import java.sql.*;

public class ThreadConnection {

	public static void main(String args[]) throws Exception {
		Class.forName("org.postgresql.Driver");

		for (int i=0; i<20; i++) {
			Connector con = new Connector(i+1);
			new Thread(con, "Conn").start();
		}
	}

	static class Connector implements Runnable {
		private int _num;
		Connector(int n) {
			_num = n;
		}

		public void run() {
			for (int i=0; i<1000; i++) {
				try {
					Connection conn = DriverManager.getConnection("jdbc:postgresql://localhost:5432/jurka","jurka","");
					// System.out.println("Connector " + _num + " made connection #" + (i+1));
					conn.close();
				} catch (SQLException sqle) {
					sqle.printStackTrace();
					System.exit(1);
				}
			}
		}
	}

}