OCP Java Platform Module System 2

Question 1

Which directive in module-info.java allows a module to expose a package for deep reflection at runtime without exporting it for compile-time access?

Accepted Answer

opens

Answer

The `opens` directive allows reflective access to a package at runtime but does not export it for use at compile time.

Question 2

What happens when a module declares `requires transitive com.utils;` and another module depends on that module?

Accepted Answer

Downstream modules automatically read com.utils without declaring requires

Answer

`requires transitive` implies readability, so any module that reads the declaring module also automatically reads com.utils.

Question 3

Which tool is used to create a custom runtime image that contains only the modules needed by an application?

Accepted Answer

jlink

Answer

`jlink` assembles a set of modules and their dependencies into a custom, minimal JVM runtime image.

Question 4

A module named `com.app` contains package `com.app.internal`. Which declaration restricts its export to only `com.trusted` module?

Accepted Answer

exports com.app.internal to com.trusted;

Answer

The `exports ... to` qualified export restricts which specific modules can access the exported package.

Question 5

Which command-line option allows code in an unnamed module to access a package from a named module that does not export it?

Accepted Answer

--add-exports

Answer

`--add-exports` overrides module boundaries at runtime or compile time to expose a package that is not otherwise exported.

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