StringUtils.java

/* 
 * Licensed under the Apache License, Version 2.0 (the "License");
 *
 * You may not use this file except in compliance with the License.
 *
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Contributions from 2013-2017 where performed either by US government 
 * employees, or under US Veterans Health Administration contracts. 
 *
 * US Veterans Health Administration contributions by government employees
 * are work of the U.S. Government and are not subject to copyright
 * protection in the United States. Portions contributed by government 
 * employees are USGovWork (17USC §105). Not subject to copyright. 
 * 
 * Contribution by contractors to the US Veterans Health Administration
 * during this period are contractually contributed under the
 * Apache License, Version 2.0.
 *
 * See: https://www.usa.gov/government-works
 * 
 * Contributions prior to 2013:
 *
 * Copyright (C) International Health Terminology Standards Development Organisation.
 * Licensed under the Apache License, Version 2.0.
 *
 */



package sh.isaac.api.util;

/**
 * {@link StringUtils}.
 *
 * @author <a href="mailto:daniel.armbrust.list@gmail.com">Dan Armbrust</a>
 */
public class StringUtils
        extends org.apache.commons.lang3.StringUtils {
   /**
    * Null-safe string compare.
    *
    * @param s1 the s 1
    * @param s2 the s 2
    * @return the int
    */
   public static int compareStringsIgnoreCase(String s1, String s2) {
      int rval = 0;

      if ((s1 != null) || (s2 != null)) {
         if (s1 == null) {
            rval = -1;
         } else if (s2 == null) {
            rval = 1;
         } else {
            return s1.compareToIgnoreCase(s2);
         }
      }

      return rval;
   }
}