code: public static ClassLoader getDefault() {
          ClassLoader loader = null;
          try {
              loader = Thread.currentThread().getContextClassLoader();
          } catch (Exception ignored) {
          }
          if (loader == null) {
              loader = Environment.class.getClassLoader();
              if (loader == null) {
                  try {
                      // getClassLoader() returning null indicates the bootstrap ClassLoader
                      loader = ClassLoader.getSystemClassLoader();
                  } catch (Exception e) {
                      // Cannot access system ClassLoader - oh well, maybe the caller can live with null...
                  }
              }
          }
          return loader;
      }
docs: Get current thread context ClassLoader
  
  @return return ClassLoader