Updated on 2022-11-18 GMT+08:00

Accessing Hive Data Sources Using HSBroker

Description

This section describes how to use HSBroker to connect to HetuEngine, assemble SQL statements, and send the SQL statements to HetuEngine for execution to add, delete, modify, and query Hive data sources.
public class JDBCExampleBroker {
    private static Properties properties = new Properties();
    private static void init() throws ClassNotFoundException {
        properties.setProperty("user", "YourUserName");
        properties.setProperty("SSL", "false");
        Class.forName("io.prestosql.jdbc.PrestoDriver");
    }
    /**
     * Program entry
     *
     * @param args no need program parameter
     */
    public static void main(String[] args) {
        Connection connection = null;
        ResultSet result = null;
        PreparedStatement statement = null;
        String url = "jdbc:presto://192.168.1.130:29861,192.168.1.131:29861/hive/default?serviceDiscoveryMode=hsbroker";
        try {
            init();
            String sql = "show tables";
            connection = DriverManager.getConnection(url, properties);
            statement = connection.prepareStatement(sql.trim());
            result = statement.executeQuery();
            ResultSetMetaData resultMetaData = result.getMetaData();
            Integer colNum = resultMetaData.getColumnCount();
            for (int j = 1; j <= colNum; j++) {
                System.out.print(resultMetaData.getColumnLabel(j) + "\t");
            }
            System.out.println();
            while (result.next()) {
                for (int j = 1; j <= colNum; j++) {
                    System.out.print(result.getString(j) + "\t");
                }
                System.out.println();
            }
        } catch (SQLException | ClassNotFoundException e) {
            e.printStackTrace();
        } finally {
            if (result != null) {
                try {
                    result.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
            if (statement != null) {
                try {
                    statement.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
            if (connection != null) {
                try {
                    connection.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

Table 1 describes the parameters in the preceding code.

Table 1 Parameter description

Parameter

Description

url

jdbc:presto://HSBroker1_IP:HSBroker1_Port,HSBroker2_IP:HSBroker2_Port,HSBroker3_IP:HSBroker3_Port/catalog/schema?serviceDiscoveryMode=hsbroker

NOTE:
  • catalog and schema indicate the names of the catalog and schema to be connected to the JDBC client, respectively.
  • HSBroker_IP:HSBroker_Port: indicates the HSBroker URL. Use commas (,) to separate multiple URLs, for example, 192.168.81.37:2181,192.168.195.232:2181,192.168.169.84:2181.

user

Username for accessing HetuEngine, that is, the username of the machine-machine user created in the cluster.

SSL

Indicates whether to use the HTTPS connection. The default value is false.