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What you'll learn

• import module M; imports every package exported by module M in one declaration
• unless M is java.base, the declaration also pulls in every package exported by java.base itself
• that extra rule can make a bare type name ambiguous (java.util.List vs java.awt.List when importing java.desktop)
• a regular single-type import still wins over a module import and resolves the ambiguity

Why it matters

Module imports are a convenient shortcut for exploration and scripting, but mixing them with GUI-ish modules like java.desktop can silently shadow common java.util/java.io types - knowing the resolution order avoids confusing compile errors.

Read more

JEP 511: Module Import Declarations

Quiz

Given import module java.desktop; and no other import, does List<String> names = List.of("a"); compile?

Answer

No - it fails with "reference to List is ambiguous" because `java.desktop` exports `java.awt.List` and, since it isn't `java.base`, the declaration also imports `java.base`'s packages, which include `java.util.List`. Adding `import java.util.List;` resolves it, since a single-type import takes precedence over a module import.

Closes #90

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Test Results

278 tests  +2   275 ✅ +2   5s ⏱️ -1s
 80 suites ±0     3 💤 ±0 
 80 files   ±0     0 ❌ ±0 

Results for commit 29484f4. ± Comparison against base commit ae4119f.

This pull request skips 1 and un-skips 1 tests.

pl.mperor.lab.java.design.pattern.creational.singleton.SingletonTest ‑ testLazyInitialized()

pl.mperor.lab.java.design.pattern.creational.singleton.SingletonTest ‑ testSerializationSafe()

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