UserRegistryJdbcImpl

/* Copyright (c) 1995 Sun Microsystems, Inc. All Rights reserved
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file copyright.html
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*/
/**
* JdbcImplementation of the UserRegistry.
* Table created as follows:
* create table UTH(
* userid varchar(50) UNIQUE,
* password varchar (50),
* email varchar (50)
* ) tablespace register
* @author Tony Squier
* @version 1.2 97/01/14 09:49:30
*/
import java.util.*;
import java.sql.*;
import jdc.database.*;
public class UserRegistryJdbcImpl implements UserRegistry
{
/**
* Name of Table entries are queried from.
*/
final static private String _driver = "sun.jdbc.odbc.JdbcOdbcDriver";
final static private String _user = "scott";
final static private String _pass = "tiger";
final static private String _url = "jdbc:odbc:jdc";
/**
* Database Connection.
*/
static private Properties _dbProperties = null;
static private Driver _jdbcDriver = null;
static private Connection _db = null;
/**
* Insert and Update statements
*/
static private PreparedStatement _insertStatement;
static private PreparedStatement _updateStatement;
static private PreparedStatement _queryStatement;
/**
* Initialize driver. We do this hear so that we only have
* one driver to use for all instances of this class.
*/
static
{
try
{
_jdbcDriver = (Driver)Class.forName (_driver).newInstance();
_dbProperties = new Properties();
_dbProperties.put ("user", _user);
_dbProperties.put ("password", _pass);
_init();
}
catch (Exception e)
{
e.printStackTrace();
}
}
/**
* Returns an array of found JDCMembers
* @param userId Search text.
* @return JDCMember[] Array JDCMembers instances found in the database.
* @throws JDCAdminException Error occured in database.
*/
public JDCMember[] getMember (String userId) throws JDCAdminException
{
Vector members = new Vector();
String sql;
ResultSet r = null;
Statement statement = null;
synchronized (_jdbcDriver)
{
try
{
// Check to see if the database connection
// is still open, if not re-open.
if ( _db.isClosed () )
{
_init();
}
// Now, lets do the query.
JDCMember member;
_queryStatement.setString (1, userId);
r = _queryStatement.executeQuery();
while ( r.next() )
{
member = new JDCMember ();
member.setUserId (r.getString ("USERID"));
member.setPassword (r.getString ("PASSWORD"));
member.setEmail (r.getString ("EMAIL"));
member.clearChanged();
members.addElement (member);
}
}
catch (SQLException e)
{
throw new JDCAdminException (e.getMessage());
}
finally
{
try
{
_queryStatement.clearParameters();
}
catch (SQLException e)
{
e.printStackTrace();
}
try
{
if ( r != null )
{
r.close();
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
}
JDCMember memberArray[] = new JDCMember[members.size()];
members.copyInto (memberArray);
return memberArray;
}
/**
* Adds a member to the database.
* @param member The JDCMember to add/replace.
* @return JDCMember The original value of the member or null if
* it didn't exist.
* @throws JDCAdminException
*/
public JDCMember setMember (JDCMember member) throws JDCAdminException
{
JDCMember hold[];
JDCMember oldMember = null;
ResultSet results = null;
PreparedStatement statement = null;
// See if member exists
hold = getMember (member.getUserId());
synchronized (_jdbcDriver)
{
try
{
// Check to see if the database connection
// is still open, if not re-open.
if ( _db.isClosed () )
{
_init();
}
int resultCode;
// We've found an existing member, so keep it because
// we return the old value. Also, we must do an update
// not an insert.
if ( hold.length == 1 )
{
oldMember = hold[0];
_updateStatement.setString (1, member.getPassword());
_updateStatement.setString (2, member.getEmail());
_updateStatement.setString (3, member.getUserId());
statement = _updateStatement;
resultCode = statement.executeUpdate();
}
// No existing member, so do an insert.
else if ( hold.length == 0 )
{
_insertStatement.setString (1, member.getUserId());
_insertStatement.setString (2, member.getPassword());
_insertStatement.setString (3, member.getEmail());
statement = _insertStatement;
resultCode = statement.executeUpdate ();
}
// More then one member with the given user id is in the
// database - this should never happen if we are
// using user id as a unqiue key.
else
{
throw new JDCAdminException ("Duplicate UserId!");
}
// Problem occured while doing the update/insert.
if ( resultCode == -1 )
{
throw new JDCAdminException ("Result Code: " + resultCode);
}
}
catch (SQLException e)
{
String s = e.getMessage();
throw new JDCAdminException (e.getMessage());
}
finally
{
if ( statement != null )
{
try
{
statement.clearParameters();
}
catch (SQLException e)
{
e.printStackTrace();
}
}
}
}
return oldMember;
}
/**
* Convience method to initalize the database connection
* and create the Prepared statements.
* @return void
*/
static private void _init()
{
synchronized (_jdbcDriver)
{

try

{

_db = _jdbcDriver.connect (_url, _dbProperties);

_insertStatement = _db.prepareStatement ("insert into UTH (userid,password,email) values (?,?,?)");

_updateStatement = _db.prepareStatement ("update UTH set password=?,email=? where userid=?");

_queryStatement = _db.prepareStatement ("select * from UTH where userid=?");

}

catch (SQLException e)

{

e.printStackTrace();

}

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