[FLINK-35148] Improve InstantiationUtil for checking nullary public constructor

• Type: Technical Debt
• Status: Closed
• Priority: Minor
• Resolution: Done
• Fix Version/s: 1.20.0
• Component/s: API / Core
• Labels: pull-request-available
• Assignee: Mingliang Liu
• Reporter: Mingliang Liu
• Created: 17/Apr/24 22:28
• Updated: 24/Apr/24 10:10
• Resolved: 24/Apr/24 10:10

Description

InstantiationUtil#hasPublicNullaryConstructor checks whether the given class has a public nullary constructor. The implementation can be improved a bit: the `Modifier#isPublic` check within the for-loop can be skipped as the Class#getConstructors() only returns public constructors.

We can also add a negative unit test for this.

Issue Links

• links to: GitHub Pull Request #24675