Oracle 1Z0-816 問題集

質問 1：
Given:

And the command:
java Main Helloworld
What is the result ?
A. Input: Echo:
B. Input:
Then block until any input comes from System.in.
C. A NullPointerException is thrown at run time.
D. Input:
Echo: Helloworld
E. Input: Helloworld Echo: Helloworld
正解：B
解説: (Topexam メンバーにのみ表示されます)

質問 2：
Given the code fragment:
Path currentFile = Paths.get("/scratch/exam/temp.txt");
Path outputFile = Paths get("/scratch/exam/new.txt");
Path directory = Paths.get("/scratch/");
Files.copy(currentFile, outputFile);
Files.copy(outputFile, directory);
Files.delete (outputFile);
The /scratch/exam/temp.txt file exists. The /scratch/exam/new.txt and /scratch/new.txt files do not exist.
What is the result?
A. The program throws a FileaAlreadyExistsException.
B. The program throws a NoSuchFileException.
C. A copy of /scratch/exam/new.txt exists in the /scratch directory and /scratch/exam/new.txt is deleted.
D. /scratch/exam/new.txt and /scratch/new.txt are deleted.
正解：B
解説: (Topexam メンバーにのみ表示されます)

質問 3：
Given:

What is the output?
A. :APPLE:ORANGE:BANANA
appleorangebanana
B. apple:APPLE orange:ORANGE banana:BANANA
C. APPLE:apple ORANGE:orange BANANA:banana
D. :APPLE:ORANGE:BANANA
E. appleorangebanana
:APPLE:ORANGE:BANANA
正解：B
解説: (Topexam メンバーにのみ表示されます)

質問 4：
Given the code fragment:
var pool = Executors.newFixedThreadPool(5);
Future outcome = pool.submit(() -> 1);
Which type of lambda expression is passed into submit()?
A. java.lang.Runnable
B. java.util.function.Predicate
C. java.util.concurrent.Callable
D. java.util.function.Function
正解：C
解説: (Topexam メンバーにのみ表示されます)

質問 5：
Given:

Which two are secure serialization of these objects? (Choose two.)
A. Implement only readResolve to replace the instance with a serial proxy and not writeReplace.
B. Declare fields transient.
C. Define the serialPersistentFields array field.
D. Make the class abstract.
E. Implement only writeReplace to replace the instance with a serial proxy and not readResolve.
正解：A,C

質問 6：
Examine these module declarations:

Which two statements are correct? (Choose two.)
A. The Consumer module should require the ServiceProvider module.
B. The placement of the com.example.api API in a separate module, ServiceAPI, makes it easy to install multiple provider modules.
C. The ServiceProvider module does not know the identity of a module (such as Consumer) that uses the com.example.api API.
D. The ServiceProvider module should export the com.myimpl package.
E. The ServiceProvider module is the only module that, at run time, can provide the com.example.api API.
正解：A,E

質問 7：
Which two statements correctly describe capabilities of interfaces and abstract classes? (Choose two.)
A. Both interfaces and abstract classes can have final methods.
B. Interfaces cannot have protected methods but abstract classes can.
C. Interfaces cannot have methods with bodies but abstract classes can.
D. Interfaces cannot have instance fields but abstract classes can.
E. Interfaces cannot have static methods but abstract classes can.
正解：B,D
解説: (Topexam メンバーにのみ表示されます)

質問 8：
Given:

What code must you insert on Line 1 to enable the code to print Hello world?
A. Hello myH = new Hello();
Hello.Greeting myG = myH.new Greeting();
myG.sayHi();
B. Hello.Greeting myG = new Hello.Greeting() myG.sayHi();
C. Hello myH = new Hello(); Greeting myG = new Greeting(); myG.sayHi ();
D. Hello myH = new Hello();
Hello.Greeting myG = myH.new Hello.Greeting();
myG.sayHi();
正解：A