Support AutoGeneratedTimestamp and UpdateBehavior annotation in nested objects

[anasatirbasa]

Description

Added support for @DynamoDbAutoGeneratedTimestampAttribute and @DynamoDbUpdateBehavior on attributes within nested objects. The @DynamoDbUpdateBehavior annotation will only take effect for nested attributes when using IgnoreNullsMode.SCALAR_ONLY.

Motivation and Context

@DynamoDbUpdateBehavior and @DynamoDbAutoGeneratedTimestampAttribute to work on nested objects too.

Modifications

The AutoGeneratedTimestampRecordExtension has been enhanced to support detection of the timestamp annotation on nested objects. Depending on the operation and the IgnoreNullsMode setting, nested attributes may either be treated as complete maps or flattened using the NESTED_ATTR_UPDATE convention (handled in transformItemToMapForUpdateExpression within UpdateItemOperation). Both scenarios are now supported, and the same generated timestamp is applied consistently across top-level and nested fields.

In parallel, the handling of the IgnoreNullsMode parameter within update requests was reviewed. As a result, UpdateExpressionUtils has been updated to evaluate the @DynamoDbUpdateBehavior annotation only when IgnoreNullsMode.SCALAR_ONLY is used, targeting flattened nested attributes identified via NESTED_ATTR_UPDATE. When applied to a list of nested objects, the annotation is not supported, as individual elements cannot be updated — the entire list is replaced during an update operation

Testing

Existing tests were updated, and new tests were added to validate the extended functionality.

Test Coverage Checklist

Scenario	Done	Comments if Not Done
1. Different TableSchema Creation Methods
a. TableSchema.fromBean(Customer.class)	[x]
b. TableSchema.fromImmutableClass(Customer.class) for immutable classes	[x]
c. TableSchema.documentSchemaBuilder().build()	[x]
d. StaticTableSchema.builder(Customer.class)	[x]
**2. Nesting of Different TableSchema Types ** (Ref-1)
a. @DynamoDbBean with non-null nested @DynamoDbBean attribute	[x]
b. @DynamoDbBean with non-null nested @DynamoDbImmutable attribute	[ ]
c. @DynamoDbImmutable with non-null nested @DynamoDbBean attribute	[ ]
d. @DynamoDbBean with null nested @DynamoDbBean attribute	[x]
e. @DynamoDbBean with null nested @DynamoDbImmutable attribute	[ ]
f. @DynamoDbImmutable with null nested @DynamoDbBean attribute	[ ]
3. CRUD Operations (Ref-2)		Existing tests passed
a. scan()	[ ]
b. query()	[ ]
c. updateItem()	[x]
d. putItem()	[x]
e. getItem()	[x]
f. deleteItem()	[ ]
g. batchGetItem()	[ ]
h. batchWriteItem()	[ ]
i. transactGetItems()	[ ]
j. transactWriteItems()	[ ]
4. Null Handling for Different Attribute types (Ref-3)
a. top-level null attributes	[x]
b. collections with null elements	[ ]
c. maps with null values	[ ]
d. full serialization/deserialization cycle with null values	[ ]
5. AsyncTable and SyncTable		Existing tests passed
a. DynamoDbAsyncTable Testing	[ ]
b. DynamoDbTable Testing	[x]
6. New/Modification in Extensions
a. Tables with Scenario in ScenarioSl No.1 (All table schemas are Must)	[x]
b. Test with Default Values in Annotations	[x]
c. Combination of Annotation and Builder passes extension	[x]
7. New/Modification in Converters		Not impacted, existing tests passed
a. Tables with Scenario in ScenarioSl No.1 (All table schemas are Must)	[ ]
b. Test with Default Values in Annotations	[ ]
c. Test All Scenarios from 1 to 5	[ ]

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist

• I have read the CONTRIBUTING document
• Local run of mvn install succeeds
• My code follows the code style of this project
• My change requires a change to the Javadoc documentation
• I have updated the Javadoc documentation accordingly
• I have added tests to cover my changes
• All new and existing tests passed
• I have added a changelog entry. Adding a new entry must be accomplished by running the scripts/new-change script and following the instructions. Commit the new file created by the script in .changes/next-release with your changes.
• My change is to implement 1.11 parity feature and I have updated LaunchChangelog

License

• I confirm that this pull request can be released under the Apache 2 license