content: /*
   *  Copyright (C) 2019 Alpha Jiang. All rights reserved.
   *
   *  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.
   *
   */
  
  package io.github.alphajiang.hyena.utils;
  
  import java.util.Collection;
  
  public class CollectionUtils {
      public static boolean isEmpty(final Collection<?> coll) {
          return coll == null || coll.isEmpty();
      }
  
      public static boolean isNotEmpty(final Collection<?> coll) {
          return !CollectionUtils.isEmpty(coll);
      }
  
      public static String join(final Collection<?> coll, String separate) {
          if (isEmpty(coll)) {
              return "";
          }
          StringBuilder buf = new StringBuilder();
          coll.stream().filter(a -> a != null).forEach(o -> {
  
              if (o instanceof Character) {
                  buf.append(separate).append((Character) o);
              } else if (o instanceof String) {
                  if (StringUtils.isNotBlank((String) o)) {
                      buf.append(separate).append((String) o);
                  }
              } else {
                  buf.append(separate).append(o.toString());
              }
          });
          if (buf.length() < separate.length()) {
              return "";
          } else {
              return buf.substring(separate.length());
          }
      }
  
  }
  