Enhanced DynamoDB NPE on putItem with null map value #2282

public class SDKTest {

  public static final StaticTableSchema<Chapter> CHAPTER_SCHEMA = StaticTableSchema.builder(Chapter.class)
    .newItemSupplier(Chapter::new)
    .addAttribute(Integer.class, a -> a.name("page").getter(Chapter::getPage).setter(Chapter::setPage))
    .addAttribute(String.class, a -> a.name("text").getter(Chapter::getText).setter(Chapter::setText))
    .build();

  public static final StaticTableSchema<Book> BOOK_SCHEMA = StaticTableSchema.builder(Book.class)
    .newItemSupplier(Book::new)
    .addAttribute(String.class, a -> a.name("id").tags(primaryPartitionKey()).getter(Book::getId).setter(Book::setId))
    .addAttribute(EnhancedType.mapOf(EnhancedType.of(String.class), EnhancedType.documentOf(Chapter.class, CHAPTER_SCHEMA)),
      a -> a.name("map").getter(Book::getChapters).setter(Book::setChapters))
    .build();

  @DynamoDbBean
  public static class Book {
    private String id;
    private Map<String, Chapter> chapters;

    public Book() {}
    public Book(String id) { setId(id); }

    @DynamoDbPartitionKey public String getId() {  return id; }
    public void setId(String id) {  this.id = id; }

    public Map<String, Chapter> getChapters() { return chapters; }
    public void setChapters(Map<String, Chapter> chapters) {  this.chapters = chapters;  }
  }

  @DynamoDbBean
  public static class Chapter {
    private Integer page;
    private String text;

    public Integer getPage() {  return page;  }
    public void setPage(Integer page) {  this.page = page;  }

    public String getText() {  return text;  }
    public void setText(String text) {  this.text = text;  }
  }

  public void testStatic(DynamoDbClient client, DynamoDbEnhancedClient enhancedClient) throws Exception {
    DynamoDbTable<Book> table = enhancedClient.table("books", BOOK_SCHEMA);
    table.createTable();

    client.putItem(b -> b.tableName("books")
      .item(new HashMap<String, AttributeValue>() {{
        put("id", AttributeValue.builder().s("123").build());
        put("chapters", AttributeValue.builder()
          .m(Collections.singletonMap("First", AttributeValue.builder().nul(true).build()))
          .build());
      }}));

    Book item = table.getItem(new Book("123"));
    table.putItem(item);
  }

  public void testBean(DynamoDbClient client, DynamoDbEnhancedClient enhancedClient) throws Exception {
    DynamoDbTable<Book> table = enhancedClient.table("books", TableSchema.fromBean(Book.class));
    table.createTable();

    client.putItem(b -> b.tableName("books")
      .item(new HashMap<String, AttributeValue>() {{
        put("id", AttributeValue.builder().s("123").build());
        put("chapters", AttributeValue.builder()
          .m(Collections.singletonMap("First", AttributeValue.builder().nul(true).build()))
          .build());
      }}));

    Book item = table.getItem(new Book("123"));
    table.putItem(item); // <------------------------------LINE THAT THROWS EXCEPTION
  }
}

java.lang.NullPointerException
	at software.amazon.awssdk.enhanced.dynamodb.internal.mapper.ResolvedImmutableAttribute.lambda$create$0(ResolvedImmutableAttribute.java:48)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema.lambda$itemToMap$5(StaticImmutableTableSchema.java:491)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema.itemToMap(StaticImmutableTableSchema.java:489)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.WrappedTableSchema.itemToMap(WrappedTableSchema.java:59)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.WrappedTableSchema.itemToMap(WrappedTableSchema.java:59)
	at software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute.DocumentAttributeConverter.transformFrom(DocumentAttributeConverter.java:47)
	at software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute.MapAttributeConverter$Delegate.lambda$toAttributeValue$0(MapAttributeConverter.java:165)
	at software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute.MapAttributeConverter$Delegate.toAttributeValue(MapAttributeConverter.java:165)
	at software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute.MapAttributeConverter.transformFrom(MapAttributeConverter.java:138)
	at software.amazon.awssdk.enhanced.dynamodb.internal.converter.attribute.MapAttributeConverter.transformFrom(MapAttributeConverter.java:76)
	at software.amazon.awssdk.enhanced.dynamodb.internal.mapper.StaticAttributeType.objectToAttributeValue(StaticAttributeType.java:40)
	at software.amazon.awssdk.enhanced.dynamodb.internal.mapper.ResolvedImmutableAttribute.lambda$create$0(ResolvedImmutableAttribute.java:49)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema.lambda$itemToMap$5(StaticImmutableTableSchema.java:491)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.StaticImmutableTableSchema.itemToMap(StaticImmutableTableSchema.java:489)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.WrappedTableSchema.itemToMap(WrappedTableSchema.java:59)
	at software.amazon.awssdk.enhanced.dynamodb.mapper.WrappedTableSchema.itemToMap(WrappedTableSchema.java:59)
	at software.amazon.awssdk.enhanced.dynamodb.internal.operations.PutItemOperation.generateRequest(PutItemOperation.java:71)
	at software.amazon.awssdk.enhanced.dynamodb.internal.operations.PutItemOperation.generateRequest(PutItemOperation.java:40)
	at software.amazon.awssdk.enhanced.dynamodb.internal.operations.CommonOperation.execute(CommonOperation.java:113)
	at software.amazon.awssdk.enhanced.dynamodb.internal.operations.TableOperation.executeOnPrimaryIndex(TableOperation.java:59)
	at software.amazon.awssdk.enhanced.dynamodb.internal.client.DefaultDynamoDbTable.putItem(DefaultDynamoDbTable.java:179)
	at software.amazon.awssdk.enhanced.dynamodb.internal.client.DefaultDynamoDbTable.putItem(DefaultDynamoDbTable.java:187)
	at software.amazon.awssdk.enhanced.dynamodb.internal.client.DefaultDynamoDbTable.putItem(DefaultDynamoDbTable.java:192)
	at com.magicbinder.core.SDKTest.testBean