package com.atlassian.plugin.refimpl;
   
   import org.apache.commons.io.IOUtils;
   
   import java.io.IOException;
   import java.io.InputStream;
   import java.util.Properties;
   
   /**
   * Utility class for system exports.
   *
   * @since 2.14.0
   */
  public class SystemExportVersionUtils {
      private SystemExportVersionUtils() {
      }
  
      private static final String GUAVA_PROPERTY_PATH = "META-INF/maven/com.google.guava/guava/pom.properties";
  
      /**
       * Retrieves version number of the bundled google guava.
       *
       * @return version of google guava
       */
      public static String getGoogleGuavaVersion() {
          InputStream inputStream = null;
  
          try {
              inputStream = SystemExportVersionUtils.class.getClassLoader().getResourceAsStream(GUAVA_PROPERTY_PATH);
  
              if (inputStream == null) {
                  throw new IllegalStateException("google guava is required in classpath for refapp to function");
              }
  
              Properties props = new Properties();
              try {
                  props.load(inputStream);
              } catch (IOException e) {
                  throw new IllegalStateException("cannot read the bundled google guava version file");
              }
  
              final String guavaVersion = props.getProperty("version");
              if (guavaVersion == null) {
                  throw new IllegalStateException("cannot extract google guava version from the bundled version file");
              }
  
              return guavaVersion;
          } finally {
              IOUtils.closeQuietly(inputStream);
          }
      }
  }