Javadocs added

Author: inv-jishnu

data-loader/cli/src/main/java/com/scalar/db/dataloader/cli/command/dataexport/ExportCommand.java

@@ -132,6 +132,21 @@ private void validateOutputDirectory() throws DirectoryValidationException {
     }
   }
 
+  /**
+   * Creates a {@link TableMetadataService} instance based on the specified {@link ScalarDbMode} and
+   * ScalarDB configuration file.
+   *
+   * <p>If the mode is {@code TRANSACTION}, this method initializes a {@link TransactionFactory} and
+   * uses its transaction admin to create a {@link TableMetadataTransactionService}. Otherwise, it
+   * initializes a {@link StorageFactory} and creates a {@link TableMetadataStorageService} using
+   * its storage admin.
+   *
+   * @param scalarDbMode the mode ScalarDB is running in (either {@code STORAGE} or {@code
+   *     TRANSACTION})
+   * @param scalarDbPropertiesFilePath the path to the ScalarDB properties file
+   * @return an appropriate {@link TableMetadataService} based on the mode
+   * @throws IOException if reading the ScalarDB properties file fails
+   */
   private TableMetadataService createTableMetadataService(
       ScalarDbMode scalarDbMode, String scalarDbPropertiesFilePath) throws IOException {
     if (scalarDbMode.equals(ScalarDbMode.TRANSACTION)) {

data-loader/core/src/main/java/com/scalar/db/dataloader/core/dataexport/CsvExportManager.java

@@ -13,13 +13,35 @@
 import java.util.List;
 
 public class CsvExportManager extends ExportManager {
+  /**
+   * Constructs a {@code CsvExportManager} for exporting data using a {@link DistributedStorage}
+   * instance.
+   *
+   * <p>This constructor is used when exporting data in non-transactional (storage) mode.
+   *
+   * @param distributedStorage the {@link DistributedStorage} used to read data directly from
+   *     storage
+   * @param dao the {@link ScalarDbDao} used to interact with ScalarDB for exporting data
+   * @param producerTaskFactory the factory used to create producer tasks for generating
+   *     CSV-formatted output
+   */
   public CsvExportManager(
       DistributedStorage distributedStorage,
       ScalarDbDao dao,
       ProducerTaskFactory producerTaskFactory) {
     super(distributedStorage, dao, producerTaskFactory);
   }
 
+  /**
+   * Constructs a {@code CsvExportManager} for exporting data using a {@link
+   * DistributedTransactionManager}.
+   *
+   * @param distributedTransactionManager the transaction manager used to read data with
+   *     transactional guarantees
+   * @param dao the {@link ScalarDbDao} used to interact with ScalarDB for exporting data
+   * @param producerTaskFactory the factory used to create producer tasks for generating
+   *     CSV-formatted output
+   */
   public CsvExportManager(
       DistributedTransactionManager distributedTransactionManager,
       ScalarDbDao dao,

data-loader/core/src/main/java/com/scalar/db/dataloader/core/dataexport/ExportManager.java

@@ -42,6 +42,15 @@ public abstract class ExportManager {
   private final ProducerTaskFactory producerTaskFactory;
   private final Object lock = new Object();
 
+  /**
+   * Constructs an {@code ExportManager} that uses a {@link DistributedStorage} instance for
+   * non-transactional data export operations.
+   *
+   * @param distributedStorage the {@link DistributedStorage} used to read data directly from
+   *     storage
+   * @param dao the {@link ScalarDbDao} used to perform data operations
+   * @param producerTaskFactory the factory for creating producer tasks to format the exported data
+   */
   public ExportManager(
       DistributedStorage distributedStorage,
       ScalarDbDao dao,
@@ -52,6 +61,15 @@ public ExportManager(
     this.producerTaskFactory = producerTaskFactory;
   }
 
+  /**
+   * Constructs an {@code ExportManager} that uses a {@link DistributedTransactionManager} instance
+   * for transactional data export operations.
+   *
+   * @param distributedTransactionManager the {@link DistributedTransactionManager} used to read
+   *     data with transactional guarantees
+   * @param dao the {@link ScalarDbDao} used to perform data operations
+   * @param producerTaskFactory the factory for creating producer tasks to format the exported data
+   */
   public ExportManager(
       DistributedTransactionManager distributedTransactionManager,
       ScalarDbDao dao,

data-loader/core/src/main/java/com/scalar/db/dataloader/core/dataexport/JsonExportManager.java

@@ -9,13 +9,35 @@
 import java.io.Writer;
 
 public class JsonExportManager extends ExportManager {
+  /**
+   * Constructs a {@code JsonExportManager} for exporting data using a {@link DistributedStorage}
+   * instance.
+   *
+   * <p>This constructor is used when exporting data in non-transactional (storage) mode.
+   *
+   * @param distributedStorage the {@link DistributedStorage} used to read data directly from
+   *     storage
+   * @param dao the {@link ScalarDbDao} used to interact with ScalarDB for exporting data
+   * @param producerTaskFactory the factory used to create producer tasks for generating
+   *     CSV-formatted output
+   */
   public JsonExportManager(
       DistributedStorage distributedStorage,
       ScalarDbDao dao,
       ProducerTaskFactory producerTaskFactory) {
     super(distributedStorage, dao, producerTaskFactory);
   }
 
+  /**
+   * Constructs a {@code JsonExportManager} for exporting data using a {@link
+   * DistributedTransactionManager}.
+   *
+   * @param distributedTransactionManager the transaction manager used to read data with
+   *     transactional guarantees
+   * @param dao the {@link ScalarDbDao} used to interact with ScalarDB for exporting data
+   * @param producerTaskFactory the factory used to create producer tasks for generating
+   *     CSV-formatted output
+   */
   public JsonExportManager(
       DistributedTransactionManager distributedTransactionManager,
       ScalarDbDao dao,

data-loader/core/src/main/java/com/scalar/db/dataloader/core/dataexport/JsonLineExportManager.java

@@ -9,13 +9,35 @@
 import java.io.Writer;
 
 public class JsonLineExportManager extends ExportManager {
+  /**
+   * Constructs a {@code JsonLineExportManager} for exporting data using a {@link
+   * DistributedStorage} instance.
+   *
+   * <p>This constructor is used when exporting data in non-transactional (storage) mode.
+   *
+   * @param distributedStorage the {@link DistributedStorage} used to read data directly from
+   *     storage
+   * @param dao the {@link ScalarDbDao} used to interact with ScalarDB for exporting data
+   * @param producerTaskFactory the factory used to create producer tasks for generating
+   *     CSV-formatted output
+   */
   public JsonLineExportManager(
       DistributedStorage distributedStorage,
       ScalarDbDao dao,
       ProducerTaskFactory producerTaskFactory) {
     super(distributedStorage, dao, producerTaskFactory);
   }
 
+  /**
+   * Constructs a {@code JsonLineExportManager} for exporting data using a {@link
+   * DistributedTransactionManager}.
+   *
+   * @param distributedTransactionManager the transaction manager used to read data with
+   *     transactional guarantees
+   * @param dao the {@link ScalarDbDao} used to interact with ScalarDB for exporting data
+   * @param producerTaskFactory the factory used to create producer tasks for generating
+   *     CSV-formatted output
+   */
   public JsonLineExportManager(
       DistributedTransactionManager distributedTransactionManager,
       ScalarDbDao dao,