Examples of Scan

cellmate.accumulo.reader.scan.Scan
Returns the internal scan
com.denimgroup.threadfix.data.entities.Scan
net.sf.mzmine.data.Scan
This class represent one spectrum of a raw data file.
org.apache.drill.common.logical.data.Scan
org.apache.hadoop.hbase.client.Scan
Used to perform Scan operations.
All operations are identical to {@link Get} with the exception ofinstantiation. Rather than specifying a single row, an optional startRow and stopRow may be defined. If rows are not specified, the Scanner will iterate over all rows.
To scan everything for each row, instantiate a Scan object.
To modify scanner caching for just this scan, use {@link #setCaching(int) setCaching}. If caching is NOT set, we will use the caching value of the hosting {@link HTable}. See {@link HTable#setScannerCaching(int)}.
To further define the scope of what to get when scanning, perform additional methods as outlined below.
To get all columns from specific families, execute {@link #addFamily(byte[]) addFamily}for each family to retrieve.
To get specific columns, execute {@link #addColumn(byte[],byte[]) addColumn}for each column to retrieve.
To only retrieve columns within a specific range of version timestamps, execute {@link #setTimeRange(long,long) setTimeRange}.
To only retrieve columns with a specific timestamp, execute {@link #setTimeStamp(long) setTimestamp}.
To limit the number of versions of each column to be returned, execute {@link #setMaxVersions(int) setMaxVersions}.
To limit the maximum number of values returned for each call to next(), execute {@link #setBatch(int) setBatch}.
To add a filter, execute {@link #setFilter(org.apache.hadoop.hbase.filter.Filter) setFilter}.
Expert: To explicitly disable server-side block caching for this scan, execute {@link #setCacheBlocks(boolean)}.

Examples of org.apache.hadoop.hbase.client.Scan


    Configuration c = new Configuration(this.conf);
    this.hbaseCluster = new MiniHBaseCluster(c, numMasters, numSlaves);
    // Don't leave here till we've done a successful scan of the .META.
    HTable t = new HTable(c, HConstants.META_TABLE_NAME);
    ResultScanner s = t.getScanner(new Scan());
    while (s.next() != null) {
      continue;
    }
    s.close();
    t.close();

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Examples of org.apache.hadoop.hbase.client.Scan

   */
  public void restartHBaseCluster(int servers) throws IOException, InterruptedException {
    this.hbaseCluster = new MiniHBaseCluster(this.conf, servers);
    // Don't leave here till we've done a successful scan of the .META.
    HTable t = new HTable(new Configuration(this.conf), HConstants.META_TABLE_NAME);
    ResultScanner s = t.getScanner(new Scan());
    while (s.next() != null) {
      // do nothing
    }
    LOG.info("HBase has been restarted");
    s.close();

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Examples of org.apache.hadoop.hbase.client.Scan

   * @return HTable to that new table
   * @throws IOException
   */
  public HTable truncateTable(byte [] tableName) throws IOException {
    HTable table = new HTable(getConfiguration(), tableName);
    Scan scan = new Scan();
    ResultScanner resScan = table.getScanner(scan);
    for(Result res : resScan) {
      Delete del = new Delete(res.getRow());
      table.delete(del);
    }

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Examples of org.apache.hadoop.hbase.client.Scan


  /**
   * Return the number of rows in the given table.
   */
  public int countRows(final HTable table) throws IOException {
    Scan scan = new Scan();
    ResultScanner results = table.getScanner(scan);
    int count = 0;
    for (@SuppressWarnings("unused") Result res : results) {
      count++;
    }

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Examples of org.apache.hadoop.hbase.client.Scan

    results.close();
    return count;
  }


  public int countRows(final HTable table, final byte[]... families) throws IOException {
    Scan scan = new Scan();
    for (byte[] family: families) {
      scan.addFamily(family);
    }
    ResultScanner results = table.getScanner(scan);
    int count = 0;
    for (@SuppressWarnings("unused") Result res : results) {
      count++;

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Examples of org.apache.hadoop.hbase.client.Scan


  /**
   * Return an md5 digest of the entire contents of a table.
   */
  public String checksumRows(final HTable table) throws Exception {
    Scan scan = new Scan();
    ResultScanner results = table.getScanner(scan);
    MessageDigest digest = MessageDigest.getInstance("MD5");
    for (Result res : results) {
      digest.update(res.getRow());
    }

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Examples of org.apache.hadoop.hbase.client.Scan

   */
  public List<byte[]> getMetaTableRows() throws IOException {
    // TODO: Redo using MetaReader class
    HTable t = new HTable(new Configuration(this.conf), HConstants.META_TABLE_NAME);
    List<byte[]> rows = new ArrayList<byte[]>();
    ResultScanner s = t.getScanner(new Scan());
    for (Result result : s) {
      LOG.info("getMetaTableRows: row -> " +
        Bytes.toStringBinary(result.getRow()));
      rows.add(result.getRow());
    }

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Examples of org.apache.hadoop.hbase.client.Scan

   */
  public List<byte[]> getMetaTableRows(byte[] tableName) throws IOException {
    // TODO: Redo using MetaReader.
    HTable t = new HTable(new Configuration(this.conf), HConstants.META_TABLE_NAME);
    List<byte[]> rows = new ArrayList<byte[]>();
    ResultScanner s = t.getScanner(new Scan());
    for (Result result : s) {
      byte[] val = result.getValue(HConstants.CATALOG_FAMILY, HConstants.REGIONINFO_QUALIFIER);
      if (val == null) {
        LOG.error("No region info for row " + Bytes.toString(result.getRow()));
        // TODO figure out what to do for this new hosed case.

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Examples of org.apache.hadoop.hbase.client.Scan

  public void waitUntilAllRegionsAssigned(final int countOfRegions)
  throws IOException {
    HTable meta = new HTable(getConfiguration(), HConstants.META_TABLE_NAME);
    while (true) {
      int rows = 0;
      Scan scan = new Scan();
      scan.addColumn(HConstants.CATALOG_FAMILY, HConstants.SERVER_QUALIFIER);
      ResultScanner s = meta.getScanner(scan);
      for (Result r = null; (r = s.next()) != null;) {
        byte [] b =
          r.getValue(HConstants.CATALOG_FAMILY, HConstants.SERVER_QUALIFIER);
        if (b == null || b.length <= 0) {

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Examples of org.apache.hadoop.hbase.client.Scan

   * has no actual methods of querying itself, and relies on StoreScanner.
   */
  public static List<KeyValue> getFromStoreFile(Store store,
                                                Get get) throws IOException {
    MultiVersionConsistencyControl.resetThreadReadPoint();
    Scan scan = new Scan(get);
    InternalScanner scanner = (InternalScanner) store.getScanner(scan,
        scan.getFamilyMap().get(store.getFamily().getName()));


    List<KeyValue> result = new ArrayList<KeyValue>();
    scanner.next(result);
    if (!result.isEmpty()) {
      // verify that we are on the row we want:

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