Accessing Thrift Server to Read Data

Function Description

Input the host where the ThriftServer instance is located and the port that provides services, create a Thrift client, access the Thrift Server instance, and use the GET and Scan commands to read data.

Example Code

• Invoking methods

  // Get data with single get.
  getData(client, TABLE_NAME);
  
  // Get data with getlist.
  getDataList(client, TABLE_NAME);
  
  // Scan data.
   scanData(client, TABLE_NAME);

• Using the get method to write data.

  The following code snippets are in the getData method in the ThriftSample class of the hbase-thrift-example\src\main\java\com\huawei\hadoop\hbase\examples packet.

  private void getData(THBaseService.Iface client, String tableName) throws TException {
       LOGGER.info("Test getData.");
       TGet get = new TGet();
       get.setRow("row1".getBytes());
  
       ByteBuffer table = ByteBuffer.wrap(tableName.getBytes());
       TResult result = client.get(table, get);
       printResult(result);
       LOGGER.info("Test getData done.");
   }

• Using getlist to read data

  The following code snippets are in the getDataList method in the ThriftSample class of the hbase-thrift-example\src\main\java\com\huawei\hadoop\hbase\examples packet.

  private void getDataList(THBaseService.Iface client, String tableName) throws TException {
       LOGGER.info("Test getDataList.");
       List<TGet> getList = new ArrayList<>();
       TGet get1 = new TGet();
       get1.setRow("row1".getBytes());
       getList.add(get1);
  
       TGet get2 = new TGet();
       get2.setRow("row2".getBytes());
       getList.add(get2);
  
       ByteBuffer table = ByteBuffer.wrap(tableName.getBytes());
       List<TResult> resultList = client.getMultiple(table, getList);
       for (TResult tResult : resultList) {
           printResult(tResult);
       }
       LOGGER.info("Test getDataList done.");
   }

• Using the scan method to write data

  The following code snippets are in the scanData method in the ThriftSample class of the hbase-thrift-example\src\main\java\com\huawei\hadoop\hbase\examples packet.

  private void scanData(THBaseService.Iface client, String tableName) throws TException {
       LOGGER.info("Test scanData.");
       int scannerId = -1;
       try {
           ByteBuffer table = ByteBuffer.wrap(tableName.getBytes());
           TScan scan = new TScan();
           scan.setLimit(500);
           scannerId = client.openScanner(table, scan);
           List<TResult> resultList = client.getScannerRows(scannerId, 100);
           while (resultList != null && !resultList.isEmpty()) {
               for (TResult tResult : resultList) {
                   printResult(tResult);
               }
               resultList = client.getScannerRows(scannerId, 100);
           }
       } finally {
           if (scannerId != -1) {
               client.closeScanner(scannerId);
               LOGGER.info("Closed scanner {}.", scannerId);
           }
       }
       LOGGER.info("Test scanData done.");
   }