Java Sample

// This trivial sample will select first 15 cities with the greatest number of medical examiners.

import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Date;

class JavaSample
{
  public JavaSample() throws SQLException
  {
    Connection conn;
    Statement stmt;
    ResultSet rs;
    int limit = 0;
    StringBuffer lineBuffer = new StringBuffer(50);
    
    String sql =
      "Select city, state, count(*) " +
      "from medical_examiners " +
      "group by city, state " +
      "order by 3 desc, 1 ";
    
    // Load the JDBC driver
    DriverManager.registerDriver(new org.postgresql.Driver());
    // Connect to the database. Replace "yourid" and "yourpassword" with your userid and password. The rest of
    // the parameters will not change.
    conn = DriverManager.getConnection ("jdbc:postgresql://aviationdb.net/aviation","yourid", "yourpassword");
    // Create a Statement
    stmt = conn.createStatement ();
    // prepare and execute the statement
    rs = stmt.executeQuery(sql);
    // format a heading line
    lineBuffer.setLength(50);
    lineBuffer.insert(0, "City"); 
    lineBuffer.insert(30, "State"); 
    lineBuffer.insert(50, "Count");
    String line = new String(lineBuffer); 
    System.out.println(line.trim());
    //Get all the rows
    while (rs.next ())
    {
      // get each of the returned columns and create a formatted line
      lineBuffer.setLength(0);
      lineBuffer.setLength(50);
      lineBuffer.insert(0, rs.getString (1)); 
      lineBuffer.insert(30, rs.getString (2)); 
      lineBuffer.insert(50, rs.getString (3));
      line = new String(lineBuffer); 
      System.out.println(line.trim());
      limit++;
      if (limit == 15)
        break;
    }
    // Close the ResultSet
    rs.close();
    // Close the Statement
    stmt.close();
    // Close the connection
    conn.close();
  }
  
  public static void main (String args [])
  {
    System.out.println("JavaSample started at " + new Date() + "\r\n");
    try
    {
      JavaSample js = new JavaSample();
    }
    catch (SQLException e)
    {
      e.printStackTrace();
    }
    System.out.println("\r\nJavaSample ended at " + new Date());
  }
}