Get retiring federator public key optional

[julianlen]

Description

Motivation and Context

How Has This Been Tested?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• Tests for the changes have been added (for bug fixes / features)
• Requires Activation Code (Hard Fork)

• Other information:

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[Copilot]

Pull request overview

This PR refactors the getRetiringFederatorBtcPublicKey method to return an Optional<BtcECKey> instead of a nullable byte[]. This change improves type safety by making the absence of a retiring federator public key explicit through the Optional type, eliminating null checks and promoting better API design.

Key Changes:

• Modified method signature to return Optional<BtcECKey> instead of byte[]
• Updated implementations to return Optional.empty() instead of null when no retiring federation exists
• Refactored empty byte array returns to use EMPTY_BYTE_ARRAY constant throughout the Bridge class

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
FederationSupport.java	Updated interface method signature and documentation to return Optional
FederationSupportImpl.java	Modified implementation to return Optional and handle empty case with Optional.empty()
BridgeSupport.java	Updated method signature to match new return type
Bridge.java	Refactored to use Optional API and replaced inline empty byte arrays with EMPTY_BYTE_ARRAY constant
FederationSupportImplTest.java	Updated test assertions to check for empty Optional instead of null values
BridgeSupportTest.java	Modified mock setup and assertions to work with Optional return type
BridgeSupportIT.java	Updated integration tests to assert on Optional presence and extract values properly
BridgeIT.java	Refactored test to use parameterized testing and updated mock to return Optional

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[Copilot]

The method getRetiringFederatorBtcPublicKey(0) is called twice consecutively on lines 521 and 522. Store the result in a variable to avoid redundant method calls.

Suggested change

	assertTrue(bridgeSupport.getRetiringFederatorBtcPublicKey(0).isPresent());
	assertEquals(bridgeSupport.getRetiringFederatorBtcPublicKey(0).get(), publicKey);
	Optional<BtcECKey> actualPublicKeyOptional = bridgeSupport.getRetiringFederatorBtcPublicKey(0);
	assertTrue(actualPublicKeyOptional.isPresent());
	assertEquals(actualPublicKeyOptional.get(), publicKey);

[julianlen]

done

[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

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[Copilot]

The variable name publicKey is ambiguous since it stores an Optional<BtcECKey> (the full key object), not the raw public key bytes. Consider renaming to retiringFederatorKey or retiringFederatorBtcKey to better reflect what it contains.

Suggested change

	Optional<BtcECKey> publicKey = bridgeSupport.getRetiringFederatorBtcPublicKey(index);
	return publicKey.map(BtcECKey::getPubKey).orElse(EMPTY_BYTE_ARRAY);
	Optional<BtcECKey> retiringFederatorBtcKey = bridgeSupport.getRetiringFederatorBtcPublicKey(index);
	return retiringFederatorBtcKey.map(BtcECKey::getPubKey).orElse(EMPTY_BYTE_ARRAY);

[julianlen]

done

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud