lmdbjni exmaple

lmdbjni

public class Tests {
  static Path dir = Paths.get("/tmp/test");
  static Database test;
  static Env env;
  static {
    try {
      FileUtils.deleteIfExist(dir);
      Files.createDirectory(dir);
    } catch (IOException e) {
      e.printStackTrace();
    }

    env = new Env();
    env.open(dir.toFile().getAbsolutePath());
    env.setMapSize(4294967296L);
    test = env.openDatabase("test");

  }

  public static void main(String[] args) {
    Transaction tx = env.createTransaction();
    for (int i = 0; i < 10000000; i++) {
      if (i % 10000 == 0) {
        tx.commit();
        tx = env.createTransaction();
        System.out.println(i);
      }
      test.put(tx, fromLong(i), new byte[] {3, 2, 1});
    }
  }

  public static byte[] fromLong(final long n) {
    final byte[] b = new byte[8];
    setLong(b, n);
    return b;
  }

  private static void setLong(final byte[] b, final long n) {
    setLong(b, n, 0);
  }

  private static void setLong(final byte[] b, final long n, final int offset) {
    b[offset + 0] = (byte) (n >>> 56);
    b[offset + 1] = (byte) (n >>> 48);
    b[offset + 2] = (byte) (n >>> 40);
    b[offset + 3] = (byte) (n >>> 32);
    b[offset + 4] = (byte) (n >>> 24);
    b[offset + 5] = (byte) (n >>> 16);
    b[offset + 6] = (byte) (n >>>  8);
    b[offset + 7] = (byte) (n >>>  0);
  }
}