Introduce test coverage for new Capital API

src/test/java/com/adyen/TransfersTest.java

@@ -49,7 +49,7 @@ public void TransactionsRetrieveTest() throws Exception {
 
   @Test
   public void TestGetCapitalAccounts() throws Exception {
-    Client client = createMockClientFromFile("mocks/capital/get-capital-account.json");
+    Client client = createMockClientFromFile("mocks/transfers/get-capital-account.json");
     CapitalApi capital = new CapitalApi(client);
     CapitalGrants response = capital.getCapitalAccount();
     assertEquals(response.getGrants().get(0).getGrantOfferId(), "string");
@@ -66,7 +66,7 @@ public void TestGetCapitalAccounts() throws Exception {
 
   @Test
   public void TestRequestGrant() throws Exception {
-    Client client = createMockClientFromFile("mocks/capital/request-grant.json");
+    Client client = createMockClientFromFile("mocks/transfers/request-grant.json");
     CapitalApi capital = new CapitalApi(client);
     CapitalGrant response = capital.requestGrantPayout(new CapitalGrantInfo());
     assertEquals(response.getGrantAccountId(), "CG00000000000000000000001");

src/test/java/com/adyen/service/capital/GrantAccountsApiTest.java

@@ -0,0 +1,65 @@
+/*
+ *                       ######
+ *                       ######
+ * ############    ####( ######  #####. ######  ############   ############
+ * #############  #####( ######  #####. ######  #############  #############
+ *        ######  #####( ######  #####. ######  #####  ######  #####  ######
+ * ###### ######  #####( ######  #####. ######  #####  #####   #####  ######
+ * ###### ######  #####( ######  #####. ######  #####          #####  ######
+ * #############  #############  #############  #############  #####  ######
+ *  ############   ############  #############   ############  #####  ######
+ *                                      ######
+ *                               #############
+ *                               ############
+ *
+ * Adyen Java API Library
+ *
+ * Copyright (c) 2026 Adyen B.V.
+ * This file is open source and available under the MIT license.
+ * See the LICENSE file for more info.
+ */
+package com.adyen.service.capital;
+
+import static org.mockito.Mockito.verify;
+
+import com.adyen.BaseTest;
+import com.adyen.Client;
+import com.adyen.constants.ApiConstants;
+import com.adyen.model.capital.GrantAccount;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class GrantAccountsApiTest extends BaseTest {
+
+  @Test
+  void testGetGrantAccount() throws Exception {
+    Client client = createMockClientFromFile("mocks/capital/get-grant-account-success.json");
+    GrantAccountsApi grantAccountsApi = new GrantAccountsApi(client);
+    GrantAccount response =
+        grantAccountsApi.getGrantAccountInformation("CG00000000000000000000001");
+
+    Assertions.assertNotNull(response);
+    Assertions.assertEquals("CG00000000000000000000001", response.getId());
+    Assertions.assertEquals("BA00000000000000000000001", response.getFundingBalanceAccountId());
+    Assertions.assertEquals(1, response.getLimits().size());
+    Assertions.assertEquals(1, response.getBalances().size());
+
+    verify(client.getHttpClient())
+        .request(
+            "https://balanceplatform-api-test.adyen.com/capital/v1/grantAccounts/CG00000000000000000000001",
+            null,
+            client.getConfig(),
+            false,
+            null,
+            ApiConstants.HttpMethod.GET,
+            null);
+  }
+
+  @Test
+  void testGetGrantAccountRequiredParams() {
+    Client client = createMockClientFromFile("mocks/capital/get-grant-account-success.json");
+    GrantAccountsApi grantAccountsApi = new GrantAccountsApi(client);
+    Assertions.assertThrows(
+        IllegalArgumentException.class, () -> grantAccountsApi.getGrantAccountInformation(null));
+  }
+}

src/test/java/com/adyen/service/capital/GrantOffersApiTest.java

@@ -0,0 +1,108 @@
+/*
+ *                       ######
+ *                       ######
+ * ############    ####( ######  #####. ######  ############   ############
+ * #############  #####( ######  #####. ######  #############  #############
+ *        ######  #####( ######  #####. ######  #####  ######  #####  ######
+ * ###### ######  #####( ######  #####. ######  #####  #####   #####  ######
+ * ###### ######  #####( ######  #####. ######  #####          #####  ######
+ * #############  #############  #############  #############  #####  ######
+ *  ############   ############  #############   ############  #####  ######
+ *                                      ######
+ *                               #############
+ *                               ############
+ *
+ * Adyen Java API Library
+ *
+ * Copyright (c) 2026 Adyen B.V.
+ * This file is open source and available under the MIT license.
+ * See the LICENSE file for more info.
+ */
+package com.adyen.service.capital;
+
+import static org.mockito.Mockito.verify;
+
+import com.adyen.BaseTest;
+import com.adyen.Client;
+import com.adyen.constants.ApiConstants;
+import com.adyen.model.capital.Amount;
+import com.adyen.model.capital.GrantOffer;
+import com.adyen.model.capital.GrantOffers;
+import java.util.Map;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class GrantOffersApiTest extends BaseTest {
+
+  @Test
+  void testGetAllGrantOffersWithQueryParam() throws Exception {
+    Client client = createMockClientFromFile("mocks/capital/grant-offers-success.json");
+    GrantOffersApi grantOffersApi = new GrantOffersApi(client);
+    GrantOffers response = grantOffersApi.getAllGrantOffers("AH00000000000000000000001", null);
+
+    Assertions.assertNotNull(response);
+    Assertions.assertEquals(1, response.getGrantOffers().size());
+    Assertions.assertEquals("GO00000000000000000000001", response.getGrantOffers().get(0).getId());
+
+    verify(client.getHttpClient())
+        .request(
+            "https://balanceplatform-api-test.adyen.com/capital/v1/grantOffers",
+            null,
+            client.getConfig(),
+            false,
+            null,
+            ApiConstants.HttpMethod.GET,
+            Map.of("accountHolderId", "AH00000000000000000000001"));
+  }
+
+  @Test
+  void testGetAllGrantOffers() throws Exception {
+    Client client = createMockClientFromFile("mocks/capital/grant-offers-success.json");
+    GrantOffersApi grantOffersApi = new GrantOffersApi(client);
+    GrantOffers response = grantOffersApi.getAllGrantOffers();
+
+    Assertions.assertNotNull(response);
+    Assertions.assertEquals(1, response.getGrantOffers().size());
+    Assertions.assertEquals("GO00000000000000000000001", response.getGrantOffers().get(0).getId());
+
+    verify(client.getHttpClient())
+        .request(
+            "https://balanceplatform-api-test.adyen.com/capital/v1/grantOffers",
+            null,
+            client.getConfig(),
+            false,
+            null,
+            ApiConstants.HttpMethod.GET,
+            Map.of());
+  }
+
+  @Test
+  void testGetGrantOffer() throws Exception {
+    Client client = createMockClientFromFile("mocks/capital/get-grant-offer-success.json");
+    GrantOffersApi grantOffersApi = new GrantOffersApi(client);
+    GrantOffer response = grantOffersApi.getGrantOffer("GO00000000000000000000001");
+
+    Assertions.assertNotNull(response);
+    Assertions.assertEquals("GO00000000000000000000001", response.getId());
+    Assertions.assertEquals("AH00000000000000000000001", response.getAccountHolderId());
+    Assertions.assertEquals(new Amount().currency("EUR").value(10000L), response.getAmount());
+
+    verify(client.getHttpClient())
+        .request(
+            "https://balanceplatform-api-test.adyen.com/capital/v1/grantOffers/GO00000000000000000000001",
+            null,
+            client.getConfig(),
+            false,
+            null,
+            ApiConstants.HttpMethod.GET,
+            null);
+  }
+
+  @Test
+  void testGetGrantOfferParams() {
+    Client client = createMockClientFromFile("mocks/capital/get-grant-offer-success.json");
+    GrantOffersApi grantOffersApi = new GrantOffersApi(client);
+    Assertions.assertThrows(
+        IllegalArgumentException.class, () -> grantOffersApi.getGrantOffer(null));
+  }
+}