Accessing ThriftServer to Read Data

Updated on 2022-09-14 GMT+08:00

View PDF

Function

After importing the host where the ThriftServer instances are located and the port that provides services, you can create a Thrift client using the authentication credential and configuration file, access the ThriftServer, and use get and scan methods 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 the getlist method to write 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.");
 }

Parent topic: Example Code Description

Previous topic: Accessing ThriftServer to Write Data

Next topic: Using HBase Dual-Read