Sample.java

// ### Create Patch Request
		List<Patch> patchRequest = new ArrayList<Patch>();

		// ### Amount
		// Let's update the payment amount as an example.
		Amount amount = new Amount();
		amount.setCurrency("USD");
		// Total must be equal to sum of shipping, tax and subtotal.
		amount.setTotal("17.50");
		amount.setDetails(new Details().setShipping("11.50").setTax("1")
				.setSubtotal("5"));

		// ### Patch Object
		// Create a patch object, and fill these 3 properties accordingly.
		Patch patch1 = new Patch();
		patch1.setOp("replace").setPath("/transactions/0/amount").setValue(amount);
		patchRequest.add(patch1);

		try {
			// ### Api Context
			// Pass in a `ApiContext` object to authenticate
			// the call and to send a unique request id
			// (that ensures idempotency). The SDK generates
			// a request id if you do not pass one explicitly.
			APIContext apiContext = new APIContext(clientID, clientSecret, mode);

			// Create a payment by posting to the APIService
			// using a valid AccessToken
			// The return object contains the status;
			payment.update(apiContext, patchRequest);

			LOGGER.info("Updated Payment with " + payment.getId());
			return true;
		} catch (PayPalRESTException e) {
			System.out.println(e.getDetails());
		}