jdbc (java.util.)Properties file

[jon80]

This code snippet reads from a file named 'database.properties', however, I would like to know what format should the properties be written?

I'm trying to connect to a postgre database, hence, included file named postgresql-8.3-604.jdbc4.jar within the project.

import java.sql.*;
import java.io.*;
import java.util.*;

 /**
   This program tests that the database and the JDBC
    driver are correctly configured.
*/
class TestDB
{
    public static void main (String args[])
    {
       try
       {
          runTest();
       }
       catch (SQLException ex)
      {
          while (ex != null)
          {
             ex.printStackTrace();
             ex = ex.getNextException();
          }
       }
       catch (IOException ex)
       {
          ex.printStackTrace();
       }
    }

    /**
       Runs a test by creating a table, adding a value, showing the table contents, and
       removing the table.
    */
    public static void runTest()
       throws SQLException, IOException
    {
       Connection conn = getConnection();
       try
       {
          Statement stat = conn.createStatement();

          stat.execute("CREATE TABLE Greetings (Message CHAR(20))");
          stat.execute("INSERT INTO Greetings VALUES ('Hello, World!')");
          ResultSet result = stat.executeQuery("SELECT * FROM Greetings");
          result.next();
          System.out.println(result.getString(1));
          stat.execute("DROP TABLE Greetings");
       }
       finally
       {
          conn.close();
       }
    }

    /**
       Gets a connection from the properties specified
       in the file database.properties
       @return the database connection
    */
    public static Connection getConnection()
       throws SQLException, IOException
    {
       Properties props = new Properties();
       FileInputStream in = new FileInputStream("database.properties");
       props.load(in);
       in.close();

       String drivers = props.getProperty("jdbc.drivers");
       if (drivers != null)
          System.setProperty("jdbc.drivers", drivers);
       String url = props.getProperty("jdbc.url");
       String username = props.getProperty("jdbc.username");
       String password = props.getProperty("jdbc.password");

       return DriverManager.getConnection(url, username, password);
    }
}

References
1. Core Java Vol II 7th Ed.
2. The API