001    /**
002     * Copyright 2007 Mike Kroutikov.
003     *
004     * This program is free software; you can redistribute it and/or modify
005     *   it under the terms of the Lesser GNU General Public License as 
006     *   published by the Free Software Foundation; either version 3 of
007     *   the License, or (at your option) any later version.
008     *
009     *   This program is distributed in the hope that it will be useful,
010     *   but WITHOUT ANY WARRANTY; without even the implied warranty of
011     *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
012     *   Lesser GNU General Public License for more details.
013     *
014     *   You should have received a copy of the Lesser GNU General Public License
015     *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
016     */
017    
018    package org.otfeed.protocol.request;
019    
020    /**
021     * Helper class to validate parameters.
022     */
023    public final class Check {
024            
025            private Check() { }
026            
027            /**
028             * Throws NullPointerException with the appropriate message
029             * if <code>obj</code> parameter is null.
030             * 
031             * @param obj object to check.
032             * @param name name of the object to display as part of the
033             *              exception message.
034             */
035            public static void notNull(Object obj, String name) {
036                    if(obj == null) {
037                            throw new NullPointerException(name + " can not be null");
038                    }
039            }
040            
041            public static void isTrue(boolean predicate, String message) {
042                    if(!predicate) {
043                            throw new IllegalArgumentException(message);
044                    }
045            }
046    }