1Z0-819 Exam Training Practice Tests (Oracle Java SE 11 Developer)]

Question 1

Given the code fragment:

What is the result?

A. 01 B. The program prints nothing. C. 1 D. 0 E. It prints 1 in the infinite loop.

Correct Answer: B

Question 2

Given:

What is the result?

A. [A, B, C]
followed by an exception thrown on line 11. B. [A, B, C]
[ B, C] C. [A, B, C]
[A, B, C] D. On line 9, an exception is thrown at run time.

Correct Answer: C

Question 3

Your organization makes mlib.jar available to your cloud customers. While working on a code cleanup project for mlib.jar, you see this method by customers:

What security measures should be added to this method so that it meets the requirements for a customer accessible method?

A. Make enableService private. B. Enclose the call to new Socket In an AccessController.doPrivileged block. C. Create a method that validates the hostName and portNumber parameters before opening the socket. D.

Correct Answer: B

Question 4

Which three annotation uses are valid? (Choose three.)

A. Function<String, String> func = (var @NonNull x) -> x.toUpperCase(); B. Function<String, String> func = (@NonNull var x) -> x.toUpperCase(); C. Function<String, String> func = (@NonNull x) -> x.toUpperCase(); D. var v = "Hello" + (@Interned) "World" E. var obj = new @Interned MyObject(); F. var myString = (@NonNull String) str;

Correct Answer: A,C,E

Question 5

Given:

executed using this command:
java Myclass My Car is red
What is the output of this class?

A. Myclass--Car--red B. My--Car--is C. java--Myclass--My D. My--is--java E. Car--red--My

Correct Answer: E

Question 6

Given the code fragment:

Which can replace line 2?

A. UnaryOperator u = (int i) -> i * 2; B. UnaryOperator u = i -> { return i * 2); C. UnaryOperator u = (var i) -> (i * 2); D. UnaryOperator u = var i -> { return i * 2; };

Correct Answer: C

Question 7

Given:

and

What is the result?

A. 1
1
1 B. 1
Null
null C. A NullPointerException is thrown at run time. D. A ClassCastException is thrown at run time. E. The compilation fails.

Correct Answer: E

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Question 8

Given:
jdeps -jdkinternals C:\workspace4\SimpleSecurity\jar\classes.jar
Which describes the expected output?

A. jdeps outputs an error message that the -jdkinternals option requires either the -summary or the - verbose options to output to the console. B. The -jdkinternals option analyzes all classes in the .jar and prints all class-level dependencies. C. The -jdkinternals option analyzes all classes in the .jar for class-level dependencies on JDK internal APIs. If any are found, the results with suggested replacements are output in the console. D. jdeps lists the module dependencies and the package names of all referenced JDK internal APIs. If any are found, the suggested replacements are output in the console.

Correct Answer: C

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Question 9

Given:

You want the code to produce this output:
John
Joe
Jane
Which code fragment should be inserted on line 1 and line 2 to produce the output?

A. Insert Comparator<Person> on line 1.
Insert
public int compare(Person p1, Person p2) {
return p1.name.compare(p2.name);
}
on line 2. B. Insert Comparator<Person> on line 1.
Insert
public int compare(Person person) {
return person.name.compare(this.name);
}
on line 2. C. Insert Comparator<Person> on line 1.
Insert
public int compareTo(Person person) {
return person.name.compareTo(this.name);
}
on line 2. D. Insert Comparable<Person> on line 1.
Insert
public int compare(Person p1, Person p2) {
return p1.name.compare(p2.name);
}
on line 2.

Correct Answer: C

Question 10

Given:
LocalDate d1 = LocalDate.of(1997,2,7);
DateTimeFormatter dtf =
DateTimeFormatter.ofPattern( /*insert code here*/ );
System.out.println(dtf.format (d1));
Which pattern formats the date as Friday 7th of February 1997?

A. "eeee d'th of' MMMM yyyy" B. "eeee dd+"th of"+ MMM yyyy" C. "eeee dd'th of' MMM yyyy" D. "eeee d+"th of"+ MMMM yyyy"

Correct Answer: A

Question 11

Given:

Which two lines inserted in line 1 will allow this code to compile? (Choose two.)

A. public abstract void walk(); B. protected void walk(){} C. void walk(){} D. private void walk(){} E. abstract void walk();

Correct Answer: A,B

Question 12

Given the code fragment:

What is the output?

A. Null B. Def 42 C. An exception is thrown at runtime D. 41 def 42

Correct Answer: A

Question 13

Given:

What is the result?

A. The compilation fails at line 2. B. The compilation fails at line 8. C. Hello World D. The compilation fails at line 9.

Correct Answer: C

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Oracle Java SE 11 Developer - 1Z0-819 Exam Practice Test