Closing Database Connections in Java

Question

I am getting a little confused, I was reading the below from http://en.wikipedia.org/wiki/Java_Database_Connectivity

Connection conn = DriverManager.getConn         


        

Answer 1

Actually, it is best if you use a try-with-resources block and Java will close all of the connections for you when you exit the try block.

You should do this with any object that implements AutoClosable.

try (Connection connection = getDatabaseConnection(); Statement statement = connection.createStatement()) {
    String sqlToExecute = "SELECT * FROM persons";
    try (ResultSet resultSet = statement.execute(sqlToExecute)) {
        if (resultSet.next()) {
            System.out.println(resultSet.getString("name");
        }
    }
} catch (SQLException e) {
    System.out.println("Failed to select persons.");
}

The call to getDatabaseConnection is just made up. Replace it with a call that gets you a JDBC SQL connection or a connection from a pool.