add class Machine and classes Truck, Bulldozer, and Excavator

[KhapalSofiia]

Also added methods doWork() and stopWork().

[mateacademy-ai-mentor]

Review Summary

Decision: APPROVE

Why: All core requirements are fully met: Machine is abstract with doWork()/stopWork(), subclasses override correctly with clear English messages, and MainApp uses a Machine[] and loops calling both methods. Functionality is correct and nothing blocks execution.

Minor improvements (non-blockers):

• Remove redundant empty lines immediately after the package declaration in these files: Machine.java, MainApp.java, Truck.java, Bulldozer.java, Excavator.java (violates the “no redundant empty lines” checklist). For example, in each file, delete the blank line right after package core.basesyntax;.
• Remove redundant semicolons after method bodies in Truck.java, Bulldozer.java, and Excavator.java (e.g., after the closing brace of doWork()), as they’re unnecessary.

Great job on abstraction and polymorphism. Tidy up the minor style issues when you can to align perfectly with the checklist.

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Footnotes

1. Rate AI review example ↩

[mateacademy-ai-mentor]

There is a redundant empty line after the package declaration. This violates checklist item: "Please don't add redundant empty lines to your code."

[mateacademy-ai-mentor]

There is a redundant semicolon after the closing brace of the doWork() method. While this does not break functionality, it is unnecessary and should be removed for cleaner code.

[mateacademy-ai-mentor]

There is a redundant empty line after the package declaration. This violates checklist item: "Please don't add redundant empty lines to your code."

[mateacademy-ai-mentor]

There is a redundant semicolon after the closing brace of the doWork() method. While this does not break functionality, it is unnecessary and should be removed for cleaner code.

[mateacademy-ai-mentor]

There is a redundant empty line after the package declaration. This violates checklist item: "Please don't add redundant empty lines to your code."

[mateacademy-ai-mentor]

There is a redundant empty line after the package declaration. This violates checklist item: "Please don't add redundant empty lines to your code."

[mateacademy-ai-mentor]

There is a redundant empty line after the package declaration. This violates checklist item: "Please don't add redundant empty lines to your code."

[mateacademy-ai-mentor]

There is a redundant semicolon after the closing brace of the doWork() method. While this does not break functionality, it is unnecessary and should be removed for cleaner code.