Package com.adyen.util

Class HMACValidator

java.lang.Object

com.adyen.util.HMACValidator

public class HMACValidator
extends Object

Utility class for generating and validating HMAC signatures used in Adyen webhooks.

Field Summary

Fields

Modifier and Type	Field	Description
static String	DATA_SEPARATOR	Separator used when joining data for signature calculation.
static String	HMAC_SHA256_ALGORITHM	The HMAC algorithm used.

Constructor Summary

Constructors

Constructor	Description
HMACValidator()

Method Summary

Modifier and Type	Method	Description
String	calculateHMAC(NotificationRequestItem notificationRequestItem, String key)	Computes the HMAC SHA-256 signature for a given NotificationRequestItem.
String	calculateHMAC(String data, String key)	Computes the HMAC SHA-256 signature for the given data using the provided hex-encoded HMAC key.
String	getDataToSign(NotificationRequestItem notificationRequestItem)	Builds the concatenated data string from a NotificationRequestItem to be used in HMAC signature calculation.
boolean	validateHMAC(NotificationRequestItem notificationRequestItem, String key)	Validates the HMAC signature of an NotificationRequestItem.
boolean	validateHMAC(String hmacSignature, String hmacKey, String payload)	Validates an HMAC signature for generic webhooks (e.g.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

HMAC_SHA256_ALGORITHM

public static final String HMAC_SHA256_ALGORITHM

The HMAC algorithm used.

See Also:

Constant Field Values

DATA_SEPARATOR

public static final String DATA_SEPARATOR

Separator used when joining data for signature calculation.

See Also:

Constant Field Values

Constructor Detail

HMACValidator

public HMACValidator()

Method Detail

calculateHMAC

public String calculateHMAC(String data,
                            String key)
                     throws IllegalArgumentException,
                            SignatureException

Computes the HMAC SHA-256 signature for the given data using the provided hex-encoded HMAC key.

Parameters:

data - the data to sign

key - the HMAC key in hexadecimal format

Returns:

the Base64-encoded HMAC signature

Throws:

IllegalArgumentException - if the data or key is null

SignatureException - if signature generation fails

calculateHMAC

public String calculateHMAC(NotificationRequestItem notificationRequestItem,
                            String key)
                     throws IllegalArgumentException,
                            SignatureException

Computes the HMAC SHA-256 signature for a given NotificationRequestItem.

Parameters:

notificationRequestItem - the notification to sign

key - the HMAC key in hexadecimal format

Returns:

the Base64-encoded HMAC signature

Throws:

IllegalArgumentException - if the notification item or key is invalid

SignatureException - if signature generation fails

validateHMAC

public boolean validateHMAC(String hmacSignature,
                            String hmacKey,
                            String payload)
                     throws SignatureException

Validates an HMAC signature for generic webhooks (e.g. Banking, Management).

Parameters:

hmacSignature - the signature received in the webhook

hmacKey - the configured HMAC key

payload - the payload string used for HMAC calculation

Returns:

true if the signature matches, false otherwise

Throws:

SignatureException - if validation fails

validateHMAC

public boolean validateHMAC(NotificationRequestItem notificationRequestItem,
                            String key)
                     throws IllegalArgumentException,
                            SignatureException

Validates the HMAC signature of an NotificationRequestItem.

Parameters:

notificationRequestItem - the notification containing the HMAC signature

key - the HMAC key in hexadecimal format

Returns:

true if the signature matches, false otherwise

Throws:

IllegalArgumentException - if the notification or signature is missing

SignatureException - if signature validation fails

getDataToSign

public String getDataToSign(NotificationRequestItem notificationRequestItem)
                     throws IllegalArgumentException

Builds the concatenated data string from a NotificationRequestItem to be used in HMAC signature calculation.

The data string is composed of the following fields, separated by a colon (":"):

• pspReference
• originalReference
• merchantAccountCode
• merchantReference
• amount.value
• amount.currency
• eventCode
• success

If any value is null, it is represented as an empty string in the final payload.

Parameters:

notificationRequestItem - the notification request item

Returns:

the colon-separated string of fields

Throws:

IllegalArgumentException - if the input is null