@Override
    public boolean equals(@Nullable Object o) {
        if (this == o) {
            return true;
        }
        if (!(o instanceof OAuth2Token)) {
            return false;
        }
        final OAuth2Token that = (OAuth2Token) o;
        return secureEquals(accessToken, that.accessToken);
    }
Returns the string that is sent as the value of the {@link HttpHeaderNames#AUTHORIZATION} header.
core/src/main/java/com/linecorp/armeria/common/auth/OAuth2Token.java