Java Platform Overview and Packaging →mediumMultiple ChoiceObjective-mapped

1Z0-829 Java Platform Overview and Packaging Practice Question

Given two named modules where module com.example.app requires module com.example.lib, which packages of com.example.lib are readable by com.example.app?

⚠ Common exam trap

Many candidates confuse `opens` with `exports`, thinking that opening a package for reflection also makes it readable, but `opens` only grants reflective access and does not allow compile-time or direct read access.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Only the packages exported by com.example.lib

In the Java module system, a module can only access packages from another module that are explicitly exported using the `exports` directive in the module's `module-info.java` file. Since `com.example.app` requires `com.example.lib`, only the packages exported by `com.example.lib` are readable; unexported packages remain encapsulated and inaccessible.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
All packages except those explicitly concealed
Why it's wrong here
All non-exported packages are concealed regardless of explicit concealment.
✗
All packages of com.example.lib
Why it's wrong here
Non-exported packages are not readable.
✗
Only the packages opened by com.example.lib
Why it's wrong here
Open packages are for reflective access, not readability.
✓
Only the packages exported by com.example.lib
Why this is correct
A module reads only exported packages of required modules.

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1Z0-829 Java Platform Overview and Packaging Practice Question

Why each option matters

Option-by-option breakdown

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