content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * 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 com.alibaba.nacos.common.utils;
  
  import java.io.InputStream;
  import java.util.Comparator;
  import java.util.Objects;
  import java.util.Properties;
  
  /**
   * Version utils.
   *
   * @author xingxuechao on:2019/2/27 12:32 PM
   */
  public class VersionUtils {
  
      private VersionUtils() {
      }
      
      public static String version;
      
      private static String clientVersion;
      
      /**
       * current version.
       */
      public static final String VERSION_PLACEHOLDER = "${project.version}";
      
      private static final String NACOS_VERSION_FILE = "nacos-version.txt";
      
      static {
          try (InputStream in = VersionUtils.class.getClassLoader().getResourceAsStream(NACOS_VERSION_FILE)) {
              Properties props = new Properties();
              props.load(in);
              String val = props.getProperty("version");
              if (val != null && !VERSION_PLACEHOLDER.equals(val)) {
                  version = val;
                  clientVersion = "Nacos-Java-Client:v" + VersionUtils.version;
              }
          } catch (Exception e) {
              e.printStackTrace();
          }
      }
      
      private static final Comparator<String> STRING_COMPARATOR = String::compareTo;
      
      /**
       * compare two version who is latest.
       *
       * @param versionA version A, like x.y.z(-beta)
       * @param versionB version B, like x.y.z(-beta)
       * @return compare result
       */
      public static int compareVersion(final String versionA, final String versionB) {
          final String[] sA = versionA.split("\\.");
          final String[] sB = versionB.split("\\.");
          int expectSize = 3;
          if (sA.length != expectSize || sB.length != expectSize) {
              throw new IllegalArgumentException("version must be like x.y.z(-beta)");
          }
          int first = Objects.compare(sA[0], sB[0], STRING_COMPARATOR);
          if (first != 0) {
              return first;
          }
          int second = Objects.compare(sA[1], sB[1], STRING_COMPARATOR);
          if (second != 0) {
              return second;
          }
          return Objects.compare(sA[2].split("-")[0], sB[2].split("-")[0], STRING_COMPARATOR);
      }
      
      public static String getFullClientVersion() {
          return clientVersion;
      }
  }
  