001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.shiro.authc;
020
021/**
022 * Thrown when an authentication attempt has been received for an account that has already been
023 * authenticated (i.e. logged-in), and the system is configured to prevent such concurrent access.
024 *
025 * <p>This is useful when an application must ensure that only one person is logged-in to a single
026 * account at any given time.
027 *
028 * <p>Sometimes account names and passwords are lazily given away
029 * to many people for easy access to a system.  Such behavior is undesirable in systems where
030 * users are accountable for their actions, such as in government applications, or when licensing
031 * agreements must be maintained, such as those which only allow 1 user per paid license.
032 *
033 * <p>By disallowing concurrent access, such systems can ensure that each authenticated session
034 * corresponds to one and only one user at any given time.
035 *
036 * @since 0.1
037 */
038public class ConcurrentAccessException extends AccountException {
039
040    /**
041     * Creates a new ConcurrentAccessException.
042     */
043    public ConcurrentAccessException() {
044        super();
045    }
046
047    /**
048     * Constructs a new ConcurrentAccessException.
049     *
050     * @param message the reason for the exception
051     */
052    public ConcurrentAccessException(String message) {
053        super(message);
054    }
055
056    /**
057     * Constructs a new ConcurrentAccessException.
058     *
059     * @param cause the underlying Throwable that caused this exception to be thrown.
060     */
061    public ConcurrentAccessException(Throwable cause) {
062        super(cause);
063    }
064
065    /**
066     * Constructs a new ConcurrentAccessException.
067     *
068     * @param message the reason for the exception
069     * @param cause   the underlying Throwable that caused this exception to be thrown.
070     */
071    public ConcurrentAccessException(String message, Throwable cause) {
072        super(message, cause);
073    }
074
075}