Java Sample Code

To use the Drill JDBC driver in an application, you must include all of the JAR files from the ZIP archive in the classpath for the Java project.

The following Java code demonstrates how to use the JDBC API to:

• Register the driver for Drill
• Establish a connection to a Drill server
• Query the database
• Parse a result set
• Handle exceptions
• Clean up to avoid memory leakage

// java.sql packages are required
import java.sql.*;
class DrillJDBCExample {
     // Define a string as the fully qualified class name
     // (FQCN) of the desired JDBC driver
       private static final String JDBC_DRIVER =
       "com.mapr.drill.jdbc.Driver";
     // Define a string as the connection URL
        private static final String CONNECTION_URL =
        "jdbc:drill:drillbit=192.168.1.1:31010";
 
            public static void main(String[] args) {
                Connection con = null;
                Statement stmt = null;
                ResultSet rs = null;
    // Define a plain query
       String query = "SELECT first_name, last_name, emp_id
       FROM `hive`.`default`.`emp`";
 
                try {
 
                    // Register the driver using the class name
                    Class.forName(JDBC_DRIVER);
                    // Establish a connection using the connection
                    // URL
                    con = DriverManager.getConnection(CONNECTION_
                    URL);
                    // Create a Statement object for sending SQL
                    // statements to the database
                    stmt = con.createStatement();
 
                    // Execute the SQL statement
                    rs = stmt.executeQuery(query);
                    // Display a header line for output appearing in
                    // the Console View
                    System.out.printf("%20s%20s%20s\r\n", "FIRST
                    NAME", "LAST NAME" , "EMPLOYEE ID");
 
                    // Step through each row in the result set
                    // returned from the database
                    while(rs.next()) {
                        // Retrieve values from the row where the
 
                        // cursor is currently positioned using
                        // column names
                        String FirstName = rs.getString("first_
                        name");
                        String LastName = rs.getString("last_name");
                        String EmployeeID = rs.getString("emp_id");
 
                    // Display values in columns 20 characters
                    // wide in the Console View using the
                    // Formatter
                    System.out.printf("%20s%20s%20s\r\n",
                    FirstName, LastName, EmployeeID);
                    }
                } catch (SQLException se) {
                    // Handle errors encountered during interaction
                    // with the data source
                } catch (Exception e) {
                    // Handle other errors
                } finally {
                    // Perform clean up
                try {
                    if (rs != null) {
                        rs.close();
                    }
                } catch (SQLException se1) {
                    // Log this
                }
                try {
                    if (stmt != null) {
                        stmt.close();
                }
                } catch (SQLException se2) {
                    // Log this
                }
                try {
                    if (con != null) {
                        con.close();
                    }
                } catch (SQLException se3) {
                    // Log this
                } // End try
            } // End try
        } // End main
    } // End DrillJDBCExample