issue #133 - couple finishing touches and factory for helpers

src/main/java/io/proximax/sdk/helpers/BaseHelper.java

@@ -54,6 +54,15 @@ public BaseHelper(BlockchainApi api) {
       this.transact.setFeeCalculationStrategy(FeeCalculationStrategy.MEDIUM);
    }
 
+   /**
+    * get the blockchain API used by this helper instance
+    * 
+    * @return the API instance
+    */
+   public BlockchainApi getBlockchainApi() {
+      return api;
+   }
+
    /**
     * <b>BLOCKING!</b> announce transaction and wait for it to be added to confirmed transactions
     * 

src/main/java/io/proximax/sdk/helpers/HelperFactory.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2019 ProximaX Limited. All rights reserved.
+ * Use of this source code is governed by the Apache 2.0
+ * license that can be found in the LICENSE file.
+ */
+package io.proximax.sdk.helpers;
+
+import io.proximax.sdk.BlockchainApi;
+
+/**
+ * Factory class to simplify access to the helpers
+ */
+public class HelperFactory {
+
+   private final BlockchainApi api;
+
+   /**
+    * @param api blockchain API instance used by helpers
+    */
+   public HelperFactory(BlockchainApi api) {
+      this.api = api;
+   }
+
+   /**
+    * @return the API used by helpers
+    */
+   public BlockchainApi getBlockchainApi() {
+      return api;
+   }
+
+   /**
+    * @return helper for account related operations
+    */
+   public AccountHelper account() {
+      return new AccountHelper(api);
+   }
+
+   /**
+    * @return helper for blockchain related operations
+    */
+   public BlockchainHelper blockchain() {
+      return new BlockchainHelper(api);
+   }
+
+   /**
+    * @return helper for transfers
+    */
+   public TransferHelper transfer() {
+      return new TransferHelper(api);
+   }
+}

src/test/java/io/proximax/sdk/helpers/AccountHelperTest.java

@@ -18,12 +18,11 @@
 import org.junit.jupiter.api.Test;
 
 import io.proximax.sdk.BlockchainApi;
-import io.proximax.sdk.helpers.AccountHelper;
 import io.proximax.sdk.model.account.Account;
 import io.proximax.sdk.model.blockchain.NetworkType;
 
 /**
- * TODO add proper description
+ * {@link AccountHelper} tests
  */
 class AccountHelperTest {
    private BlockchainApi api;

src/test/java/io/proximax/sdk/helpers/HelperFactoryTest.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2019 ProximaX Limited. All rights reserved.
+ * Use of this source code is governed by the Apache 2.0
+ * license that can be found in the LICENSE file.
+ */
+package io.proximax.sdk.helpers;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+import io.proximax.sdk.BlockchainApi;
+import io.proximax.sdk.model.transaction.builder.TransactionBuilderFactory;
+
+/**
+ * {@link HelperFactory} tests
+ */
+class HelperFactoryTest {
+
+   @Test
+   void testConstructor() {
+      BlockchainApi api = Mockito.mock(BlockchainApi.class);
+      assertEquals(api, new HelperFactory(api).getBlockchainApi());
+   }
+
+   @Test
+   void testFacMethods() {
+      BlockchainApi api = Mockito.mock(BlockchainApi.class);
+      TransactionBuilderFactory transact = Mockito.mock(TransactionBuilderFactory.class);
+
+      Mockito.when(api.transact()).thenReturn(transact);
+
+      HelperFactory fac = new HelperFactory(api);
+      // make sure that API is passed to the helpers
+      assertEquals(api, fac.account().getBlockchainApi());
+      assertEquals(api, fac.blockchain().getBlockchainApi());
+      assertEquals(api, fac.transfer().getBlockchainApi());
+   }
+}