package simpledb;

import java.io.*;

/** Database is a class that initalizes several static
    variables used by the database system (the catalog, the buffer pool, 
    and the log files, in particular.)
    <p>
    Provides a set of methods that can be used to access these global variables
    from anywhere.
*/

public class Database {
    private static Catalog _catalog = new Catalog();
    private static BufferPool _bufferpool =  BufferPool.createBufferPool();

    private Database() {
    }

    /** Return the static instance of the buffer pool */
    public static BufferPool getBufferPool() {
	return _bufferpool;
    }

    /** Return the static instance of the catalog */
    public static Catalog getCatalog() {
	return _catalog;
    }

    /** Method used for testing -- create a new instance of the 
	buffer pool and return it
    */
    public static BufferPool resetBufferPool() {
	_bufferpool = BufferPool.createBufferPool();
	return _bufferpool;
    }

}