Reverse thread argument deprecation for Data Loader CLI

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

@@ -54,14 +54,16 @@ public class ExportCommand extends ExportCommandOptions implements Callable<Inte
   public Integer call() throws Exception {
     validateDeprecatedOptions();
     applyDeprecatedOptions();
+    resolveDefaults();
+
     String scalarDbPropertiesFilePath = getScalarDbPropertiesFilePath();
 
     try {
       validateOutputDirectory();
       FileUtils.validateFilePath(scalarDbPropertiesFilePath);
       validatePositiveValue(
           spec.commandLine(), dataChunkSize, DataLoaderError.INVALID_DATA_CHUNK_SIZE);
-      validatePositiveValue(spec.commandLine(), maxThreads, DataLoaderError.INVALID_MAX_THREADS);
+      validatePositiveValue(spec.commandLine(), threadCount, DataLoaderError.INVALID_THREAD_COUNT);
 
       StorageFactory storageFactory = StorageFactory.create(scalarDbPropertiesFilePath);
       TableMetadataService metaDataService =
@@ -126,6 +128,8 @@ private void validateDeprecatedOptions() {
         DEPRECATED_END_EXCLUSIVE_OPTION,
         END_INCLUSIVE_OPTION,
         END_INCLUSIVE_OPTION_SHORT);
+    validateDeprecatedOptionPair(
+        spec.commandLine(), DEPRECATED_MAX_THREADS_OPTION, THREADS_OPTION, null);
   }
 
   private String getScalarDbPropertiesFilePath() {
@@ -170,7 +174,7 @@ private ExportOptions buildExportOptions(Key partitionKey, ScanRange scanRange)
             .includeTransactionMetadata(includeTransactionMetadata)
             .delimiter(delimiter)
             .limit(limit)
-            .maxThreadCount(maxThreads)
+            .threadCount(threadCount)
             .dataChunkSize(dataChunkSize)
             .prettyPrintJson(prettyPrintJson)
             .scanRange(scanRange);

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

@@ -16,6 +16,8 @@ public class ExportCommandOptions {
   public static final String END_INCLUSIVE_OPTION = "--end-inclusive";
   public static final String END_INCLUSIVE_OPTION_SHORT = "-ei";
   public static final String DEPRECATED_END_EXCLUSIVE_OPTION = "--end-exclusive";
+  public static final String THREADS_OPTION = "--threads";
+  public static final String DEPRECATED_MAX_THREADS_OPTION = "--max-threads";
 
   @CommandLine.Option(
       names = {"--config", "-c"},
@@ -73,11 +75,20 @@ public class ExportCommandOptions {
   protected boolean includeTransactionMetadata;
 
   @CommandLine.Option(
-      names = {"--max-threads", "-mt"},
-      paramLabel = "<MAX_THREADS>",
+      names = {"--threads"},
+      paramLabel = "<THREADS>",
       description =
-          "Maximum number of threads to use for parallel processing (default: number of available processors)")
-  protected int maxThreads;
+          "Number of threads to use for parallel processing (default: number of available processors)")
+  protected int threadCount;
+
+  // Deprecated option - kept for backward compatibility
+  @CommandLine.Option(
+      names = {DEPRECATED_MAX_THREADS_OPTION, "-mt"},
+      paramLabel = "<MAX_THREADS>",
+      description = "Deprecated: Use --threads instead",
+      hidden = true)
+  @Deprecated
+  protected Integer maxThreadsDeprecated;
 
   @CommandLine.Option(
       names = {"--start-key", "-sk"},
@@ -184,5 +195,24 @@ public void applyDeprecatedOptions() {
     if (endExclusiveDeprecated != null) {
       scanEndInclusive = !endExclusiveDeprecated;
     }
+
+    // If the deprecated option is set, use its value
+    if (maxThreadsDeprecated != null) {
+      threadCount = maxThreadsDeprecated;
+    }
+  }
+
+  /**
+   * Resolves default values for options.
+   *
+   * <p>This method is called AFTER applyDeprecatedOptions() to resolve any default values that
+   * depend on runtime information. For threadCount, a value of 0 indicates that the number of
+   * available processors should be used.
+   */
+  public void resolveDefaults() {
+    // Resolve threadCount: 0 means use available processors
+    if (threadCount == 0) {
+      threadCount = Runtime.getRuntime().availableProcessors();
+    }
   }
 }

data-loader/cli/src/main/java/com/scalar/db/dataloader/cli/command/dataimport/ImportCommand.java

@@ -55,13 +55,15 @@ public class ImportCommand extends ImportCommandOptions implements Callable<Inte
   public Integer call() throws Exception {
     validateDeprecatedOptions();
     applyDeprecatedOptions();
+    resolveDefaults();
+
     validateImportTarget(controlFilePath, namespace, tableName);
     validateLogDirectory(logDirectory);
     validatePositiveValue(
         spec.commandLine(), dataChunkSize, DataLoaderError.INVALID_DATA_CHUNK_SIZE);
     validatePositiveValue(
         spec.commandLine(), transactionSize, DataLoaderError.INVALID_TRANSACTION_SIZE);
-    validatePositiveValue(spec.commandLine(), maxThreads, DataLoaderError.INVALID_MAX_THREADS);
+    validatePositiveValue(spec.commandLine(), threadCount, DataLoaderError.INVALID_THREAD_COUNT);
     validatePositiveValue(
         spec.commandLine(), dataChunkQueueSize, DataLoaderError.INVALID_DATA_CHUNK_QUEUE_SIZE);
     ControlFile controlFile = parseControlFileFromPath(controlFilePath).orElse(null);
@@ -282,10 +284,7 @@ private Optional<ControlFile> parseControlFileFromPath(String controlFilePath) {
    */
   private void validateDeprecatedOptions() {
     validateDeprecatedOptionPair(
-        spec.commandLine(),
-        DEPRECATED_THREADS_OPTION,
-        MAX_THREADS_OPTION,
-        MAX_THREADS_OPTION_SHORT);
+        spec.commandLine(), DEPRECATED_MAX_THREADS_OPTION, THREADS_OPTION, null);
   }
 
   /**
@@ -308,7 +307,7 @@ private ImportOptions createImportOptions(ControlFile controlFile) {
             .namespace(namespace)
             .dataChunkSize(dataChunkSize)
             .transactionBatchSize(transactionSize)
-            .maxThreads(maxThreads)
+            .threadCount(threadCount)
             .dataChunkQueueSize(dataChunkQueueSize)
             .tableName(tableName);
 

data-loader/cli/src/main/java/com/scalar/db/dataloader/cli/command/dataimport/ImportCommandOptions.java

@@ -9,9 +9,8 @@
 public class ImportCommandOptions {
 
   public static final String FILE_OPTION_NAME_LONG_FORMAT = "--file";
-  public static final String MAX_THREADS_OPTION = "--max-threads";
-  public static final String MAX_THREADS_OPTION_SHORT = "-mt";
-  public static final String DEPRECATED_THREADS_OPTION = "--threads";
+  public static final String THREADS_OPTION = "--threads";
+  public static final String DEPRECATED_MAX_THREADS_OPTION = "--max-threads";
 
   @CommandLine.Option(
       names = {"--mode", "-m"},
@@ -35,21 +34,20 @@ public class ImportCommandOptions {
   protected String sourceFilePath;
 
   @CommandLine.Option(
-      names = {"--max-threads", "-mt"},
-      paramLabel = "<MAX_THREADS>",
+      names = {"--threads"},
+      paramLabel = "<THREADS>",
       description =
-          "Maximum number of threads to use for parallel processing (default: number of available processors)",
-      defaultValue = "16")
-  protected int maxThreads;
+          "Number of threads to use for parallel processing (default: number of available processors)")
+  protected int threadCount;
 
   // Deprecated option - kept for backward compatibility
   @CommandLine.Option(
-      names = {DEPRECATED_THREADS_OPTION},
-      paramLabel = "<THREADS>",
-      description = "Deprecated: Use --max-threads instead",
+      names = {DEPRECATED_MAX_THREADS_OPTION, "-mt"},
+      paramLabel = "<MAX_THREADS>",
+      description = "Deprecated: Use --threads instead",
       hidden = true)
   @Deprecated
-  protected Integer threadsDeprecated;
+  protected Integer maxThreadsDeprecated;
 
   @CommandLine.Option(
       names = {"--namespace", "-ns"},
@@ -180,8 +178,22 @@ public class ImportCommandOptions {
    */
   public void applyDeprecatedOptions() {
     // If the deprecated option is set, use its value
-    if (threadsDeprecated != null) {
-      maxThreads = threadsDeprecated;
+    if (maxThreadsDeprecated != null) {
+      threadCount = maxThreadsDeprecated;
+    }
+  }
+
+  /**
+   * Resolves default values for options.
+   *
+   * <p>This method is called AFTER applyDeprecatedOptions() to resolve any default values that
+   * depend on runtime information. For threadCount, a value of 0 indicates that the number of
+   * available processors should be used.
+   */
+  public void resolveDefaults() {
+    // Resolve threadCount: 0 means use available processors
+    if (threadCount == 0) {
+      threadCount = Runtime.getRuntime().availableProcessors();
     }
   }
 }

data-loader/cli/src/test/java/com/scalar/db/dataloader/cli/command/dataexport/ExportCommandTest.java

@@ -44,7 +44,7 @@ void removeFileIfCreated() {
   void call_withBlankScalarDBConfigurationFile_shouldThrowException() {
     exportCommand.configFilePath = "";
     exportCommand.dataChunkSize = 100;
-    exportCommand.maxThreads = 4;
+    exportCommand.threadCount = 4;
     exportCommand.namespace = "scalar";
     exportCommand.table = "asset";
     exportCommand.outputDirectory = "";
@@ -62,7 +62,7 @@ void call_withBlankScalarDBConfigurationFile_shouldThrowException() {
   void call_withInvalidScalarDBConfigurationFile_shouldReturnOne() throws Exception {
     exportCommand.configFilePath = "scalardb.properties";
     exportCommand.dataChunkSize = 100;
-    exportCommand.maxThreads = 4;
+    exportCommand.threadCount = 4;
     exportCommand.namespace = "scalar";
     exportCommand.table = "asset";
     exportCommand.outputDirectory = "";
@@ -190,4 +190,94 @@ void call_withOnlyDeprecatedEndExclusive_shouldApplyInvertedValue() {
     // end-exclusive=false should become end-inclusive=true
     assertEquals(true, command.scanEndInclusive);
   }
+
+  @Test
+  void call_withBothThreadsAndMaxThreads_shouldThrowException() {
+    assertBothDeprecatedAndNewOptionsThrowException(
+        "--max-threads=8", "--threads=16", "--max-threads", "--threads");
+  }
+
+  @Test
+  void call_withOnlyDeprecatedMaxThreads_shouldApplyValue() {
+    // Simulate command line parsing with only deprecated option
+    String[] args = {
+      "--config",
+      "scalardb.properties",
+      "--namespace",
+      "scalar",
+      "--table",
+      "asset",
+      "--format",
+      "JSON",
+      "--max-threads",
+      "12"
+    };
+    ExportCommand command = new ExportCommand();
+    CommandLine cmd = new CommandLine(command);
+    cmd.parseArgs(args);
+
+    // Verify the deprecated value was parsed
+    assertEquals(12, command.maxThreadsDeprecated);
+
+    // Apply deprecated options
+    command.applyDeprecatedOptions();
+
+    // Verify the value was applied to threadCount
+    assertEquals(12, command.threadCount);
+  }
+
+  @Test
+  void call_withOnlyThreads_shouldUseValue() {
+    // Simulate command line parsing with only new --threads option
+    String[] args = {
+      "--config",
+      "scalardb.properties",
+      "--namespace",
+      "scalar",
+      "--table",
+      "asset",
+      "--format",
+      "JSON",
+      "--threads",
+      "20"
+    };
+    ExportCommand command = new ExportCommand();
+    CommandLine cmd = new CommandLine(command);
+    cmd.parseArgs(args);
+
+    // Verify the value was set to threadCount
+    assertEquals(20, command.threadCount);
+
+    // Verify the deprecated value was not set
+    assertEquals(null, command.maxThreadsDeprecated);
+  }
+
+  @Test
+  void call_withDeprecatedShortOption_shouldApplyValue() {
+    // Simulate command line parsing with deprecated short option -mt
+    String[] args = {
+      "--config",
+      "scalardb.properties",
+      "--namespace",
+      "scalar",
+      "--table",
+      "asset",
+      "--format",
+      "JSON",
+      "-mt",
+      "15"
+    };
+    ExportCommand command = new ExportCommand();
+    CommandLine cmd = new CommandLine(command);
+    cmd.parseArgs(args);
+
+    // Verify the deprecated value was parsed
+    assertEquals(15, command.maxThreadsDeprecated);
+
+    // Apply deprecated options
+    command.applyDeprecatedOptions();
+
+    // Verify the value was applied to threadCount
+    assertEquals(15, command.threadCount);
+  }
 }