test: Add HIP-573 example

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
  - `TransactionReceipt.transactionId`
  - `TopicUpdateTransaction.[get|set]ExpirationTime()`
  - `CustomFee.[set|get]AllCollectorsAreExempt()`
+ - `ExemptCustomFeesExample`
 
 ### Fixed
  - Execute with a timeout can ignore timeout and block indefinitely in CI tests

examples/src/main/java/ExemptCustomFeesExample.java

@@ -0,0 +1,194 @@
+/*-
+ *
+ * Hedera Java SDK
+ *
+ * Copyright (C) 2020 - 2022 Hedera Hashgraph, LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+import com.hedera.hashgraph.sdk.*;
+import io.github.cdimascio.dotenv.Dotenv;
+import java8.util.Lists;
+
+import java.util.Objects;
+import java.util.concurrent.TimeoutException;
+
+/*
+    Example for HIP-573: Blanket exemptions for custom fee collectors
+    1. Create accounts A, B, and C
+    2. Create a fungible token that has three fractional fees
+    Fee #1 sends 1/100 of the transferred value to collector 0.0.A.
+    Fee #2 sends 2/100 of the transferred value to collector 0.0.B.
+    Fee #3 sends 3/100 of the transferred value to collector 0.0.C.
+    3. Collector 0.0.B sends 10_000 units of the token to 0.0.A.
+    4. Get the transaction fee for that transfer transaction
+    5. Show that the fee collector accounts in the custom fee list of the token
+    that was created was not charged a custom fee in the transfer
+*/
+public final class ExemptCustomFeesExample {
+
+    // see `.env.sample` in the repository root for how to specify these values
+    // or set environment variables with the same names
+    private static final AccountId OPERATOR_ID = AccountId.fromString(Objects.requireNonNull(Dotenv.load().get("OPERATOR_ID")));
+    private static final PrivateKey OPERATOR_KEY = PrivateKey.fromString(Objects.requireNonNull(Dotenv.load().get("OPERATOR_KEY")));
+    private static final String HEDERA_NETWORK = Dotenv.load().get("HEDERA_NETWORK", "testnet");
+
+    private ExemptCustomFeesExample() {
+    }
+
+    public static void main(String[] args) throws TimeoutException, PrecheckStatusException, ReceiptStatusException, InterruptedException {
+        Client client = Client.forName(HEDERA_NETWORK);
+        client.setOperator(OPERATOR_ID, OPERATOR_KEY);
+
+        /*
+         * Step 1
+         * Create accounts A, B, and C
+         */
+
+        PrivateKey firstAccountPrivateKey = PrivateKey.generateED25519();
+        AccountId firstAccountId = new AccountCreateTransaction()
+            .setInitialBalance(new Hbar(10))
+            .setKey(firstAccountPrivateKey)
+            .freezeWith(client)
+            .sign(firstAccountPrivateKey)
+            .execute(client)
+            .getReceipt(client)
+            .accountId;
+
+        PrivateKey secondAccountPrivateKey = PrivateKey.generateED25519();
+        AccountId secondAccountId = new AccountCreateTransaction()
+            .setInitialBalance(new Hbar(10))
+            .setKey(secondAccountPrivateKey)
+            .freezeWith(client)
+            .sign(secondAccountPrivateKey)
+            .execute(client)
+            .getReceipt(client)
+            .accountId;
+
+        PrivateKey thirdAccountPrivateKey = PrivateKey.generateED25519();
+        AccountId thirdAccountId = new AccountCreateTransaction()
+            .setInitialBalance(new Hbar(10))
+            .setKey(thirdAccountPrivateKey)
+            .freezeWith(client)
+            .sign(thirdAccountPrivateKey)
+            .execute(client)
+            .getReceipt(client)
+            .accountId;
+
+        /*
+         * Step 2
+         * 2. Create a fungible token that has three fractional fees
+         * Fee #1 sends 1/100 of the transferred value to collector 0.0.A.
+         * Fee #2 sends 2/100 of the transferred value to collector 0.0.B.
+         * Fee #3 sends 3/100 of the transferred value to collector 0.0.C.
+         */
+
+        CustomFractionalFee fee1 = new CustomFractionalFee()
+            .setFeeCollectorAccountId(firstAccountId)
+            .setNumerator(1)
+            .setDenominator(100)
+            .setAllCollectorsAreExempt(true);
+
+        CustomFractionalFee fee2 = new CustomFractionalFee()
+            .setFeeCollectorAccountId(secondAccountId)
+            .setNumerator(2)
+            .setDenominator(100)
+            .setAllCollectorsAreExempt(true);
+
+        CustomFractionalFee fee3 = new CustomFractionalFee()
+            .setFeeCollectorAccountId(thirdAccountId)
+            .setNumerator(3)
+            .setDenominator(100)
+            .setAllCollectorsAreExempt(true);
+
+        TokenCreateTransaction tokenCreateTransaction = new TokenCreateTransaction()
+            .setTokenName("HIP-573 Token")
+            .setTokenSymbol("H573")
+            .setTokenType(TokenType.FUNGIBLE_COMMON)
+            .setTreasuryAccountId(OPERATOR_ID)
+            .setAutoRenewAccountId(OPERATOR_ID)
+            .setAdminKey(OPERATOR_KEY)
+            .setFreezeKey(OPERATOR_KEY)
+            .setWipeKey(OPERATOR_KEY)
+            .setInitialSupply(100_000_000)
+            .setDecimals(2)
+            .setCustomFees(Lists.of(fee1, fee2, fee3))
+            .freezeWith(client)
+            .sign(firstAccountPrivateKey)
+            .sign(secondAccountPrivateKey)
+            .sign(thirdAccountPrivateKey);
+
+        TokenId tokenId = tokenCreateTransaction
+            .execute(client)
+            .getReceipt(client)
+            .tokenId;
+        System.out.println("TokenId: " + tokenId);
+
+        /*
+         * Step 3
+         * Collector 0.0.B sends 10_000 units of the token to 0.0.A.
+         */
+
+        // Send 10_000 units from the operator to the second account
+        new TransferTransaction()
+            .addTokenTransfer(tokenId, OPERATOR_ID, -10_000)
+            .addTokenTransfer(tokenId, secondAccountId, 10_000)
+            .freezeWith(client)
+            .sign(OPERATOR_KEY)
+            .execute(client);
+
+        TransactionResponse tokenTransferResponse = new TransferTransaction()
+            .addTokenTransfer(tokenId, secondAccountId, -10_000)
+            .addTokenTransfer(tokenId, firstAccountId, 10_000)
+            .freezeWith(client)
+            .sign(secondAccountPrivateKey)
+            .execute(client);
+
+
+        /*
+         * Step 4
+         * Get the transaction fee for that transfer transaction
+         */
+
+        Hbar transactionFee = tokenTransferResponse
+            .getRecord(client)
+            .transactionFee;
+        System.out.println("Txfee: " + transactionFee);
+
+        /*
+         * Step 5
+         * Show that the fee collector accounts in the custom fee list
+         * of the token that was created was not charged a custom fee in the transfer
+         */
+
+        Long firstAccountBalanceAfter = new AccountBalanceQuery()
+            .setAccountId(firstAccountId)
+            .execute(client)
+            .tokens.get(tokenId);
+
+        Long secondAccountBalanceAfter = new AccountBalanceQuery()
+            .setAccountId(secondAccountId)
+            .execute(client)
+            .tokens.get(tokenId);
+
+        Long thirdAccountBalanceAfter = new AccountBalanceQuery()
+            .setAccountId(thirdAccountId)
+            .execute(client)
+            .tokens.get(tokenId);
+
+        System.out.println("First account balance after TransferTransaction: " + firstAccountBalanceAfter);
+        System.out.println("Second account balance after TransferTransaction: " + secondAccountBalanceAfter);
+        System.out.println("Third account balance after TransferTransaction: " + thirdAccountBalanceAfter);
+    }
+}