. */
 public final class MetricsSystemFactory {
   public static final String METRIC_PREFIX = "spark.metrics.conf.operator.";
   public static final String SINK = "sink.";
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/PrometheusPullModelHandler.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/PrometheusPullModelHandler.java
index fc935c5a..d5a72a8c 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/PrometheusPullModelHandler.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/PrometheusPullModelHandler.java
@@ -37,7 +37,7 @@
 
 import org.apache.spark.metrics.sink.PrometheusServlet;
 
-/** Serves as simple Prometheus sink (pull model), presenting metrics snapshot as HttpHandler */
+/** Serves as simple Prometheus sink (pull model), presenting metrics snapshot as HttpHandler. */
 @Slf4j
 public class PrometheusPullModelHandler extends PrometheusServlet implements HttpHandler {
   private static final String EMPTY_RECORD_VALUE = "[]";
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/healthcheck/SentinelManager.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/healthcheck/SentinelManager.java
index 05255555..ec5e32e6 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/healthcheck/SentinelManager.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/healthcheck/SentinelManager.java
@@ -43,7 +43,7 @@
 import org.apache.spark.k8s.operator.utils.Utils;
 
 /**
- * Sentinel manager monitors dedicated sentinel resources to make sure the operator is healthy
+ * Sentinel manager monitors dedicated sentinel resources to make sure the operator is healthy.
  *
  * @param <CR> custom resource type
  */
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/KubernetesMetricsInterceptor.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/KubernetesMetricsInterceptor.java
index 58240790..aab1c0e8 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/KubernetesMetricsInterceptor.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/KubernetesMetricsInterceptor.java
@@ -40,6 +40,7 @@
 
 import org.apache.spark.metrics.source.Source;
 
+/** Interceptor for Kubernetes client to collect metrics. */
 @Slf4j
 public class KubernetesMetricsInterceptor implements Interceptor, Source {
   final MetricRegistry metricRegistry;
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJosdkMetrics.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJosdkMetrics.java
index 530848e8..86a34ff5 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJosdkMetrics.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJosdkMetrics.java
@@ -48,6 +48,7 @@
 import org.apache.spark.util.Clock;
 import org.apache.spark.util.SystemClock;
 
+/** Metrics for the Java Operator SDK. */
 @Slf4j
 public class OperatorJosdkMetrics implements Source, Metrics {
   public static final String FINISHED = "finished";
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJvmSource.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJvmSource.java
index 8cf7df07..ccbb4785 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJvmSource.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/metrics/source/OperatorJvmSource.java
@@ -24,6 +24,7 @@
 import org.apache.spark.k8s.operator.metrics.JVMMetricSet;
 import org.apache.spark.metrics.source.Source;
 
+/** Source for JVM metrics. */
 public class OperatorJvmSource implements Source {
   @Override
   public String sourceName() {
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/HealthProbe.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/HealthProbe.java
index 4df568aa..5b33a9ed 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/HealthProbe.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/HealthProbe.java
@@ -43,6 +43,7 @@
 
 import org.apache.spark.k8s.operator.metrics.healthcheck.SentinelManager;
 
+/** Health probe for the operator. */
 @Getter
 @Slf4j
 @RequiredArgsConstructor
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ProbeService.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ProbeService.java
index d562e7b9..2446be63 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ProbeService.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ProbeService.java
@@ -33,6 +33,7 @@
 
 import org.apache.spark.k8s.operator.metrics.healthcheck.SentinelManager;
 
+/** Service for health and readiness probes. */
 @Slf4j
 public class ProbeService {
   public static final String HEALTHZ = "/healthz";
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ReadinessProbe.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ReadinessProbe.java
index 19c0cdf4..d66d9bf4 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ReadinessProbe.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/probe/ReadinessProbe.java
@@ -32,6 +32,7 @@
 import io.javaoperatorsdk.operator.Operator;
 import lombok.extern.slf4j.Slf4j;
 
+/** Readiness probe for the operator. */
 @Slf4j
 public class ReadinessProbe implements HttpHandler {
   private final List<Operator> operators;
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkAppResourceSpecFactory.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkAppResourceSpecFactory.java
index 35871fa1..98ba0fbf 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkAppResourceSpecFactory.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkAppResourceSpecFactory.java
@@ -44,6 +44,7 @@
 import org.apache.spark.k8s.operator.decorators.DriverDecorator;
 import org.apache.spark.k8s.operator.utils.ModelUtils;
 
+/** Factory for creating SparkAppResourceSpec objects. */
 @Slf4j
 public final class SparkAppResourceSpecFactory {
 
@@ -74,7 +75,6 @@ private static Map<String, String> overrideDependencyConf(final SparkApplication
     if (app.getSpec().getSparkConf().containsKey("spark.app.name")) {
       confOverrides.put("spark.app.name", app.getMetadata().getName());
     }
-    // FIXME: avoid this file flushing
     confOverrides.putAll(getOrCreateLocalFileForDriverSpec(app, confOverrides));
     confOverrides.putAll(getOrCreateLocalFileForExecutorSpec(app, confOverrides));
     return confOverrides;
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkClusterResourceSpecFactory.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkClusterResourceSpecFactory.java
index 8518019f..45d63722 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkClusterResourceSpecFactory.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/SparkClusterResourceSpecFactory.java
@@ -29,6 +29,7 @@
 import org.apache.spark.k8s.operator.SparkClusterSubmissionWorker;
 import org.apache.spark.k8s.operator.decorators.ClusterDecorator;
 
+/** Factory for creating SparkClusterResourceSpec objects. */
 @Slf4j
 public final class SparkClusterResourceSpecFactory {
 
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverReadyObserver.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverReadyObserver.java
index 92f9d7c9..7a506f12 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverReadyObserver.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverReadyObserver.java
@@ -31,7 +31,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationStatus;
 import org.apache.spark.k8s.operator.utils.PodUtils;
 
-/** Observes whether driver is ready */
+/** Observes whether driver is ready. */
 public class AppDriverReadyObserver extends BaseAppDriverObserver {
   @Override
   public Optional<ApplicationState> observe(
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverStartObserver.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverStartObserver.java
index 656c81db..66c92576 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverStartObserver.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverStartObserver.java
@@ -31,6 +31,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationStatus;
 import org.apache.spark.k8s.operator.utils.PodUtils;
 
+/** Observes whether the driver pod has started. */
 public class AppDriverStartObserver extends BaseAppDriverObserver {
   @Override
   public Optional<ApplicationState> observe(
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverTimeoutObserver.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverTimeoutObserver.java
index b971fe9f..6b26c028 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverTimeoutObserver.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/AppDriverTimeoutObserver.java
@@ -31,7 +31,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationStatus;
 import org.apache.spark.k8s.operator.utils.SparkAppStatusUtils;
 
-/** Observes driver status and time-out as configured in app spec */
+/** Observes driver status and time-out as configured in app spec. */
 public class AppDriverTimeoutObserver extends BaseAppDriverObserver {
 
   /**
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseAppDriverObserver.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseAppDriverObserver.java
index 6548cce1..dd8ba643 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseAppDriverObserver.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseAppDriverObserver.java
@@ -40,7 +40,7 @@
 import org.apache.spark.k8s.operator.utils.PodPhase;
 import org.apache.spark.k8s.operator.utils.PodUtils;
 
-/** Observes driver pod status and update Application status as needed */
+/** Observes driver pod status and update Application status as needed. */
 @Slf4j
 public abstract class BaseAppDriverObserver
     extends BaseSecondaryResourceObserver<
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseSecondaryResourceObserver.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseSecondaryResourceObserver.java
index 3c91ead6..1bb3a963 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseSecondaryResourceObserver.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/observers/BaseSecondaryResourceObserver.java
@@ -31,6 +31,13 @@
 /**
  * Observe given secondary resource, return state to be updated if applicable. These observers only
  * observe secondary resource status and update the status of owner, SparkApplication, if needed.
+ *
+ * @param <S> The type of the state summary.
+ * @param <AS> The type of the attempt summary.
+ * @param <STATE> The type of the state.
+ * @param <SPEC> The type of the spec.
+ * @param <STATUS> The type of the status.
+ * @param <SR> The type of the secondary resource.
  */
 public abstract class BaseSecondaryResourceObserver<
     S,
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppCleanUpStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppCleanUpStep.java
index f75967a1..3f01134b 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppCleanUpStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppCleanUpStep.java
@@ -48,7 +48,7 @@
 
 /**
  * Cleanup all secondary resources when application is deleted, or at the end of each attempt.
- * Update Application status to indicate whether another attempt would be made
+ * Update Application status to indicate whether another attempt would be made.
  */
 @AllArgsConstructor
 @NoArgsConstructor
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppInitStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppInitStep.java
index 583d93b9..1e9f2cf7 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppInitStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppInitStep.java
@@ -44,7 +44,7 @@
 import org.apache.spark.k8s.operator.utils.ReconcilerUtils;
 import org.apache.spark.k8s.operator.utils.SparkAppStatusRecorder;
 
-/** Request all driver and its resources when starting an attempt */
+/** Request all driver and its resources when starting an attempt. */
 @Slf4j
 public class AppInitStep extends AppReconcileStep {
   @Override
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppReconcileStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppReconcileStep.java
index 91542ce3..6c414d46 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppReconcileStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppReconcileStep.java
@@ -37,7 +37,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationStatus;
 import org.apache.spark.k8s.operator.utils.SparkAppStatusRecorder;
 
-/** Basic reconcile step for application */
+/** Basic reconcile step for application. */
 public abstract class AppReconcileStep {
   public abstract ReconcileProgress reconcile(
       SparkAppContext context, SparkAppStatusRecorder statusRecorder);
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppResourceObserveStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppResourceObserveStep.java
index 0db6dfdf..83333f41 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppResourceObserveStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppResourceObserveStep.java
@@ -28,7 +28,7 @@
 import org.apache.spark.k8s.operator.reconciler.observers.BaseAppDriverObserver;
 import org.apache.spark.k8s.operator.utils.SparkAppStatusRecorder;
 
-/** Observes secondary resource and update app status if needed */
+/** Observes secondary resource and update app status if needed. */
 @RequiredArgsConstructor
 public class AppResourceObserveStep extends AppReconcileStep {
 
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppRunningStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppRunningStep.java
index 774cf616..524c1cf3 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppRunningStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppRunningStep.java
@@ -36,7 +36,7 @@
 import org.apache.spark.k8s.operator.utils.PodUtils;
 import org.apache.spark.k8s.operator.utils.SparkAppStatusRecorder;
 
-/** Observe whether app acquires enough executors as configured in spec */
+/** Observe whether app acquires enough executors as configured in spec. */
 public class AppRunningStep extends AppReconcileStep {
   @Override
   public ReconcileProgress reconcile(
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppUnknownStateStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppUnknownStateStep.java
index 715c235a..ef113749 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppUnknownStateStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/AppUnknownStateStep.java
@@ -30,7 +30,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationStateSummary;
 import org.apache.spark.k8s.operator.utils.SparkAppStatusRecorder;
 
-/** Abnormal state handler */
+/** Abnormal state handler. */
 public class AppUnknownStateStep extends AppReconcileStep {
   @Override
   public ReconcileProgress reconcile(
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterInitStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterInitStep.java
index 29c8cd0c..db2fc3df 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterInitStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterInitStep.java
@@ -40,7 +40,7 @@
 import org.apache.spark.k8s.operator.status.ClusterStatus;
 import org.apache.spark.k8s.operator.utils.SparkClusterStatusRecorder;
 
-/** Request cluster master and its resources when starting an attempt */
+/** Request cluster master and its resources when starting an attempt. */
 @Slf4j
 public class ClusterInitStep extends ClusterReconcileStep {
   @Override
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterReconcileStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterReconcileStep.java
index 444c20f0..0a3199c0 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterReconcileStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterReconcileStep.java
@@ -27,7 +27,7 @@
 import org.apache.spark.k8s.operator.status.ClusterStatus;
 import org.apache.spark.k8s.operator.utils.SparkClusterStatusRecorder;
 
-/** Basic reconcile step for cluster */
+/** Basic reconcile step for cluster. */
 public abstract class ClusterReconcileStep {
   public abstract ReconcileProgress reconcile(
       SparkClusterContext context, SparkClusterStatusRecorder statusRecorder);
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterUnknownStateStep.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterUnknownStateStep.java
index 87eb8eb0..6e70cd82 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterUnknownStateStep.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/reconciler/reconcilesteps/ClusterUnknownStateStep.java
@@ -26,7 +26,7 @@
 import org.apache.spark.k8s.operator.status.ClusterStateSummary;
 import org.apache.spark.k8s.operator.utils.SparkClusterStatusRecorder;
 
-/** Abnormal state handler */
+/** Abnormal state handler for clusters. */
 public class ClusterUnknownStateStep extends ClusterReconcileStep {
   @Override
   public ReconcileProgress reconcile(
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ClassLoadingUtils.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ClassLoadingUtils.java
index 8d49fb40..f6e98c04 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ClassLoadingUtils.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ClassLoadingUtils.java
@@ -29,6 +29,7 @@
 
 import org.apache.spark.k8s.operator.listeners.BaseStatusListener;
 
+/** Utility class for loading classes. */
 @Slf4j
 public final class ClassLoadingUtils {
 
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/LoggingUtils.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/LoggingUtils.java
index 1958edb6..bbe30f0b 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/LoggingUtils.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/LoggingUtils.java
@@ -28,6 +28,7 @@
 import org.apache.spark.k8s.operator.SparkApplication;
 import org.apache.spark.k8s.operator.status.ApplicationAttemptSummary;
 
+/** Utility class for logging. */
 public class LoggingUtils {
   public static final class TrackedMDC {
     public static final String AppAttemptIdKey = "resource.app.attemptId";
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/PodUtils.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/PodUtils.java
index 65893590..81a4cf32 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/PodUtils.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/PodUtils.java
@@ -28,6 +28,7 @@
 
 import org.apache.spark.k8s.operator.spec.ApplicationSpec;
 
+/** Utility class for Pod operations. */
 public final class PodUtils {
 
   public static final String POD_READY_CONDITION_TYPE = "ready";
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ReconcilerUtils.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ReconcilerUtils.java
index 2d7bd282..3a901f03 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ReconcilerUtils.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/ReconcilerUtils.java
@@ -45,6 +45,7 @@
 import org.apache.spark.k8s.operator.BaseResource;
 import org.apache.spark.k8s.operator.reconciler.ReconcileProgress;
 
+/** Utility class for reconciler operations. */
 @Slf4j
 public final class ReconcilerUtils {
 
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusRecorder.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusRecorder.java
index 4ca31909..b03d6e3d 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusRecorder.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusRecorder.java
@@ -27,6 +27,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationState;
 import org.apache.spark.k8s.operator.status.ApplicationStatus;
 
+/** Records the status of a Spark application. */
 public class SparkAppStatusRecorder
     extends StatusRecorder<ApplicationStatus, SparkApplication, SparkAppStatusListener> {
   public SparkAppStatusRecorder(List<SparkAppStatusListener> statusListeners) {
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusUtils.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusUtils.java
index 56b3e076..ecbe3e20 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusUtils.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkAppStatusUtils.java
@@ -24,7 +24,7 @@
 import org.apache.spark.k8s.operator.status.ApplicationState;
 import org.apache.spark.k8s.operator.status.ApplicationStateSummary;
 
-/** Handy utils for create and manage Application Status */
+/** Handy utils for create and manage Application Status. */
 public final class SparkAppStatusUtils {
 
   private SparkAppStatusUtils() {}
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkClusterStatusRecorder.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkClusterStatusRecorder.java
index 2495d052..82808c34 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkClusterStatusRecorder.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkClusterStatusRecorder.java
@@ -27,6 +27,7 @@
 import org.apache.spark.k8s.operator.status.ClusterState;
 import org.apache.spark.k8s.operator.status.ClusterStatus;
 
+/** Records the status of a Spark cluster. */
 public class SparkClusterStatusRecorder
     extends StatusRecorder<ClusterStatus, SparkCluster, SparkClusterStatusListener> {
   public SparkClusterStatusRecorder(List<SparkClusterStatusListener> statusListeners) {
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkExceptionUtils.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkExceptionUtils.java
index 8221b4bb..dabac325 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkExceptionUtils.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/SparkExceptionUtils.java
@@ -25,6 +25,7 @@
 import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.lang3.exception.ExceptionUtils;
 
+/** Utility class for Spark exceptions. */
 public final class SparkExceptionUtils {
 
   private SparkExceptionUtils() {}
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/StatusRecorder.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/StatusRecorder.java
index 214f88bf..7a4f114c 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/StatusRecorder.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/StatusRecorder.java
@@ -42,6 +42,10 @@
 /**
  * Enables additional (extendable) observers for Spark App status. Cache and version locking might
  * be removed in future version as batch app does not expect spec change after submitted.
+ *
+ * @param <STATUS> The type of the status.
+ * @param <CR> The type of the custom resource.
+ * @param <LISTENER> The type of the status listener.
  */
 @Slf4j
 public class StatusRecorder<
diff --git a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/Utils.java b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/Utils.java
index 28c1cf6b..c6b2b7fe 100644
--- a/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/Utils.java
+++ b/spark-operator/src/main/java/org/apache/spark/k8s/operator/utils/Utils.java
@@ -46,6 +46,7 @@
 import org.apache.spark.k8s.operator.listeners.SparkAppStatusListener;
 import org.apache.spark.k8s.operator.listeners.SparkClusterStatusListener;
 
+/** Utility class for common operations. */
 public final class Utils {
 
   private Utils() {}
diff --git a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppDriverConf.java b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppDriverConf.java
index 30ed0418..cbe3f43e 100644
--- a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppDriverConf.java
+++ b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppDriverConf.java
@@ -28,6 +28,7 @@
 import org.apache.spark.deploy.k8s.submit.KubernetesClientUtils;
 import org.apache.spark.deploy.k8s.submit.MainAppResource;
 
+/** Spark application driver configuration. */
 public final class SparkAppDriverConf extends KubernetesDriverConf {
   private SparkAppDriverConf(
       SparkConf sparkConf,
diff --git a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppResourceSpec.java b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppResourceSpec.java
index 8fe2bba8..e21647dd 100644
--- a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppResourceSpec.java
+++ b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppResourceSpec.java
@@ -57,7 +57,7 @@
  *   <li>Converts scala types to Java for easier reference from operator
  * </ul>
  *
- * <p>This is not thread safe and not expected to be shared among reconciler threads
+ * <p>This is not thread safe and not expected to be shared among reconciler threads.
  */
 public class SparkAppResourceSpec {
   @Getter private final Pod configuredPod;
diff --git a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppSubmissionWorker.java b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppSubmissionWorker.java
index d204c5d7..acccb8cd 100644
--- a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppSubmissionWorker.java
+++ b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkAppSubmissionWorker.java
@@ -44,7 +44,7 @@
 
 /**
  * Similar to org.apache.spark.deploy.k8s.submit.KubernetesClientApplication. This reads args from
- * SparkApplication instead of starting separate spark-submit process
+ * SparkApplication instead of starting separate spark-submit process.
  */
 public class SparkAppSubmissionWorker {
   // Default length limit for generated app id. Generated id is used as resource-prefix when
diff --git a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterResourceSpec.java b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterResourceSpec.java
index f35cd68f..834739c3 100644
--- a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterResourceSpec.java
+++ b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterResourceSpec.java
@@ -46,7 +46,7 @@
 import org.apache.spark.k8s.operator.spec.MasterSpec;
 import org.apache.spark.k8s.operator.spec.WorkerSpec;
 
-/** Spark Cluster Resource Spec: Master Service, Master StatefulSet, Worker StatefulSet */
+/** Spark Cluster Resource Spec: Master Service, Master StatefulSet, Worker StatefulSet. */
 public class SparkClusterResourceSpec {
   @Getter private final Service masterService;
   @Getter private final Service workerService;
diff --git a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterSubmissionWorker.java b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterSubmissionWorker.java
index 5cf77cfc..0193f623 100644
--- a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterSubmissionWorker.java
+++ b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/SparkClusterSubmissionWorker.java
@@ -25,6 +25,7 @@
 
 import org.apache.spark.SparkConf;
 
+/** Worker for submitting Spark clusters. */
 public class SparkClusterSubmissionWorker {
   public SparkClusterResourceSpec getResourceSpec(
       SparkCluster cluster, Map<String, String> confOverrides) {
diff --git a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/ConfigMapSpecUtils.java b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/ConfigMapSpecUtils.java
index fed1d1b6..8c01ef29 100644
--- a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/ConfigMapSpecUtils.java
+++ b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/ConfigMapSpecUtils.java
@@ -28,6 +28,7 @@
 
 import org.apache.spark.k8s.operator.spec.ConfigMapSpec;
 
+/** Utility class for ConfigMap specifications. */
 public final class ConfigMapSpecUtils {
   private ConfigMapSpecUtils() {}
 
diff --git a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/DriverServiceIngressUtils.java b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/DriverServiceIngressUtils.java
index 48d16c98..b794b963 100644
--- a/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/DriverServiceIngressUtils.java
+++ b/spark-submission-worker/src/main/java/org/apache/spark/k8s/operator/utils/DriverServiceIngressUtils.java
@@ -35,6 +35,7 @@
 
 import org.apache.spark.k8s.operator.spec.DriverServiceIngressSpec;
 
+/** Utility class for driver service ingress. */
 public final class DriverServiceIngressUtils {
   private DriverServiceIngressUtils() {}