說明
Do not use wildcard (star) imports. Every import must name the specific class being used.
為什麼重要
- Readability — the reader knows exactly which types are used
- Namespace safety — avoids accidental name collisions
- Refactoring safety — IDE refactors can track individual imports
Enforcement
<module name="AvoidStarImport"/>
SF_SWITCH_NO_DEFAULT — star imports can mask missing imports in switch statements.
正例
import java.util.List;
import java.util.Map;
import java.util.HashMap;
反例
import java.util.*; // ❌ wildcard import