Setup kotlin examples

kotlin-example/src/main/kotlin/org/onflow/examples/kotlin/getAccountBalance/GetAccountBalanceAccessAPIConnector.kt

@@ -2,20 +2,18 @@ package org.onflow.examples.kotlin.getAccountBalance
 
 import org.onflow.flow.sdk.*
 
-internal class GetBalanceAccessAPIConnector(
+internal class GetAccountBalanceAccessAPIConnector(
     private val accessAPI: FlowAccessApi
 ) {
-    fun getBalanceAtLatestBlock(address: FlowAddress): Long {
-        return when (val response = accessAPI.getAccountBalanceAtLatestBlock(address)) {
+    fun getBalanceAtLatestBlock(address: FlowAddress): Long =
+        when (val response = accessAPI.getAccountBalanceAtLatestBlock(address)) {
             is FlowAccessApi.AccessApiCallResponse.Success -> response.data
             is FlowAccessApi.AccessApiCallResponse.Error -> throw Exception(response.message, response.throwable)
         }
-    }
 
-    fun getBalanceAtBlockHeight(address: FlowAddress, height: Long): Long {
-        return when (val response = accessAPI.getAccountBalanceAtBlockHeight(address, height)) {
+    fun getBalanceAtBlockHeight(address: FlowAddress, height: Long): Long =
+        when (val response = accessAPI.getAccountBalanceAtBlockHeight(address, height)) {
             is FlowAccessApi.AccessApiCallResponse.Success -> response.data
             is FlowAccessApi.AccessApiCallResponse.Error -> throw Exception(response.message, response.throwable)
         }
-    }
 }

kotlin-example/src/test/kotlin/org/onflow/examples/kotlin/getAccountBalance/GetAccountBalanceAccessAPIConnectorTest.kt

@@ -0,0 +1,73 @@
+package org.onflow.examples.kotlin.getAccountBalance
+
+import org.junit.jupiter.api.Assertions
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Test
+import org.onflow.flow.common.test.FlowEmulatorProjectTest
+import org.onflow.flow.common.test.FlowServiceAccountCredentials
+import org.onflow.flow.common.test.FlowTestClient
+import org.onflow.flow.common.test.TestAccount
+import org.onflow.flow.sdk.FlowAccessApi
+
+@FlowEmulatorProjectTest(flowJsonLocation = "../flow/flow.json")
+internal class GetAccountBalanceAccessAPIConnectorTest {
+    @FlowServiceAccountCredentials
+    lateinit var serviceAccount: TestAccount
+
+    @FlowTestClient
+    lateinit var accessAPI: FlowAccessApi
+
+    private lateinit var balanceAPIConnector: GetAccountBalanceAccessAPIConnector
+
+    @BeforeEach
+    fun setup() {
+        balanceAPIConnector = GetAccountBalanceAccessAPIConnector(accessAPI)
+    }
+
+    @Test
+    fun `Can fetch account balance at the latest block`() {
+        val address = serviceAccount.flowAddress
+        val balance = balanceAPIConnector.getBalanceAtLatestBlock(address)
+
+        Assertions.assertNotNull(balance, "Balance should not be null")
+        Assertions.assertTrue(balance >= 0, "Balance should be non-negative")
+    }
+
+    @Test
+    fun `Can fetch account balance at a specific block height`() {
+        val address = serviceAccount.flowAddress
+        val latestBlock = accessAPI.getLatestBlock(true) // Fetch the latest sealed block
+
+        when (latestBlock) {
+            is FlowAccessApi.AccessApiCallResponse.Success -> {
+                val balanceAtHeight = balanceAPIConnector.getBalanceAtBlockHeight(address, latestBlock.data.height)
+
+                Assertions.assertNotNull(balanceAtHeight, "Balance at specific block height should not be null")
+                Assertions.assertTrue(balanceAtHeight >= 0, "Balance at specific block height should be non-negative")
+            }
+            is FlowAccessApi.AccessApiCallResponse.Error -> Assertions.fail("Failed to retrieve the latest block: ${latestBlock.message}")
+        }
+    }
+
+    @Test
+    fun `Balances at the latest block and specific block height should match`() {
+        val address = serviceAccount.flowAddress
+
+        // Fetch balance at latest block
+        val balanceAtLatest = balanceAPIConnector.getBalanceAtLatestBlock(address)
+
+        // Fetch latest block height
+        val latestBlock = accessAPI.getLatestBlock(true)
+        when (latestBlock) {
+            is FlowAccessApi.AccessApiCallResponse.Success -> {
+                val blockHeight = latestBlock.data.height
+
+                // Fetch balance at the same block height
+                val balanceAtHeight = balanceAPIConnector.getBalanceAtBlockHeight(address, blockHeight)
+
+                Assertions.assertEquals(balanceAtLatest, balanceAtHeight, "Balance at latest block and specific block height should match")
+            }
+            is FlowAccessApi.AccessApiCallResponse.Error -> Assertions.fail("Failed to retrieve the latest block: ${latestBlock.message}")
+        }
+    }
+}