Class Gc

src/tools/diskcache/Gc.java:39–125

Standalone disk cache garbage collection utility.

/** Standalone disk cache garbage collection utility. */
public final class Gc {

  private Gc() {}

  /** Command line options. */
  public static final class Options extends OptionsBase {

    @Option(
        name = "disk_cache",
        defaultValue = "null",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help = "Path to disk cache.")
    public String diskCache;

    @Option(
        name = "max_size",
        defaultValue = "0",
        converter = ByteSizeConverter.class,
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help =
            "The target size for the disk cache. If set to a positive value, older entries will be"
                + " deleted as required to reach this size.")
    public long maxSize;

    @Option(
        name = "max_age",
        defaultValue = "0",
        documentationCategory = OptionDocumentationCategory.UNCATEGORIZED,
        effectTags = {OptionEffectTag.UNKNOWN},
        help =
            "The target age for the disk cache. If set to a positive value, entries exceeding this"
                + " age will be deleted.")
    public Duration maxAge;
  }

  private static final ExecutorService executorService =
      Executors.newFixedThreadPool(
          max(4, Runtime.getRuntime().availableProcessors()),
          new ThreadFactoryBuilder().setNameFormat("disk-cache-gc-%d").build());

  public static void main(String[] args) throws Exception {
    OptionsParser op = OptionsParser.builder().optionsClasses(Options.class).build();
    op.parseAndExitUponError(args);

    Options options = op.getOptions(Options.class);

    if (options.diskCache == null) {
      System.err.println("--disk_cache must be specified.");
      System.exit(1);
    }

    if (options.maxSize <= 0 && options.maxAge.isZero()) {
      System.err.println(
          "At least one of --max_size or --max_age must be set to a positive value.");
      System.exit(1);
    }