From 2ad4b7ab47e1e76b5052311afa67a9be4b107571 Mon Sep 17 00:00:00 2001
From: Vera Kobylchak <vera@temporal.io>
Date: Wed, 18 Aug 2021 14:53:10 -0700
Subject: [PATCH 1/6] Added getMemo to Workflow

---
 .../replay/ReplayWorkflowContext.java         |  8 ++
 .../replay/ReplayWorkflowContextImpl.java     |  6 ++
 .../internal/replay/WorkflowContext.java      |  4 +
 .../internal/sync/WorkflowInternal.java       |  5 +
 .../java/io/temporal/workflow/Workflow.java   |  5 +
 .../internal/testing/WorkflowTestingTest.java |  2 +-
 .../java/io/temporal/workflow/MemoTest.java   | 91 ++++++++++++-------
 .../sync/DummySyncWorkflowContext.java        |  6 ++
 8 files changed, 95 insertions(+), 32 deletions(-)

diff --git a/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java b/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java
index 587fd33566..9f0e96311c 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java
@@ -22,6 +22,7 @@
 import com.uber.m3.tally.Scope;
 import io.temporal.api.command.v1.ContinueAsNewWorkflowExecutionCommandAttributes;
 import io.temporal.api.command.v1.SignalExternalWorkflowExecutionCommandAttributes;
+import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.Payloads;
 import io.temporal.api.common.v1.SearchAttributes;
 import io.temporal.api.common.v1.WorkflowExecution;
@@ -94,6 +95,13 @@ public interface ReplayWorkflowContext extends ReplayAware {
 
   Duration getWorkflowTaskTimeout();
 
+  /**
+   * Used to retrieve the memo.
+   *
+   * @return Memo object
+   */
+  Payload getMemo(String key);
+
   /**
    * Used to retrieve search attributes.
    *
diff --git a/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContextImpl.java b/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContextImpl.java
index 690d6c4433..62c9cc54aa 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContextImpl.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContextImpl.java
@@ -25,6 +25,7 @@
 import io.temporal.api.command.v1.ScheduleActivityTaskCommandAttributes;
 import io.temporal.api.command.v1.SignalExternalWorkflowExecutionCommandAttributes;
 import io.temporal.api.command.v1.StartTimerCommandAttributes;
+import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.Payloads;
 import io.temporal.api.common.v1.SearchAttributes;
 import io.temporal.api.common.v1.WorkflowExecution;
@@ -191,6 +192,11 @@ public long getWorkflowExecutionExpirationTimestampMillis() {
     return workflowContext.getWorkflowExecutionExpirationTimestampMillis();
   }
 
+  @Override
+  public Payload getMemo(String key) {
+    return workflowContext.getMemo(key);
+  }
+
   @Override
   public SearchAttributes getSearchAttributes() {
     return workflowContext.getSearchAttributes();
diff --git a/temporal-sdk/src/main/java/io/temporal/internal/replay/WorkflowContext.java b/temporal-sdk/src/main/java/io/temporal/internal/replay/WorkflowContext.java
index 7613233fc8..91fbf37c89 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/replay/WorkflowContext.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/replay/WorkflowContext.java
@@ -149,6 +149,10 @@ public Map<String, Payload> getHeader() {
     return startedAttributes.getHeader().getFieldsMap();
   }
 
+  public Payload getMemo(String key) {
+    return startedAttributes.getMemo().getFieldsMap().get(key);
+  }
+
   SearchAttributes getSearchAttributes() {
     return searchAttributes == null || searchAttributes.getIndexedFieldsCount() == 0
         ? null
diff --git a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
index 6dd5bf87b5..d34a3eecf0 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
@@ -25,6 +25,7 @@
 import com.uber.m3.tally.Scope;
 import io.temporal.activity.ActivityOptions;
 import io.temporal.activity.LocalActivityOptions;
+import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.WorkflowExecution;
 import io.temporal.common.RetryOptions;
 import io.temporal.common.converter.DataConverter;
@@ -428,6 +429,10 @@ public static WorkflowInfo getWorkflowInfo() {
     return new WorkflowInfoImpl(getRootWorkflowContext().getContext());
   }
 
+  public static Payload getMemo(String key) {
+    return getRootWorkflowContext().getContext().getMemo(key);
+  }
+
   public static <R> R retry(
       RetryOptions options, Optional<Duration> expiration, Functions.Func<R> fn) {
     return WorkflowRetryerInternal.validateOptionsAndRetry(options, expiration, fn);
diff --git a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
index 0a4cf87d4f..4f6ed19ece 100644
--- a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
+++ b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
@@ -22,6 +22,7 @@
 import com.uber.m3.tally.Scope;
 import io.temporal.activity.ActivityOptions;
 import io.temporal.activity.LocalActivityOptions;
+import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.WorkflowExecution;
 import io.temporal.common.RetryOptions;
 import io.temporal.failure.ActivityFailure;
@@ -615,6 +616,10 @@ public static WorkflowInfo getInfo() {
     return WorkflowInternal.getWorkflowInfo();
   }
 
+  public static Payload getMemo(String key) {
+    return WorkflowInternal.getMemo(key);
+  }
+
   /**
    * Wraps the Runnable method argument in a {@link CancellationScope}. The {@link
    * CancellationScope#run()} calls {@link Runnable#run()} on the wrapped Runnable. The returned
diff --git a/temporal-sdk/src/test/java/io/temporal/internal/testing/WorkflowTestingTest.java b/temporal-sdk/src/test/java/io/temporal/internal/testing/WorkflowTestingTest.java
index 3b57cb47da..536aa5e039 100644
--- a/temporal-sdk/src/test/java/io/temporal/internal/testing/WorkflowTestingTest.java
+++ b/temporal-sdk/src/test/java/io/temporal/internal/testing/WorkflowTestingTest.java
@@ -204,7 +204,7 @@ public void testActivitySimulatedTimeout() {
     TestWorkflow1 workflow = client.newWorkflowStub(TestWorkflow1.class, options);
     try {
       workflow.execute("input1");
-      fail("unreacheable");
+      fail("unreachable");
     } catch (WorkflowException e) {
       assertTrue(e.getCause() instanceof ActivityFailure);
       TimeoutFailure te = (TimeoutFailure) e.getCause().getCause();
diff --git a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
index 98902a3ccc..5c5f888f4e 100644
--- a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
+++ b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
@@ -19,8 +19,12 @@
 
 package io.temporal.workflow;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
 import com.google.protobuf.ByteString;
 import com.uber.m3.tally.NoopScope;
+import com.uber.m3.util.ImmutableMap;
 import io.temporal.api.common.v1.Memo;
 import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.WorkflowExecution;
@@ -34,50 +38,75 @@
 import io.temporal.testing.internal.SDKTestWorkflowRule;
 import io.temporal.workflow.shared.TestMultiArgWorkflowFunctions.TestMultiArgWorkflowImpl;
 import io.temporal.workflow.shared.TestMultiArgWorkflowFunctions.TestNoArgsWorkflowFunc;
-import java.util.HashMap;
+import io.temporal.workflow.shared.TestWorkflows.NoArgsWorkflow;
 import java.util.Map;
-import org.junit.Assert;
 import org.junit.Rule;
 import org.junit.Test;
 
 public class MemoTest {
 
+  private static final String MEMO_KEY = "testKey";
+  private static final String MEMO_VALUE = "testValue";
+  private static final Map<String, Object> MEMO = ImmutableMap.of(MEMO_KEY, MEMO_VALUE);
+
   @Rule
   public SDKTestWorkflowRule testWorkflowRule =
-      SDKTestWorkflowRule.newBuilder().setWorkflowTypes(TestMultiArgWorkflowImpl.class).build();
+      SDKTestWorkflowRule.newBuilder()
+          .setWorkflowTypes(TestMultiArgWorkflowImpl.class, WorkflowImpl.class)
+          .build();
 
   @Test
   public void testMemo() {
-    if (testWorkflowRule.getTestEnvironment() != null) {
-      String testMemoKey = "testKey";
-      String testMemoValue = "testValue";
-      Map<String, Object> memo = new HashMap<String, Object>();
-      memo.put(testMemoKey, testMemoValue);
+    if (testWorkflowRule.getTestEnvironment() == null) {
+      return;
+    }
+
+    WorkflowOptions workflowOptions =
+        SDKTestOptions.newWorkflowOptionsWithTimeouts(testWorkflowRule.getTaskQueue())
+            .toBuilder()
+            .setTaskQueue(testWorkflowRule.getTaskQueue())
+            .setMemo(MEMO)
+            .build();
+
+    TestNoArgsWorkflowFunc stubF =
+        testWorkflowRule
+            .getWorkflowClient()
+            .newWorkflowStub(TestNoArgsWorkflowFunc.class, workflowOptions);
+    WorkflowExecution executionF = WorkflowClient.start(stubF::func);
 
-      WorkflowOptions workflowOptions =
-          SDKTestOptions.newWorkflowOptionsWithTimeouts(testWorkflowRule.getTaskQueue())
-              .toBuilder()
-              .setMemo(memo)
-              .build();
-      TestNoArgsWorkflowFunc stubF =
-          testWorkflowRule
-              .getWorkflowClient()
-              .newWorkflowStub(TestNoArgsWorkflowFunc.class, workflowOptions);
-      WorkflowExecution executionF = WorkflowClient.start(stubF::func);
+    GetWorkflowExecutionHistoryResponse historyResp =
+        WorkflowExecutionUtils.getHistoryPage(
+            testWorkflowRule.getTestEnvironment().getWorkflowService(),
+            SDKTestWorkflowRule.NAMESPACE,
+            executionF,
+            ByteString.EMPTY,
+            new NoopScope());
+    HistoryEvent startEvent = historyResp.getHistory().getEvents(0);
+    Memo memoFromEvent = startEvent.getWorkflowExecutionStartedEventAttributes().getMemo();
+    Payload memoBytes = memoFromEvent.getFieldsMap().get(MEMO_KEY);
+    String memoRetrieved =
+        GsonJsonPayloadConverter.getInstance().fromData(memoBytes, String.class, String.class);
+    assertEquals(MEMO_VALUE, memoRetrieved);
+  }
+
+  @Test
+  public void testMemoInWorkflow() {
+    WorkflowOptions workflowOptions =
+        SDKTestOptions.newWorkflowOptionsWithTimeouts(testWorkflowRule.getTaskQueue())
+            .toBuilder()
+            .setTaskQueue(testWorkflowRule.getTaskQueue())
+            .setMemo(MEMO)
+            .build();
+
+    NoArgsWorkflow workflow =
+        testWorkflowRule.getWorkflowClient().newWorkflowStub(NoArgsWorkflow.class, workflowOptions);
+    workflow.execute();
+  }
 
-      GetWorkflowExecutionHistoryResponse historyResp =
-          WorkflowExecutionUtils.getHistoryPage(
-              testWorkflowRule.getTestEnvironment().getWorkflowService(),
-              SDKTestWorkflowRule.NAMESPACE,
-              executionF,
-              ByteString.EMPTY,
-              new NoopScope());
-      HistoryEvent startEvent = historyResp.getHistory().getEvents(0);
-      Memo memoFromEvent = startEvent.getWorkflowExecutionStartedEventAttributes().getMemo();
-      Payload memoBytes = memoFromEvent.getFieldsMap().get(testMemoKey);
-      String memoRetrieved =
-          GsonJsonPayloadConverter.getInstance().fromData(memoBytes, String.class, String.class);
-      Assert.assertEquals(testMemoValue, memoRetrieved);
+  public static class WorkflowImpl implements NoArgsWorkflow {
+    @Override
+    public void execute() {
+      assertNotNull(Workflow.getMemo(MEMO_KEY));
     }
   }
 }
diff --git a/temporal-testing/src/main/java/io/temporal/internal/sync/DummySyncWorkflowContext.java b/temporal-testing/src/main/java/io/temporal/internal/sync/DummySyncWorkflowContext.java
index 5e0c7d1daa..2a56ad2ca5 100644
--- a/temporal-testing/src/main/java/io/temporal/internal/sync/DummySyncWorkflowContext.java
+++ b/temporal-testing/src/main/java/io/temporal/internal/sync/DummySyncWorkflowContext.java
@@ -23,6 +23,7 @@
 import com.uber.m3.tally.Scope;
 import io.temporal.api.command.v1.ContinueAsNewWorkflowExecutionCommandAttributes;
 import io.temporal.api.command.v1.SignalExternalWorkflowExecutionCommandAttributes;
+import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.Payloads;
 import io.temporal.api.common.v1.SearchAttributes;
 import io.temporal.api.common.v1.WorkflowExecution;
@@ -141,6 +142,11 @@ public Duration getWorkflowTaskTimeout() {
       throw new UnsupportedOperationException("not implemented");
     }
 
+    @Override
+    public Payload getMemo(String key) {
+      throw new UnsupportedOperationException("not implemented");
+    }
+
     @Override
     public SearchAttributes getSearchAttributes() {
       throw new UnsupportedOperationException("not implemented");

From e5d3824ab198f5708a97bc2d552091a4da218b2d Mon Sep 17 00:00:00 2001
From: Vera Kobylchak <vera@temporal.io>
Date: Thu, 19 Aug 2021 12:21:26 -0700
Subject: [PATCH 2/6] Memo getter returns object

---
 .../internal/sync/WorkflowInternal.java       |  5 +++--
 .../java/io/temporal/workflow/Workflow.java   |  9 +++++---
 .../java/io/temporal/workflow/MemoTest.java   | 21 ++++++++++++++++---
 3 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
index d34a3eecf0..4d8fdcabdb 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
@@ -429,8 +429,9 @@ public static WorkflowInfo getWorkflowInfo() {
     return new WorkflowInfoImpl(getRootWorkflowContext().getContext());
   }
 
-  public static Payload getMemo(String key) {
-    return getRootWorkflowContext().getContext().getMemo(key);
+  public static <T> T getMemo(String key, Class<T> valueClass, Type valueType) {
+    Payload memo = getRootWorkflowContext().getContext().getMemo(key);
+    return DataConverter.getDefaultInstance().fromPayload(memo, valueClass, valueType);
   }
 
   public static <R> R retry(
diff --git a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
index 4f6ed19ece..d861453fe2 100644
--- a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
+++ b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
@@ -22,7 +22,6 @@
 import com.uber.m3.tally.Scope;
 import io.temporal.activity.ActivityOptions;
 import io.temporal.activity.LocalActivityOptions;
-import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.WorkflowExecution;
 import io.temporal.common.RetryOptions;
 import io.temporal.failure.ActivityFailure;
@@ -616,8 +615,12 @@ public static WorkflowInfo getInfo() {
     return WorkflowInternal.getWorkflowInfo();
   }
 
-  public static Payload getMemo(String key) {
-    return WorkflowInternal.getMemo(key);
+  public static Object getMemo(String key, Type valueType) {
+    return getMemo(key, valueType.getClass(), valueType);
+  }
+
+  public static <T> T getMemo(String key, Class<T> valueClass, Type valueType) {
+    return WorkflowInternal.getMemo(key, valueClass, valueType);
   }
 
   /**
diff --git a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
index 5c5f888f4e..6d347f866e 100644
--- a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
+++ b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
@@ -20,7 +20,7 @@
 package io.temporal.workflow;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 
 import com.google.protobuf.ByteString;
 import com.uber.m3.tally.NoopScope;
@@ -39,6 +39,7 @@
 import io.temporal.workflow.shared.TestMultiArgWorkflowFunctions.TestMultiArgWorkflowImpl;
 import io.temporal.workflow.shared.TestMultiArgWorkflowFunctions.TestNoArgsWorkflowFunc;
 import io.temporal.workflow.shared.TestWorkflows.NoArgsWorkflow;
+import java.util.HashMap;
 import java.util.Map;
 import org.junit.Rule;
 import org.junit.Test;
@@ -47,7 +48,18 @@ public class MemoTest {
 
   private static final String MEMO_KEY = "testKey";
   private static final String MEMO_VALUE = "testValue";
-  private static final Map<String, Object> MEMO = ImmutableMap.of(MEMO_KEY, MEMO_VALUE);
+  private static final String MEMO_KEY_2 = "testKey2";
+  private static final Integer MEMO_VALUE_2 = 1;
+  private static final Map<String, Object> MEMO =
+      ImmutableMap.of(
+          MEMO_KEY,
+          MEMO_VALUE,
+          MEMO_KEY_2,
+          new HashMap<String, Integer>() {
+            {
+              put(MEMO_KEY_2, MEMO_VALUE_2);
+            }
+          });
 
   @Rule
   public SDKTestWorkflowRule testWorkflowRule =
@@ -106,7 +118,10 @@ public void testMemoInWorkflow() {
   public static class WorkflowImpl implements NoArgsWorkflow {
     @Override
     public void execute() {
-      assertNotNull(Workflow.getMemo(MEMO_KEY));
+      assertEquals(MEMO_VALUE, Workflow.getMemo(MEMO_KEY, String.class));
+      Map result = Workflow.getMemo(MEMO_KEY_2, Map.class, HashMap.class);
+      assertTrue(result instanceof HashMap);
+      assertEquals(MEMO_VALUE_2, result.get(MEMO_KEY_2));
     }
   }
 }

From c2f3e5254c36899b2a93e227bedd3ae5ffe598b4 Mon Sep 17 00:00:00 2001
From: Vera Kobylchak <vera@temporal.io>
Date: Thu, 19 Aug 2021 13:26:22 -0700
Subject: [PATCH 3/6] Mixed up class and type

---
 .../src/main/java/io/temporal/workflow/Workflow.java         | 4 ++--
 .../src/test/java/io/temporal/workflow/MemoTest.java         | 5 ++++-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
index d861453fe2..13cdb57951 100644
--- a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
+++ b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
@@ -615,8 +615,8 @@ public static WorkflowInfo getInfo() {
     return WorkflowInternal.getWorkflowInfo();
   }
 
-  public static Object getMemo(String key, Type valueType) {
-    return getMemo(key, valueType.getClass(), valueType);
+  public static <T> Object getMemo(String key, Class<T> valueClass) {
+    return getMemo(key, valueClass, valueClass.getGenericSuperclass());
   }
 
   public static <T> T getMemo(String key, Class<T> valueClass, Type valueType) {
diff --git a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
index 6d347f866e..c1c58879e6 100644
--- a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
+++ b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
@@ -22,6 +22,7 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
+import com.google.common.reflect.TypeToken;
 import com.google.protobuf.ByteString;
 import com.uber.m3.tally.NoopScope;
 import com.uber.m3.util.ImmutableMap;
@@ -119,7 +120,9 @@ public static class WorkflowImpl implements NoArgsWorkflow {
     @Override
     public void execute() {
       assertEquals(MEMO_VALUE, Workflow.getMemo(MEMO_KEY, String.class));
-      Map result = Workflow.getMemo(MEMO_KEY_2, Map.class, HashMap.class);
+      Map result =
+          Workflow.getMemo(
+              MEMO_KEY_2, Map.class, new TypeToken<HashMap<String, Integer>>() {}.getType());
       assertTrue(result instanceof HashMap);
       assertEquals(MEMO_VALUE_2, result.get(MEMO_KEY_2));
     }

From 444cb78fb00348adcbce4ff8510fd35bc71a68e9 Mon Sep 17 00:00:00 2001
From: Vera Kobylchak <vera@temporal.io>
Date: Thu, 19 Aug 2021 12:21:26 -0700
Subject: [PATCH 4/6] Memo getter returns object

---
 .../internal/sync/WorkflowInternal.java       |  5 ++-
 .../java/io/temporal/workflow/Workflow.java   | 45 ++++++++++---------
 .../java/io/temporal/workflow/MemoTest.java   | 24 ++++++++--
 3 files changed, 47 insertions(+), 27 deletions(-)

diff --git a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
index d34a3eecf0..4d8fdcabdb 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
@@ -429,8 +429,9 @@ public static WorkflowInfo getWorkflowInfo() {
     return new WorkflowInfoImpl(getRootWorkflowContext().getContext());
   }
 
-  public static Payload getMemo(String key) {
-    return getRootWorkflowContext().getContext().getMemo(key);
+  public static <T> T getMemo(String key, Class<T> valueClass, Type valueType) {
+    Payload memo = getRootWorkflowContext().getContext().getMemo(key);
+    return DataConverter.getDefaultInstance().fromPayload(memo, valueClass, valueType);
   }
 
   public static <R> R retry(
diff --git a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
index 4f6ed19ece..c594b09f5e 100644
--- a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
+++ b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
@@ -22,7 +22,6 @@
 import com.uber.m3.tally.Scope;
 import io.temporal.activity.ActivityOptions;
 import io.temporal.activity.LocalActivityOptions;
-import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.WorkflowExecution;
 import io.temporal.common.RetryOptions;
 import io.temporal.failure.ActivityFailure;
@@ -335,7 +334,7 @@
  * <ul>
  *   <li>Do not use any mutable global variables because multiple instances of workflows are
  *       executed in parallel.
- *   <li>Do not call any non deterministic functions like non seeded random or {@link
+ *   <li>Do not call any non-deterministic functions like non seeded random or {@link
  *       UUID#randomUUID()} directly form the workflow code. Always do this in activities.
  *   <li>Don’t perform any IO or service calls as they are not usually deterministic. Use activities
  *       for this.
@@ -616,8 +615,12 @@ public static WorkflowInfo getInfo() {
     return WorkflowInternal.getWorkflowInfo();
   }
 
-  public static Payload getMemo(String key) {
-    return WorkflowInternal.getMemo(key);
+  public static <T> Object getMemo(String key, Class<T> valueClass) {
+    return getMemo(key, valueClass, valueClass.getGenericSuperclass());
+  }
+
+  public static <T> T getMemo(String key, Class<T> valueClass, Type valueType) {
+    return WorkflowInternal.getMemo(key, valueClass, valueType);
   }
 
   /**
@@ -630,12 +633,11 @@ public static Payload getMemo(String key) {
    * canceled and a {@link Promise} that contains their result will throw {@link CanceledFailure}
    * when {@link Promise#get()} is called.
    *
-   * <p>The new cancellation scope is linked to the parent one (available as {@link
-   * CancellationScope#current()}. If the parent one is canceled then all the children scopes are
-   * canceled automatically. The main workflow function (annotated with @{@link WorkflowMethod} is
-   * wrapped within a root cancellation scope which gets canceled when a workflow is canceled
-   * through the Temporal CancelWorkflowExecution API. To perform cleanup operations that require
-   * blocking after the current scope is canceled use a scope created through {@link
+   * <p>The new cancellation scope {@link CancellationScope#current()} is linked to the parent one.
+   * If the parent one is canceled then all the children scopes are wrapped within a root
+   * cancellation scope which gets canceled when a workflow is canceled through the Temporal
+   * CancelWorkflowExecution API. To perform cleanup operations that require blocking after the
+   * current scope is canceled use a scope created through {@link
    * #newDetachedCancellationScope(Runnable)}.
    *
    * <p>Example of running activities in parallel and cancelling them after a specified timeout.
@@ -692,10 +694,10 @@ public static CancellationScope newCancellationScope(Functions.Proc1<Cancellatio
   }
 
   /**
-   * Creates a CancellationScope that is not linked to a parent scope. {@link
-   * CancellationScope#run()} must be called to execute the code the scope wraps. The detached scope
-   * is needed to execute cleanup code after a workflow is canceled which cancels the root scope
-   * that wraps the @WorkflowMethod invocation. Here is an example usage:
+   * Creates a CancellationScope {@link CancellationScope#run()} that is not linked to a parent
+   * scope must be called to execute the code the scope wraps. The detached scope is needed to
+   * execute cleanup code after a workflow is canceled which cancels the root scope that wraps
+   * the @WorkflowMethod invocation. Here is an example usage:
    *
    * <pre><code>
    *  try {
@@ -845,8 +847,7 @@ public static <R> R retry(
 
   /**
    * Invokes function retrying in case of failures according to retry options. Synchronous variant.
-   * Use {@link Async#retry(RetryOptions, Optional, Functions.Func)} (RetryOptions, Optional, Func)}
-   * for asynchronous functions.
+   * Use {@link Async#retry(RetryOptions, Optional, Functions.Func)} for asynchronous functions.
    *
    * @param options retry options that specify retry policy
    * @param expiration if specified stop retrying after this interval
@@ -900,7 +901,7 @@ public static RuntimeException wrap(Exception e) {
    * Replay safe way to generate UUID.
    *
    * <p>Must be used instead of {@link UUID#randomUUID()} which relies on a random generator, thus
-   * leads to non deterministic code which is prohibited inside a workflow.
+   * leads to non-deterministic code which is prohibited inside a workflow.
    */
   public static UUID randomUUID() {
     return WorkflowInternal.randomUUID();
@@ -950,7 +951,7 @@ public static boolean isReplaying() {
    * </code></pre>
    *
    * On replay the provided function is not executed, the random will always be 0, and the workflow
-   * could takes a different path breaking the determinism.
+   * could take a different path breaking the determinism.
    *
    * <p>Here is the correct way to use sideEffect:
    *
@@ -1004,7 +1005,7 @@ public static <R> R sideEffect(Class<R> resultClass, Func<R> func) {
    * </code></pre>
    *
    * On replay the provided function is not executed, the random will always be 0, and the workflow
-   * could takes a different path breaking the determinism.
+   * could take a different path breaking the determinism.
    *
    * <p>Here is the correct way to use sideEffect:
    *
@@ -1057,7 +1058,7 @@ public static <R> R sideEffect(Class<R> resultClass, Type resultType, Func<R> fu
    *     if call to updated with stored and a new value as arguments returns true. It is not called
    *     for the first value.
    * @param resultClass class of the side effect
-   * @param func function that produces a value. This function can contain non deterministic code.
+   * @param func function that produces a value. This function can contain non-deterministic code.
    * @see #sideEffect(Class, Functions.Func)
    */
   public static <R> R mutableSideEffect(
@@ -1092,7 +1093,7 @@ public static <R> R mutableSideEffect(
    *     for the first value.
    * @param resultClass class of the side effect
    * @param resultType type of the side effect. Differs from resultClass for generic types.
-   * @param func function that produces a value. This function can contain non deterministic code.
+   * @param func function that produces a value. This function can contain non-deterministic code.
    * @see #sideEffect(Class, Functions.Func)
    */
   public static <R> R mutableSideEffect(
@@ -1193,7 +1194,7 @@ public static int getVersion(String changeId, int minSupported, int maxSupported
 
   /**
    * Get scope for reporting business metrics in workflow logic. This should be used instead of
-   * creating new metrics scopes as it is able to dedup metrics during replay.
+   * creating new metrics scopes as it is able to dedupe metrics during replay.
    *
    * <p>The original metrics scope is set through {@link WorkerOptions} when a worker starts up.
    */
diff --git a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
index 5c5f888f4e..c1c58879e6 100644
--- a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
+++ b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
@@ -20,8 +20,9 @@
 package io.temporal.workflow;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 
+import com.google.common.reflect.TypeToken;
 import com.google.protobuf.ByteString;
 import com.uber.m3.tally.NoopScope;
 import com.uber.m3.util.ImmutableMap;
@@ -39,6 +40,7 @@
 import io.temporal.workflow.shared.TestMultiArgWorkflowFunctions.TestMultiArgWorkflowImpl;
 import io.temporal.workflow.shared.TestMultiArgWorkflowFunctions.TestNoArgsWorkflowFunc;
 import io.temporal.workflow.shared.TestWorkflows.NoArgsWorkflow;
+import java.util.HashMap;
 import java.util.Map;
 import org.junit.Rule;
 import org.junit.Test;
@@ -47,7 +49,18 @@ public class MemoTest {
 
   private static final String MEMO_KEY = "testKey";
   private static final String MEMO_VALUE = "testValue";
-  private static final Map<String, Object> MEMO = ImmutableMap.of(MEMO_KEY, MEMO_VALUE);
+  private static final String MEMO_KEY_2 = "testKey2";
+  private static final Integer MEMO_VALUE_2 = 1;
+  private static final Map<String, Object> MEMO =
+      ImmutableMap.of(
+          MEMO_KEY,
+          MEMO_VALUE,
+          MEMO_KEY_2,
+          new HashMap<String, Integer>() {
+            {
+              put(MEMO_KEY_2, MEMO_VALUE_2);
+            }
+          });
 
   @Rule
   public SDKTestWorkflowRule testWorkflowRule =
@@ -106,7 +119,12 @@ public void testMemoInWorkflow() {
   public static class WorkflowImpl implements NoArgsWorkflow {
     @Override
     public void execute() {
-      assertNotNull(Workflow.getMemo(MEMO_KEY));
+      assertEquals(MEMO_VALUE, Workflow.getMemo(MEMO_KEY, String.class));
+      Map result =
+          Workflow.getMemo(
+              MEMO_KEY_2, Map.class, new TypeToken<HashMap<String, Integer>>() {}.getType());
+      assertTrue(result instanceof HashMap);
+      assertEquals(MEMO_VALUE_2, result.get(MEMO_KEY_2));
     }
   }
 }

From 11e3afc2ad95e5bd4e03ea0391984193d185fc47 Mon Sep 17 00:00:00 2001
From: Vera Kobylchak <vera@temporal.io>
Date: Tue, 24 Aug 2021 23:33:40 -0700
Subject: [PATCH 5/6] Adde javadocs

---
 .../internal/sync/WorkflowInternal.java       |  2 +-
 .../java/io/temporal/workflow/Workflow.java   | 26 ++++++++++++++++---
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
index 4d8fdcabdb..3ad3d11e2c 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/sync/WorkflowInternal.java
@@ -431,7 +431,7 @@ public static WorkflowInfo getWorkflowInfo() {
 
   public static <T> T getMemo(String key, Class<T> valueClass, Type valueType) {
     Payload memo = getRootWorkflowContext().getContext().getMemo(key);
-    return DataConverter.getDefaultInstance().fromPayload(memo, valueClass, valueType);
+    return getDataConverter().fromPayload(memo, valueClass, valueType);
   }
 
   public static <R> R retry(
diff --git a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
index c594b09f5e..a4dd506609 100644
--- a/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
+++ b/temporal-sdk/src/main/java/io/temporal/workflow/Workflow.java
@@ -24,6 +24,7 @@
 import io.temporal.activity.LocalActivityOptions;
 import io.temporal.api.common.v1.WorkflowExecution;
 import io.temporal.common.RetryOptions;
+import io.temporal.common.converter.DataConverter;
 import io.temporal.failure.ActivityFailure;
 import io.temporal.failure.CanceledFailure;
 import io.temporal.failure.ChildWorkflowFailure;
@@ -615,12 +616,31 @@ public static WorkflowInfo getInfo() {
     return WorkflowInternal.getWorkflowInfo();
   }
 
+  /**
+   * Extract deserialized Memo associated with given key
+   *
+   * @param key memo key
+   * @param valueClass Java class to deserialize into
+   * @return deserialized Memo
+   */
   public static <T> Object getMemo(String key, Class<T> valueClass) {
-    return getMemo(key, valueClass, valueClass.getGenericSuperclass());
+    return getMemo(key, valueClass, valueClass);
   }
 
-  public static <T> T getMemo(String key, Class<T> valueClass, Type valueType) {
-    return WorkflowInternal.getMemo(key, valueClass, valueType);
+  /**
+   * Extract Memo associated with the given key and deserialized into an object of generic type as
+   * is done here: {@link DataConverter#fromPayloads(int, java.util.Optional, java.lang.Class,
+   * java.lang.reflect.Type)} Ex: To deserialize into HashMap<String, Integer> <code>
+   *  Workflow.getMemo(key, Map.class, new TypeToken<HashMap<String, Integer>>() {}.getType());
+   * </code>
+   *
+   * @param key memo key
+   * @param valueClass Java class to deserialize into
+   * @param genericType type parameter for the generic class
+   * @return deserialized Memo
+   */
+  public static <T> T getMemo(String key, Class<T> valueClass, Type genericType) {
+    return WorkflowInternal.getMemo(key, valueClass, genericType);
   }
 
   /**

From 50906b0d0635347a68d0fc8dfff8a6f1867794e3 Mon Sep 17 00:00:00 2001
From: Vera Kobylchak <vera@temporal.io>
Date: Thu, 26 Aug 2021 13:03:29 -0700
Subject: [PATCH 6/6] Minor changes

---
 .../temporal/internal/replay/ReplayWorkflowContext.java  | 5 -----
 .../main/java/io/temporal/internal/worker/Poller.java    | 2 +-
 .../src/test/java/io/temporal/workflow/MemoTest.java     | 2 +-
 .../java/io/temporal/serviceclient/RpcRetryOptions.java  | 9 +++------
 4 files changed, 5 insertions(+), 13 deletions(-)

diff --git a/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java b/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java
index 9f0e96311c..1cf2d15a0a 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/replay/ReplayWorkflowContext.java
@@ -95,11 +95,6 @@ public interface ReplayWorkflowContext extends ReplayAware {
 
   Duration getWorkflowTaskTimeout();
 
-  /**
-   * Used to retrieve the memo.
-   *
-   * @return Memo object
-   */
   Payload getMemo(String key);
 
   /**
diff --git a/temporal-sdk/src/main/java/io/temporal/internal/worker/Poller.java b/temporal-sdk/src/main/java/io/temporal/internal/worker/Poller.java
index 1f4a103cad..ee96a8ae52 100644
--- a/temporal-sdk/src/main/java/io/temporal/internal/worker/Poller.java
+++ b/temporal-sdk/src/main/java/io/temporal/internal/worker/Poller.java
@@ -22,9 +22,9 @@
 import com.uber.m3.tally.Scope;
 import io.grpc.Status;
 import io.grpc.StatusRuntimeException;
+import io.temporal.internal.BackoffThrottler;
 import io.temporal.internal.common.InternalUtils;
 import io.temporal.internal.metrics.MetricsType;
-import io.temporal.internal.BackoffThrottler;
 import java.util.Objects;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.CountDownLatch;
diff --git a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
index c1c58879e6..a5be2570a1 100644
--- a/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
+++ b/temporal-sdk/src/test/java/io/temporal/workflow/MemoTest.java
@@ -22,10 +22,10 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
+import com.google.common.collect.ImmutableMap;
 import com.google.common.reflect.TypeToken;
 import com.google.protobuf.ByteString;
 import com.uber.m3.tally.NoopScope;
-import com.uber.m3.util.ImmutableMap;
 import io.temporal.api.common.v1.Memo;
 import io.temporal.api.common.v1.Payload;
 import io.temporal.api.common.v1.WorkflowExecution;
diff --git a/temporal-serviceclient/src/main/java/io/temporal/serviceclient/RpcRetryOptions.java b/temporal-serviceclient/src/main/java/io/temporal/serviceclient/RpcRetryOptions.java
index 3c307bcc0b..9cea612885 100644
--- a/temporal-serviceclient/src/main/java/io/temporal/serviceclient/RpcRetryOptions.java
+++ b/temporal-serviceclient/src/main/java/io/temporal/serviceclient/RpcRetryOptions.java
@@ -233,16 +233,13 @@ public RpcRetryOptions validateBuildWithDefaults() {
         backoff = DefaultServiceOperationRpcRetryOptions.BACKOFF;
       }
       if (initialInterval == null || initialInterval.isZero() || initialInterval.isNegative()) {
-        initialInterval =
-            DefaultServiceOperationRpcRetryOptions.INITIAL_INTERVAL;
+        initialInterval = DefaultServiceOperationRpcRetryOptions.INITIAL_INTERVAL;
       }
       if (expiration == null || expiration.isZero() || expiration.isNegative()) {
-        expiration =
-            DefaultServiceOperationRpcRetryOptions.EXPIRATION_INTERVAL;
+        expiration = DefaultServiceOperationRpcRetryOptions.EXPIRATION_INTERVAL;
       }
       if (maximumInterval == null || maximumInterval.isZero() || maximumInterval.isNegative()) {
-        maximumInterval =
-            DefaultServiceOperationRpcRetryOptions.MAXIMUM_INTERVAL;
+        maximumInterval = DefaultServiceOperationRpcRetryOptions.MAXIMUM_INTERVAL;
       }
       if (doNotRetry == null || doNotRetry.size() == 0) {
         doNotRetry = DefaultServiceOperationRpcRetryOptions.INSTANCE.doNotRetry;