[HUDI-357] Refactor hudi-cli based on new comment and code style rules (#1051)

hudi-cli/src/main/java/org/apache/hudi/cli/HoodieCLI.java

@@ -25,6 +25,9 @@ import org.apache.hudi.common.table.HoodieTableMetaClient;
 import org.apache.hudi.common.util.ConsistencyGuardConfig;
 import org.apache.hudi.common.util.FSUtils;
 
+/**
+ * This class is responsible to load table metadata and hoodie related configs.
+ */
 public class HoodieCLI {
 
   public static Configuration conf;
@@ -35,6 +38,9 @@ public class HoodieCLI {
   public static HoodieTableMetaClient tableMetadata;
   public static HoodieTableMetaClient syncTableMetadata;
 
+  /**
+   * Enum for CLI state.
+   */
   public enum CLIState {
     INIT, DATASET, SYNC
   }

hudi-cli/src/main/java/org/apache/hudi/cli/HoodieHistoryFileNameProvider.java

@@ -23,6 +23,9 @@ import org.springframework.core.annotation.Order;
 import org.springframework.shell.plugin.support.DefaultHistoryFileNameProvider;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI history file provider.
+ */
 @Component
 @Order(Ordered.HIGHEST_PRECEDENCE)
 public class HoodieHistoryFileNameProvider extends DefaultHistoryFileNameProvider {

hudi-cli/src/main/java/org/apache/hudi/cli/HoodiePrintHelper.java

@@ -25,12 +25,12 @@ import java.util.function.Function;
 import org.apache.hudi.common.util.Option;
 
 /**
- * Helper class to render table for hoodie-cli
+ * Helper class to render table for hoodie-cli.
  */
 public class HoodiePrintHelper {
 
   /**
-   * Print header and raw rows
+   * Print header and raw rows.
    *
    * @param header Header
    * @param rows Raw Rows
@@ -41,7 +41,7 @@ public class HoodiePrintHelper {
   }
 
   /**
-   * Serialize Table to printable string
+   * Serialize Table to printable string.
    *
    * @param rowHeader Row Header
    * @param fieldNameToConverterMap Field Specific Converters
@@ -71,7 +71,7 @@ public class HoodiePrintHelper {
   }
 
   /**
-   * Render rows in Table
+   * Render rows in Table.
    *
    * @param buffer Table
    * @return output
@@ -86,7 +86,7 @@ public class HoodiePrintHelper {
   }
 
   /**
-   * Render only header of the table
+   * Render only header of the table.
    *
    * @param header Table Header
    * @return output
@@ -98,7 +98,7 @@ public class HoodiePrintHelper {
   }
 
   /**
-   * Print Text table
+   * Print Text table.
    *
    * @param headers Headers
    * @param data Table

hudi-cli/src/main/java/org/apache/hudi/cli/HoodiePrompt.java

@@ -23,6 +23,9 @@ import org.springframework.core.annotation.Order;
 import org.springframework.shell.plugin.support.DefaultPromptProvider;
 import org.springframework.stereotype.Component;
 
+/**
+ * This class deals with displaying prompt on CLI based on the state.
+ */
 @Component
 @Order(Ordered.HIGHEST_PRECEDENCE)
 public class HoodiePrompt extends DefaultPromptProvider {

hudi-cli/src/main/java/org/apache/hudi/cli/HoodieSplashScreen.java

@@ -24,6 +24,9 @@ import org.springframework.shell.plugin.support.DefaultBannerProvider;
 import org.springframework.shell.support.util.OsUtils;
 import org.springframework.stereotype.Component;
 
+/**
+ * This class is responsible to print the splash screen at the start of the application.
+ */
 @Component
 @Order(Ordered.HIGHEST_PRECEDENCE)
 public class HoodieSplashScreen extends DefaultBannerProvider {

hudi-cli/src/main/java/org/apache/hudi/cli/Main.java

@@ -21,11 +21,11 @@ package org.apache.hudi.cli;
 import java.io.IOException;
 import org.springframework.shell.Bootstrap;
 
+/**
+ * Main class that delegates to Spring Shell's Bootstrap class in order to simplify debugging inside an IDE.
+ */
 public class Main {
 
-  /**
-   * Main class that delegates to Spring Shell's Bootstrap class in order to simplify debugging inside an IDE
-   */
   public static void main(String[] args) throws IOException {
     System.out.println("Main called");
     new HoodieSplashScreen();

hudi-cli/src/main/java/org/apache/hudi/cli/Table.java

@@ -63,7 +63,7 @@ public class Table implements Iterable<List<String>> {
   }
 
   /**
-   * Main API to add row to the table
+   * Main API to add row to the table.
    * 
    * @param row Row
    */
@@ -82,7 +82,7 @@ public class Table implements Iterable<List<String>> {
   }
 
   /**
-   * Add all rows
+   * Add all rows.
    * 
    * @param rows Rows to be aded
    * @return
@@ -93,7 +93,7 @@ public class Table implements Iterable<List<String>> {
   }
 
   /**
-   * Add all rows
+   * Add all rows.
    * 
    * @param rows Rows to be added
    * @return
@@ -104,7 +104,7 @@ public class Table implements Iterable<List<String>> {
   }
 
   /**
-   * API to let the table know writing is over and reading is going to start
+   * API to let the table know writing is over and reading is going to start.
    */
   public Table flip() {
     this.finishedAdding = true;
@@ -113,7 +113,7 @@ public class Table implements Iterable<List<String>> {
   }
 
   /**
-   * Sorting of rows by a specified field
+   * Sorting of rows by a specified field.
    * 
    * @return
    */

hudi-cli/src/main/java/org/apache/hudi/cli/TableHeader.java

@@ -22,7 +22,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 /**
- * Header for the table to be rendered
+ * Header for the table to be rendered.
  */
 public class TableHeader {
 
@@ -30,7 +30,7 @@ public class TableHeader {
   private final List<String> fieldNames = new ArrayList<>();
 
   /**
-   * Add a field (column) to table
+   * Add a field (column) to table.
    *
    * @param fieldName field Name
    */
@@ -40,14 +40,14 @@ public class TableHeader {
   }
 
   /**
-   * Get all field names
+   * Get all field names.
    */
   public List<String> getFieldNames() {
     return fieldNames;
   }
 
   /**
-   * Index of the field in the table
+   * Index of the field in the table.
    *
    * @param fieldName Field Name
    */
@@ -56,14 +56,14 @@ public class TableHeader {
   }
 
   /**
-   * Lookup field by offset
+   * Lookup field by offset.
    */
   public String get(int index) {
     return fieldNames.get(index);
   }
 
   /**
-   * Get number of fields in the table
+   * Get number of fields in the table.
    */
   public int getNumFields() {
     return fieldNames.size();

hudi-cli/src/main/java/org/apache/hudi/cli/commands/ArchivedCommitsCommand.java

@@ -45,6 +45,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display archived commits and stats if available.
+ */
 @Component
 public class ArchivedCommitsCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/CleansCommand.java

@@ -39,6 +39,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to show cleans options.
+ */
 @Component
 public class CleansCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/CommitsCommand.java

@@ -44,6 +44,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display commits options.
+ */
 @Component
 public class CommitsCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/CompactionCommand.java

@@ -59,6 +59,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display compaction related options.
+ */
 @Component
 public class CompactionCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/DatasetsCommand.java

@@ -35,6 +35,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display hudi dataset options.
+ */
 @Component
 public class DatasetsCommand implements CommandMarker {
 
@@ -67,7 +70,7 @@ public class DatasetsCommand implements CommandMarker {
   }
 
   /**
-   * Create a Hoodie Table if it does not exist
+   * Create a Hoodie Table if it does not exist.
    *
    * @param path Base Path
    * @param name Hoodie Table Name
@@ -113,7 +116,7 @@ public class DatasetsCommand implements CommandMarker {
   }
 
   /**
-   * Describes table properties
+   * Describes table properties.
    */
   @CliCommand(value = "desc", help = "Describle Hoodie Table properties")
   public String descTable() {

hudi-cli/src/main/java/org/apache/hudi/cli/commands/FileSystemViewCommand.java

@@ -47,6 +47,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display file system options.
+ */
 @Component
 public class FileSystemViewCommand implements CommandMarker {
 
@@ -206,7 +209,7 @@ public class FileSystemViewCommand implements CommandMarker {
   }
 
   /**
-   * Build File System View
+   * Build File System View.
    * 
    * @param globRegex Path Regex
    * @param maxInstant Max Instants to be used for displaying file-instants

hudi-cli/src/main/java/org/apache/hudi/cli/commands/HDFSParquetImportCommand.java

@@ -33,6 +33,9 @@ import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 import scala.collection.JavaConverters;
 
+/**
+ * CLI command for importing parquet dataset to hudi dataset.
+ */
 @Component
 public class HDFSParquetImportCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/HoodieLogFileCommand.java

@@ -59,6 +59,9 @@ import org.springframework.stereotype.Component;
 import scala.Tuple2;
 import scala.Tuple3;
 
+/**
+ * CLI command to display log file options.
+ */
 @Component
 public class HoodieLogFileCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/HoodieSyncCommand.java

@@ -32,6 +32,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display sync options.
+ */
 @Component
 public class HoodieSyncCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/RepairsCommand.java

@@ -34,6 +34,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display and trigger repair options.
+ */
 @Component
 public class RepairsCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/RollbacksCommand.java

@@ -42,6 +42,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display rollback options.
+ */
 @Component
 public class RollbacksCommand implements CommandMarker {
 
@@ -115,7 +118,7 @@ public class RollbacksCommand implements CommandMarker {
   }
 
   /**
-   * An Active timeline containing only rollbacks
+   * An Active timeline containing only rollbacks.
    */
   class RollbackTimeline extends HoodieActiveTimeline {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/SavepointsCommand.java

@@ -40,6 +40,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display savepoint options.
+ */
 @Component
 public class SavepointsCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/SparkMain.java

@@ -35,12 +35,15 @@ import org.apache.log4j.Logger;
 import org.apache.spark.api.java.JavaSparkContext;
 import org.apache.spark.sql.SQLContext;
 
+/**
+ * This class deals with initializing spark context based on command entered to hudi-cli.
+ */
 public class SparkMain {
 
   protected static final Logger LOG = Logger.getLogger(SparkMain.class);
 
   /**
-   * Commands
+   * Commands.
    */
   enum SparkCommand {
     ROLLBACK, DEDUPLICATE, ROLLBACK_TO_SAVEPOINT, SAVEPOINT, IMPORT, UPSERT, COMPACT_SCHEDULE, COMPACT_RUN, COMPACT_UNSCHEDULE_PLAN, COMPACT_UNSCHEDULE_FILE, COMPACT_VALIDATE, COMPACT_REPAIR

hudi-cli/src/main/java/org/apache/hudi/cli/commands/StatsCommand.java

@@ -47,6 +47,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to displays stats options.
+ */
 @Component
 public class StatsCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/commands/UtilsCommand.java

@@ -23,6 +23,9 @@ import org.springframework.shell.core.annotation.CliCommand;
 import org.springframework.shell.core.annotation.CliOption;
 import org.springframework.stereotype.Component;
 
+/**
+ * CLI command to display utils.
+ */
 @Component
 public class UtilsCommand implements CommandMarker {
 

hudi-cli/src/main/java/org/apache/hudi/cli/utils/CommitUtil.java

@@ -25,6 +25,9 @@ import org.apache.hudi.common.table.HoodieTableMetaClient;
 import org.apache.hudi.common.table.HoodieTimeline;
 import org.apache.hudi.common.table.timeline.HoodieInstant;
 
+/**
+ * Utilities related to commit operation.
+ */
 public class CommitUtil {
 
   public static long countNewRecords(HoodieTableMetaClient target, List<String> commitsToCatchup) throws IOException {

hudi-cli/src/main/java/org/apache/hudi/cli/utils/HiveUtil.java

@@ -26,6 +26,9 @@ import java.sql.Statement;
 import org.apache.hudi.common.table.HoodieTableMetaClient;
 import org.joda.time.DateTime;
 
+/**
+ * Hive connection related utilities.
+ */
 public class HiveUtil {
 
   private static final String driverName = "org.apache.hive.jdbc.HiveDriver";

hudi-cli/src/main/java/org/apache/hudi/cli/utils/InputStreamConsumer.java

@@ -24,6 +24,9 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.util.logging.Logger;
 
+/**
+ * This class is responsible to read a Process output.
+ */
 public class InputStreamConsumer extends Thread {
 
   protected static final Logger LOG = Logger.getLogger(InputStreamConsumer.class.getName());

hudi-cli/src/main/java/org/apache/hudi/cli/utils/SparkUtil.java

@@ -29,13 +29,16 @@ import org.apache.spark.SparkConf;
 import org.apache.spark.api.java.JavaSparkContext;
 import org.apache.spark.launcher.SparkLauncher;
 
+/**
+ * Utility functions dealing with Spark.
+ */
 public class SparkUtil {
 
   public static Logger logger = Logger.getLogger(SparkUtil.class);
   public static final String DEFUALT_SPARK_MASTER = "yarn-client";
 
   /**
-   * TODO: Need to fix a bunch of hardcoded stuff here eg: history server, spark distro
+   * TODO: Need to fix a bunch of hardcoded stuff here eg: history server, spark distro.
    */
   public static SparkLauncher initLauncher(String propertiesFile) throws URISyntaxException {
     String currentJar = new File(SparkUtil.class.getProtectionDomain().getCodeSource().getLocation().toURI().getPath())