1z0-829 Free Practice Test

Given:

Which two should the module-info file include for it to represent the service provider interface?

1. A. Requires cm.transport.vehicle,cars:
2. B. Provides.com.transport.vehicle.cars.Car with com.transport.vehicle.car
3. C. impt, CatImpI;
4. D. Requires cm.transport.vehicle,cars:
5. E. Provides.com.transport.vehicle.cars.Car impl,CarImp1 to com.transport.vehicle.car
6. F. Cars
7. G. exports com.transport.vehicle.cars.Car;
8. H. Exports com.transport.vehicle.cars;
9. I. Exports com.transport.vehicle;

Correct Answer: BE
The answer is B and E because the module-info file should include a
provides directive and an exports directive to represent the service provider interface. The provides directive declares that the module provides an implementation of a service interface, which is com.transport.vehicle.cars.Car in this case. The with clause specifies the fully qualified name of the service provider class, which is com.transport.vehicle.cars.impl.CarImpl in this case. The exports directive declares that the module exports a package, which is com.transport.vehicle.cars in this case, to make it available to other modules. The package contains the service interface that other modules can use.
Option A is incorrect because requires is not the correct keyword to declare a service provider interface. Requires declares that the module depends on another module, which is not the case here.
Option C is incorrect because it has a typo in the module name. It should be com.transport.vehicle.cars, not cm.transport.vehicle.cars.
Option D is incorrect because it has a typo in the keyword provides. It should be provides, not Provides. It also has a typo in the service interface name. It should be com.transport.vehicle.cars.Car, not com.transport.vehicle.cars.Car impl. It also has an unnecessary to clause, which is used to limit the accessibility of an exported package to specific modules.
Option F is incorrect because it exports the wrong package. It should export com.transport.vehicle.cars, not com.transport.vehicle.cars.impl. The impl package contains the service provider class, which should not be exposed to other modules.
Option G is incorrect because it exports the wrong package. It should export com.transport.vehicle.cars, not com.transport.vehicle. The vehicle package does not contain the service interface or the service provider class. References:
✑ Oracle Certified Professional: Java SE 17 Developer
✑ Java SE 17 Developer
✑ OCP Oracle Certified Professional Java SE 17 Developer Study Guide
✑ Java Modules - Service Interface Module - GeeksforGeeks
✑ Java Service Provider Interface | Baeldung

Given the code fragments:

Which action prints Wagon : 200?

1. A. At line n1, implement the java.io, Serializable interface.
2. B. At line n3, replace readObject (0 with readLine().
3. C. At Line n3, replace Car with LuxurayCar.
4. D. At Line n1, implement the java.io.AutoCloseable interface
5. E. At line n2, in the main method signature, add throws IOException, ClassCastException.
6. F. At line n2, in the main method signature, add throws IoException, ClassNotFoundException.

Correct Answer: F
The code fragment is trying to read an object from a file using the ObjectInputStream class. This class throws an IOException and a ClassNotFoundException. To handle these exceptions, the main method signature should declare that it throws these exceptions. Otherwise, the code will not compile. If the main method throws these exceptions, the code will print Wagon : 200, which is the result of calling the toString method of the LuxuryCar object that was written to the
file. References: ObjectInputStream (Java SE 17 & JDK 17) - Oracle, ObjectOutputStream (Java SE 17 & JDK 17) - Oracle

Given the code fragment:

What is the result?

1. A. 2
2. B. -2
3. C. 22E.111F.12-4

Correct Answer: B
The code fragment uses the Collections.binarySearch method to search for the string ??e3?? in the list. The first search returns the index of the element, which is 2. The second search returns the index of the element, which is 0. The third search returns the index of the element, which is -4. The final result is 2. References: Collections (Java SE 17 & JDK 17) - Oracle

Assume you have an automatic module from the module path display-ascii-0.2. jar. Which name is given to the automatic module based on the given JAR file?

1. A. Display.ascii
2. B. Display-ascii-0.2
3. C. Display-ascii
4. D. Display-ascii-0

Correct Answer: C
An automatic module name is derived from the name of the JAR file when it does not contain a module-info.class file. If the JAR file has an ??Automatic-Module-Name?? attribute in its main manifest, then its value is the module name. Otherwise, the module name is derived from the JAR file??s name by removing any version numbers and converting it to lower case. Therefore, for a JAR named display-ascii-0.2.jar, the automatic module name would be display-ascii, following these rules.

Given the code fragment:

Which action enables the code to compile?

1. A. Replace record with void.
2. B. Remove the regNO initialization statement.
3. C. Make the regNo variable static.
4. D. Replace thye regNo variable static
5. E. Make the regNo variable public

Correct Answer: E
The code will compile if the regNo variable is made public. This is because the regNo variable is being accessed in the main method of the App class, which is outside the scope of the Product class. Making the regNo variable public will allow it to be accessed from outside the class. References: https://education.oracle.com/products/trackp_OCPJSE17, https://mylearn.oracle.com/ou/learning-path/java-se-17-developer/99487, https://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html