import java.io.*;
import java.security.*;
import java.security.acl.*;
import java.util.*;

import com.sun.server.realm.*;
import com.sun.server.realm.util.*;


public class DatabaseRealm extends Realm
{
	private FileAclInfo aclInfo = null;

	public DatabaseRealm()
	{
		super();
		aclInfo = new FileAclInfo(this);
	}	

	public Acl getAcl() throws BadRealmException
	{
		return aclInfo.getAcl();
	}

	public Enumeration getAclNames() throws BadRealmException
	{
		return aclInfo.getAclNames();
	}

	public Acl getAcl(String name) throws 
			NoSuchAclException,
			BadRealmException
	{
		return aclInfo.getAcl(name);	
	}

	public Acl addAcl(String name, Principal owner) 
		throws BadRealmException
	{
		return aclInfo.makeAcl(name, owner);
	}

	public void removeAcl(String name) throws
			NoSuchAclException, BadRealmException
	{
		aclInfo.deleteAcl(name);
	}

	public synchronized void init(Properties props) throws
		BadRealmException, NoSuchRealmException
	{
		try
		{
			super.init(props);

			// Do any database initilization here..
		}
		catch(Exception e)
		{
			throw new BadRealmException(e.getMessage());
		}
	}

	public Enumeration getGroupNames() throws BadRealmException
	{
		// Add JDBC code to get the group names here..
		// Or
		// throw the following exception
		throw new BadRealmException("Not Implemented.");
	}	

	public Group getGroup(String name) throws 
			NoSuchGroupException, BadRealmException
	{
		// Return a Group object stored within database
		// Or
		// throw the following exception
		throw new BadRealmException("Not Implemented.");
	}

	public Group addGroup(String name) throws
			InUseException, BadRealmException
	{
		// Add a Group with a given name within database.
		// Or
		// throw the following exception
		throw new BadRealmException("Not Implemented.");
	}

	public boolean removeGroup(String name) throws 
			InUseException, BadRealmException, NoSuchGroupException
	{
		// remove the group from within the database.
		// Or
		// throw the following exception
		throw new BadRealmException("Not Implemented.");
	}

	public Enumeration getUserNames() throws BadRealmException
	{
		// Query database & return a user list.
		// Or
		// throw the following exception
		throw new BadRealmException("Not Implemented.");
	}	

	public User getUser(String name) throws 
			NoSuchUserException, BadRealmException
	{
		// Query the database & return an object that is a subclass 
		// of RealmUser object.
		// For example. 
		//

		// return new DatabaseRealmUser(name, this);

		// Or
		// throw the following exception

		throw new BadRealmException("Not Implemented.");
	}

	public void deleteUser(String name) throws 
			InUseException, BadRealmException, NoSuchUserException
	{
		// add code to delete user within this realm
		// Or
		// throw the following exception
		throw new BadRealmException("Not Implemented.");
	}

	public Principal getDefaultAclOwner() throws BadRealmException
	{
		try
		{
				// change this to reflect the default ACL owner in your
				// realm.
				return getUser("admin");
		}
		catch(NoSuchUserException e)
		{
				throw new BadRealmException("Default Owner does not exist.");
		}
	}

	protected void setDefaultPolicies() throws BadRealmException
	{
		// Add default policies within this realm;
		// For example:
		// Existance of a user called "root" etc.
	}
}