001    // Copyright 2008 Thiago H. de Paula Figueiredo
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package br.com.arsmachina.authentication.controller;
016    
017    /**
018     * Interface used to encrypt passwords. It is recommended to use a secure cryptographic hash
019     * function, but any one can used (including no encrypting at all).
020     * 
021     * @author Thiago H. de Paula Figueiredo
022     */
023    public interface PasswordEncrypter {
024    
025            /**
026             * Encrypts a <code>password</code>. If it is encrypted already, it must return it
027             * unchanged.
028             * 
029             * @param password a {@link String}. It cannot be null.
030             * @return a {@link String}.
031             */
032            public String encrypt(String password);
033            
034    }