SP-349 Java - Updates for POST /refunds

Author: mwarzybok-sumoheavy

src/main/java/com/bitpay/sdk/Client.java

@@ -564,6 +564,7 @@ public Invoice cancelInvoice(String invoiceId, Boolean forceCancel) throws Invoi
     public Refund createRefund(String invoiceId, Double amount, Boolean preview, Boolean immediate, Boolean buyerPaysRefundFee, String reference) throws RefundCreationException, BitPayException {
         final Map<String, Object> params = new HashMap<>();
         params.put("token", this.getAccessToken(Facade.Merchant));
+        params.put("guid", this.getGuid());
         if (invoiceId == null && amount == null) {
             throw new RefundCreationException(null ,"Invoice ID, amount and currency are required to issue a refund.");
         }

src/main/java/com/bitpay/sdk/model/Invoice/Refund.java

@@ -63,7 +63,7 @@ public Refund() {
     //
 
     /**
-     * Gets guid.
+     * Gets a variable provided by the merchant and designed to be used by the merchant to correlate the refund with a refund ID in their system.
      *
      * @return the guid
      */
@@ -74,7 +74,7 @@ public String getGuid() {
     }
 
     /**
-     * Sets guid.
+     * Sets a variable provided by the merchant and designed to be used by the merchant to correlate the refund with a refund ID in their system.
      *
      * @param guid the guid
      */