in src/main/java/com/amazonaws/neptune/auth/NeptuneSigV4SignerBase.java [394:401]
public NeptuneSigV4Signature(
final String hostHeader, final String xAmzDateHeader, final String authorizationHeader,
final String sessionToken) {
this.hostHeader = hostHeader;
this.xAmzDateHeader = xAmzDateHeader;
this.authorizationHeader = authorizationHeader;
this.sessionToken = sessionToken;
}