Threading

runner.java

package dk.madsravn;


import java.sql.*;

public class runner {

    public static void main(String[] args) {
        // Let's connect to the database first

        ThreadStarter ts = new ThreadStarter();
      while(true) {
          ts.check();
          try {
              Thread.sleep(4000);
          } catch (Exception e) {
              System.err.println(e);
          }


      }
    }
}

TheadStarter.java

package dk.madsravn;

import org.apache.commons.dbcp.BasicDataSource;

import javax.sql.DataSource;
import java.sql.*;
import java.util.Calendar;

/**
 * Created with IntelliJ IDEA.
 * User: mads
 * Date: 8/18/13
 * Time: 1:13 AM
 * To change this template use File | Settings | File Templates.
 */
public class ThreadStarter {

    void threadMessage(String message) {
        String threadName =
                Thread.currentThread().getName();
        System.out.format("%s: %s%n",
                threadName,
                message);
    }


    private class MessageLoop
            implements Runnable {
        private int id;
        private Connection con;
        MessageLoop(int id, DataSource ds) {
            this.id = id;
            try {
                this.con = ds.getConnection();
            } catch(Exception e) {

            }
        }
        public void run() {
            String importantInfo[] = {
                    "Mares eat oats",
                    "Does eat oats",
                    "Little lambs eat ivy",
                    "A kid will eat ivy too"
            };
            try {
                startTime(id);
                for (int i = 0;
                     i < importantInfo.length;
                     i++) {
                    // Pause for 4 seconds
                    Thread.sleep(4000);
                    // Print a message
                    threadMessage(importantInfo[i]);
                }


            } catch (InterruptedException e) {
                threadMessage("I wasn't done!");
            } catch(Exception e) {
                System.err.println(e);
            } finally {
                stopTime(id);
            }
        }

        private void stopTime(int id) {
            System.out.println("Stopping");
            long time = Calendar.getInstance().getTime().getTime()/1000;
            String query = "UPDATE jobs SET stop=? WHERE id=?";
            try {
                //Connection con = ds.getConnection();
                if(con!=null) {
                    PreparedStatement setStop = con.prepareStatement(query);
                    setStop.setLong(1, time);
                    setStop.setInt(2, id);
                    setStop.executeQuery();

                }
            } catch(Exception e) {
                System.err.println("Stop " + e);
            }
        }

        private void startTime(int id) {
            System.out.println("Starting");
            long time = Calendar.getInstance().getTime().getTime()/1000;
            String query = "UPDATE jobs SET start=? WHERE id=?";
            try {
                //Connection con = ds.getConnection();
                if(con!=null) {
                    PreparedStatement setStart = con.prepareStatement(query);
                    setStart.setLong(1, time);
                    setStart.setInt(2, id);
                    setStart.executeQuery();
                    con.close();
                }
            } catch(Exception e) {
                System.err.println("Start " + e);
            }
        }
    }



    private DataSource ds;

    ThreadStarter() {
        ds = setupDataSource();

    }

    public DataSource setupDataSource() {
        BasicDataSource ds = new BasicDataSource();
        ds.setDriverClassName("org.postgresql.Driver");
        ds.setUsername("postgres");
        ds.setPassword("code");
        ds.setUrl("jdbc:postgresql://localhost:5432/threads");
        return ds;
    }

    public void check() {
        Statement stmt = null;
        String query =
                "SELECT id, start, stop, command" +
                        "  FROM jobs WHERE start = ?;";
        System.out.println("Checking");
        try {
            Connection con = ds.getConnection();
            if(con != null) {
                PreparedStatement findID = con.prepareStatement(query);
                findID.setInt(1, -1);
                ResultSet rs = findID.executeQuery();
                //ResultSet rs = stmt.executeQuery(query);
                while(rs.next()) {
                    Thread t = new Thread(new MessageLoop(rs.getInt(1),ds));
                    t.start();

                }

            con.close();
            }
        } catch (Exception e ) {
            System.err.println(e);
        } finally {
            try {
                if(stmt != null) {
                    stmt.close();
                }

            } catch (Exception e) {
                System.err.println(e);
            }
        }
    }

    public void startThread(int id) {

        //TODO: Selection is not necessary here.
        Statement stmt = null;
        String query =
                "SELECT id, start, stop, command" +
                        "  FROM jobs where id = ? ;";

        try {
            Connection con = ds.getConnection();
            if(con != null) {
                PreparedStatement findID = con.prepareStatement(query);
                findID.setInt(1, id);
                ResultSet rs = findID.executeQuery();
                //ResultSet rs = stmt.executeQuery(query);

                rs.next(); // Call to go to the first
                System.out.println("Is first: " + rs.isFirst());
                System.out.println(rs.getInt(1) + ", " + rs.getInt(2) + ", " + rs.getInt(3) + ", " + rs.getString(4));

            }
        } catch (Exception e ) {
            System.err.println(e);
        } finally {
            try {
                if(stmt != null) {
                    stmt.close();
                }

            } catch (Exception e) {
                System.err.println(e);
            }
        }


    }



    public void close() {
        try {
            BasicDataSource bds = (BasicDataSource) ds;
            bds.close();
        } catch (Exception e) {
            System.err.println("Couldn't close BasicDataSource " + e);
        }
    }

}