datasourcerealm.java

业界著名的tomcat服务器的最新6.0的源代码。

            validated = (digest(credentials).equals(dbCredentials));

        if (validated) {
            if (containerLog.isTraceEnabled())
                containerLog.trace(
                    sm.getString("dataSourceRealm.authenticateSuccess",
                                 username));
        } else {
            if (containerLog.isTraceEnabled())
                containerLog.trace(
                    sm.getString("dataSourceRealm.authenticateFailure",
                                 username));
            return (null);
        }

        ArrayList list = getRoles(dbConnection, username);

        // Create and return a suitable Principal for this user
        return (new GenericPrincipal(this, username, credentials, list));

    }


    /**
     * Close the specified database connection.
     *
     * @param dbConnection The connection to be closed
     */
    protected void close(Connection dbConnection) {

        // Do nothing if the database connection is already closed
        if (dbConnection == null)
            return;

        // Commit if not auto committed
        try {
            if (!dbConnection.getAutoCommit()) {
                dbConnection.commit();
            }            
        } catch (SQLException e) {
            containerLog.error("Exception committing connection before closing:", e);
        }

        // Close this database connection, and log any errors
        try {
            dbConnection.close();
        } catch (SQLException e) {
            containerLog.error(sm.getString("dataSourceRealm.close"), e); // Just log it here
        }

    }

    /**
     * Open the specified database connection.
     *
     * @return Connection to the database
     */
    protected Connection open() {

        try {
            Context context = null;
            if (localDataSource) {
                context = ContextBindings.getClassLoader();
                context = (Context) context.lookup("comp/env");
            } else {
                StandardServer server = 
                    (StandardServer) ServerFactory.getServer();
                context = server.getGlobalNamingContext();
            }
            DataSource dataSource = (DataSource)context.lookup(dataSourceName);
	    return dataSource.getConnection();
        } catch (Exception e) {
            // Log the problem for posterity
            containerLog.error(sm.getString("dataSourceRealm.exception"), e);
        }  
        return null;
    }

    /**
     * Return a short name for this Realm implementation.
     */
    protected String getName() {

        return (name);

    }

    /**
     * Return the password associated with the given principal's user name.
     */
    protected String getPassword(String username) {

        Connection dbConnection = null;

        // Ensure that we have an open database connection
        dbConnection = open();
        if (dbConnection == null) {
            return null;
        }

        try {
        	return getPassword(dbConnection, username);        	
        } finally {
            close(dbConnection);
        }
    }
    
    /**
     * Return the password associated with the given principal's user name.
     * @param dbConnection The database connection to be used
     * @param username Username for which password should be retrieved
     */
    protected String getPassword(Connection dbConnection, 
								 String username) {

        ResultSet rs = null;
        PreparedStatement stmt = null;
        String dbCredentials = null;

        try {
            stmt = credentials(dbConnection, username);
            rs = stmt.executeQuery();
            if (rs.next()) {
                dbCredentials = rs.getString(1);
            }

            return (dbCredentials != null) ? dbCredentials.trim() : null;
            
        } catch(SQLException e) {
            containerLog.error(
                    sm.getString("dataSourceRealm.getPassword.exception",
                                 username));
        } finally {
        	try {
	            if (rs != null) {
	                rs.close();
	            }
	            if (stmt != null) {
	                stmt.close();
	            }
        	} catch (SQLException e) {
                    containerLog.error(
                        sm.getString("dataSourceRealm.getPassword.exception",
        		             username));
        		
        	}
        }
        
        return null;
    }


    /**
     * Return the Principal associated with the given user name.
     */
    protected Principal getPrincipal(String username) {
    	Connection dbConnection = open();
        if (dbConnection == null) {
            return new GenericPrincipal(this,username, null, null);
        }
        try {
        	return (new GenericPrincipal(this,
        			username,
					getPassword(dbConnection, username),
					getRoles(dbConnection, username)));
        } finally {
        	close(dbConnection);
        }

    }

    /**
     * Return the roles associated with the given user name.
     * @param username Username for which roles should be retrieved
     */
    protected ArrayList getRoles(String username) {

        Connection dbConnection = null;

        // Ensure that we have an open database connection
        dbConnection = open();
        if (dbConnection == null) {
            return null;
        }

        try {
            return getRoles(dbConnection, username);
        } finally {
        	close(dbConnection);
        }
    }
    
    /**
     * Return the roles associated with the given user name
     * @param dbConnection The database connection to be used
     * @param username Username for which roles should be retrieved
     */
    protected ArrayList getRoles(Connection dbConnection,
                                     String username) {
    	
        ResultSet rs = null;
        PreparedStatement stmt = null;
        ArrayList list = null;
    	
        try {
    		stmt = roles(dbConnection, username);
    		rs = stmt.executeQuery();
    		list = new ArrayList();
    		
    		while (rs.next()) {
    			String role = rs.getString(1);
    			if (role != null) {
    				list.add(role.trim());
    			}
    		}
    		return list;
    	} catch(SQLException e) {
            containerLog.error(
                sm.getString("dataSourceRealm.getRoles.exception", username));
        }
    	finally {
        	try {
	            if (rs != null) {
	                rs.close();
	            }
	            if (stmt != null) {
	                stmt.close();
	            }
        	} catch (SQLException e) {
                    containerLog.error(
                        sm.getString("dataSourceRealm.getRoles.exception",
                                     username));
        	}
        }
    	
    	return null;
    }

    /**
     * Return a PreparedStatement configured to perform the SELECT required
     * to retrieve user credentials for the specified username.
     *
     * @param dbConnection The database connection to be used
     * @param username Username for which credentials should be retrieved
     *
     * @exception SQLException if a database error occurs
     */
    private PreparedStatement credentials(Connection dbConnection,
                                            String username)
        throws SQLException {

        PreparedStatement credentials =
            dbConnection.prepareStatement(preparedCredentials);

        credentials.setString(1, username);
        return (credentials);

    }
    
    /**
     * Return a PreparedStatement configured to perform the SELECT required
     * to retrieve user roles for the specified username.
     *
     * @param dbConnection The database connection to be used
     * @param username Username for which roles should be retrieved
     *
     * @exception SQLException if a database error occurs
     */
    private PreparedStatement roles(Connection dbConnection, String username)
        throws SQLException {

        PreparedStatement roles = 
            dbConnection.prepareStatement(preparedRoles);

        roles.setString(1, username);
        return (roles);

    }

    // ------------------------------------------------------ Lifecycle Methods


    /**
     *
     * Prepare for active use of the public methods of this Component.
     *
     * @exception LifecycleException if this component detects a fatal error
     *  that prevents it from being started
     */
    public void start() throws LifecycleException {

        // Perform normal superclass initialization
        super.start();

        // Create the roles PreparedStatement string
        StringBuffer temp = new StringBuffer("SELECT ");
        temp.append(roleNameCol);
        temp.append(" FROM ");
        temp.append(userRoleTable);
        temp.append(" WHERE ");
        temp.append(userNameCol);
        temp.append(" = ?");
        preparedRoles = temp.toString();

        // Create the credentials PreparedStatement string
        temp = new StringBuffer("SELECT ");
        temp.append(userCredCol);
        temp.append(" FROM ");
        temp.append(userTable);
        temp.append(" WHERE ");
        temp.append(userNameCol);
        temp.append(" = ?");
        preparedCredentials = temp.toString();
    }


    /**
     * Gracefully shut down active use of the public methods of this Component.
     *
     * @exception LifecycleException if this component detects a fatal error
     *  that needs to be reported
     */
    public void stop() throws LifecycleException {

        // Perform normal superclass finalization
        super.stop();

    }


}