public static void doTestAppend() throws Exception {
    ThriftHBaseServiceHandler handler = new ThriftHBaseServiceHandler(UTIL.getConfiguration(),
      UserProvider.instantiate(UTIL.getConfiguration()));
    handler.createTable(tableAname, getColumnDescriptors());
    try {
      List<Mutation> mutations = new ArrayList<>(1);
      mutations.add(new Mutation(false, columnAname, valueAname, true));
      handler.mutateRow(tableAname, rowAname, mutations, null);

      List<ByteBuffer> columnList = new ArrayList<>(1);
      columnList.add(columnAname);
      List<ByteBuffer> valueList = new ArrayList<>(1);
      valueList.add(valueBname);

      TAppend append = new TAppend(tableAname, rowAname, columnList, valueList);
      handler.append(append);

      TRowResult rowResult = handler.getRow(tableAname, rowAname, null).get(0);
      assertEquals(rowAname, rowResult.row);
      assertArrayEquals(Bytes.add(valueAname.array(), valueBname.array()),
        rowResult.columns.get(columnAname).value.array());
    } finally {
      handler.disableTable(tableAname);
      handler.deleteTable(tableAname);
    }
  }
Appends the value to a cell and checks that the cell value is updated properly.
hbase-thrift/src/test/java/org/apache/hadoop/hbase/thrift/TestThriftServer.java