Feat/java/create feature view

[SirOibaf]

This PR adds/fixes/changes...

• please summarize your changes to the code
• and make sure to include all changes to user-facing APIs

JIRA Issue: -

Priority for Review: -

Related PRs: -

How Has This Been Tested?

• Unit Tests
• Integration Tests
• Manual Tests on VM

Checklist For The Assigned Reviewer:

- [ ] Checked if merge conflicts with master exist
- [ ] Checked if stylechecks for Java and Python pass
- [ ] Checked if all docstrings were added and/or updated appropriately
- [ ] Ran spellcheck on docstring
- [ ] Checked if guides & concepts need to be updated
- [ ] Checked if naming conventions for parameters and variables were followed
- [ ] Checked if private methods are properly declared and used
- [ ] Checked if hard-to-understand areas of code are commented
- [ ] Checked if tests are effective
- [ ] Built and deployed changes on dev VM and tested manually
- [x] (Checked if all type annotations were added and/or updated appropriately)

[Copilot]

PR Overview

This PR introduces a new builder pattern for constructing FeatureView objects and extends functionality for feature view and feature group query operations across Beam, Flink, and HSFS modules. Key changes include:

• Adding builder classes and getOrCreate methods for FeatureView in multiple modules.
• Introducing new query methods (e.g., selectFeatures, selectAll, selectExcept) for FeatureGroup objects.
• Extending tagging methods and updating QueryBase from an abstract to a concrete class.

Reviewed Changes

File	Description
java/beam/src/main/java/com/logicalclocks/hsfs/beam/FeatureView.java	Adds FeatureView builder and constructor enhancements.
java/hsfs/src/main/java/com/logicalclocks/hsfs/FeatureView.java	Introduces similar FeatureView builder changes.
java/flink/src/main/java/com/logicalclocks/hsfs/flink/FeatureView.java	Adds builder support for Flink FeatureView.
java/hsfs/src/main/java/com/logicalclocks/hsfs/engine/FeatureViewEngine.java	Implements getOrCreateFeatureView with error handling.
java/flink/src/main/java/com/logicalclocks/hsfs/flink/engine/FeatureViewEngine.java	Mirrors getOrCreateFeatureView functionality for Flink.
java/hsfs/src/main/java/com/logicalclocks/hsfs/engine/FeatureGroupUtils.java	Updates getSubject workaround logic.
java/beam/src/main/java/com/logicalclocks/hsfs/beam/engine/FeatureViewEngine.java	Adds List import and getOrCreateFeatureView for Beam.
java/beam/src/main/java/com/logicalclocks/hsfs/beam/StreamFeatureGroup.java	Adds new query selection methods to Beam FeatureGroup.
java/hsfs/src/main/java/com/logicalclocks/hsfs/FeatureStore.java	Introduces createFeatureView and getOrCreateFeatureView API methods.
java/flink/src/main/java/com/logicalclocks/hsfs/flink/StreamFeatureGroup.java	Adds query methods to Flink FeatureGroup.
java/beam/src/main/java/com/logicalclocks/hsfs/beam/FeatureStore.java	Adds corresponding FeatureStore API changes for Beam.
java/beam/src/main/java/com/logicalclocks/hsfs/beam/constructor/Query.java	Adds Beam-specific Query constructor using FeatureGroupBase.
java/flink/src/main/java/com/logicalclocks/hsfs/flink/FeatureStore.java	Updates FeatureStore API for Flink with builder methods.
java/hsfs/src/main/java/com/logicalclocks/hsfs/StreamFeatureGroup.java	Extends query related methods in HSFS FeatureGroup.
java/hsfs/src/main/java/com/logicalclocks/hsfs/constructor/Query.java	Adds HSFS Query constructor changes.
java/hsfs/src/main/java/com/logicalclocks/hsfs/FeatureViewBase.java	Introduces new tagging and deletion related methods for FeatureView.
java/hsfs/src/main/java/com/logicalclocks/hsfs/FeatureGroupBase.java	Adds new property for feature store identifier.
java/hsfs/src/main/java/com/logicalclocks/hsfs/constructor/QueryBase.java	Changes QueryBase from an abstract to a concrete class.
java/hsfs/src/main/java/com/logicalclocks/hsfs/TrainingDatasetFeature.java	Applies @JsonIgnore annotation to isComplex for serialization control.
java/flink/src/main/java/com/logicalclocks/hsfs/flink/constructor/Query.java	Updates Flink Query constructor accordingly.

Copilot reviewed 24 out of 24 changed files in this pull request and generated 1 comment.

[Copilot]

QueryBase was changed from an abstract class to a concrete class; please verify if this is intentional to avoid accidental instantiation.