Method getNumberAsLong

core/src/main/java/io/grpc/internal/JsonUtil.java:187–211

Gets a number from an object for the given key, casted to an long. If the key is not present, this returns null. If the value does not represent a long integer, throws an exception.

(Map<String, ?> obj, String key)

   * exception.
   */
  public static Long getNumberAsLong(Map<String, ?> obj, String key) {
    assert key != null;
    if (!obj.containsKey(key)) {
      return null;
    }
    Object value = obj.get(key);
    if (value instanceof Double) {
      Double d = (Double) value;
      long l = d.longValue();
      if (l != d) {
        throw new ClassCastException("Number expected to be long: " + d);
      }
      return l;
    }
    if (value instanceof String) {
      try {
        return Long.parseLong((String) value);
      } catch (NumberFormatException e) {
        throw new IllegalArgumentException(
            String.format("value '%s' for key '%s' is not a long integer", value, key));
      }
    }
    throw new IllegalArgumentException(
        String.format("value '%s' for key '%s' is not a long integer", value, key));
  }

  /**
   * Gets a string from an object for the given key.  If the key is not present, this returns null.