Download Oracle 1Z0-819 Mock Test Study Material [Q138-Q156]

Download Oracle 1Z0-819 Mock Test Study Material

1Z0-819 Questions Prepare with Learning Information

The Oracle 1Z0-819 exam is aimed at developers who have at least 6 months of experience in Java programming and are familiar with the basics of Java SE 11. It consists of 60 multiple-choice questions and has a time limit of 150 minutes. 1Z0-819 exam is available in several languages, including English, Japanese, Chinese, and Korean. Passing the Oracle 1z1-819 exam is a great way to enhance your career opportunities as a Java developer and improve your credibility in the industry.

NEW QUESTION # 138
Given:

And the commands:
What is the result on execution of these commands?

Answer: D

NEW QUESTION # 139
Which two safely validate inputs? (Choose two.)

A. Delegate numeric range checking of values to the database.
B. Accept only valid characters and input values.
C. Use trusted domain-specific libraries to validate inputs.
D. Modify the input values, as needed, to pass validation.
E. Assume inputs have already been validated.

Answer: A,B

NEW QUESTION # 140
Which two are functional interfaces? (Choose two.)

A. Option D
B. Option C
C. Option B
D. Option A
E. Option E

Answer: B,E

NEW QUESTION # 141
Given the code fragment:

What is the result?

A. 2 : -1
B. 3 : 0
C. 2 : 3
D. -1 : 2

Answer: A

NEW QUESTION # 142
Given:

What is true?

A. This may not print the same result each time the program runs.
B. A NoSuchElementExceptionis thrown at run time.
C. This should print the same result each time the program runs.
D. The compilation fails.

Answer: A

Explanation:

NEW QUESTION # 143
Which set of commands is necessary to create and run a custom runtime image from Java source files?

A. javac, jlink
B. java, jdeps
C. jar, jlink
D. javac, jar

Answer: A

NEW QUESTION # 144
Given:

Which is true?

A. The compilation fails due to an error in line 4.
B. The compilation fails due to an error in line 10.
C. The compilation fails due to an error in line 2.
D. The compilation fails due to an error in line 6.
E. The compilation succeeds.
F. The compilation fails due to an error in line 9.
G. The compilation fails due to an error in line 7.

Answer: D

NEW QUESTION # 145
Given TripleThis.java:

Compiling TripleThis.java gives this compiler warning:
Note: TripleThis.java uses unchecked or unsafe operations.
Which two replacements done together remove this compiler warning?

A. Replace line 9 with function<Integer> tripler = x-> - { return (Integer) X * 3 ; }.
B. Replace line 9 with function<Integer>, Integer> = X -> { return (integer) x * 3; }.
C. Replace line 12 with public static void printValue function<Integer> f, int num) {.
D. Replace line 12 with public static <T> void printValue (Function<T, T> f, T num ) {,
E. Replace line 12 with public static int printValue function<Integer, Integer>, f, T num {.

Answer: A,E

NEW QUESTION # 146
Which three initialization statements are correct? (Choose three.)

A. String contact# = "(+2) (999) (232)";
B. short sh = (short)'A';
C. byte b = 10;char c = b;
D. boolean true = (4 == 4);
E. float x = 1.99;
F. int x = 12_34;
G. int[][] e = {{1,1},{2,2}};

Answer: B,F,G

NEW QUESTION # 147
Given:

What is the output?

A. 1 2 [1, 2, 3, four] 3 four
B. 1 2 [1, 2, 3, 4] 3 four
C. 1 2 [1, 2, 3, 4] 3 4
D. 1 2 [1, 2, 3, four] 3 4

Answer: C

NEW QUESTION # 148
Given:

Which statement is equivalent to line 1?

A. double totalSalary = list.stream().map(Employee::getSalary * ratio).reduce (bo).orElse(0.0);
B. double totalSalary = list.stream().map(e > e.getSalary() * ratio).reduce (bo).ifPresent (p > p.doubleValue());
C. double totalSalary = list.stream().mapToDouble(e > e.getSalary() * ratio).reduce(starts, bo);
D. double totalSalary = list.stream().mapToDouble(e > e.getSalary() * ratio).sum;

Answer: A

Explanation:

NEW QUESTION # 149
Given:

This code results in a compilation error.
Which code should be inserted on line 1 for a successful compilation?

A. Consumer consumer = msg -> { return System.out.print(msg); };
B. Consumer consumer = var arg > {System.out.print(arg);};
C. Consumer consumer = (String args) > System.out.print(args);
D. Consumer consumer = System.out::print;

Answer: D

Explanation:

NEW QUESTION # 150
Given:

Which is true?

A. System.in is the standard input stream. The stream is already open.
B. System.out is an instance of java.io.OutputStream by default.
C. System.out is the standard output stream. The stream is open only when System.out is called.
D. System.in cannot reassign the other stream.

Answer: A

NEW QUESTION # 151
Given:

What is known about the Sportscar class?

A. The Sportscar subclass cannot override setTurbo method from the superclass Automobile.
B. The Sportscar class inherits the setTurbo method from the superclass Automobile.
C. The Sportscar class is a subclass of Automobile and inherits its methods.
D. The Sportscar class is a superclass that has more functionality than the Automobile class.

Answer: C

NEW QUESTION # 152
Given:

Examine these requirements:
* Eliminate code duplication.
* Keep constant the number of methods other classes may implement from this interface.
Which method can be added to meet these requirements?

A. Option D
B. Option B
C. Option A
D. Option C

Answer: B

NEW QUESTION # 153
Given:

What is the result?

A. Good Morning, Harry
B. Good Night, Harry
C. Good Night, Potter
D. Good Morning, Potter

Answer: C

Explanation:

NEW QUESTION # 154
A company has an existing sales application using a Java 8 jar file containing packages:
com.company.customer;
com.company.customer.orders;
com.company.customer.info;
com.company.sales;
com.company.sales.leads;
com.company.sales.closed;
com.company.orders;
com.company.orders.pending;
com.company.orders.shipped.
To modularize this jar file into three modules, customer, sales, and orders, which module-info.java would be correct?