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Given the code fragment:

What is the result?

invalid
An exception is thrown at runtime.
NULL
Compilation fails.
blank

Correct answer: B

Explanation:

A java.lang.NullPointerException is through at line switch(str) {.

Given:

Which result is possible?

Compilation fails.
L1 L2 L3
L2 L3
L1 L3
L3

Correct answer: B

Explanation:

The Runnable interface should be implemented by any class whose instances are intended to be executed by a thread. The class must define a method of no arguments called run. This interface is designed to provide a common protocol for objects that wish to execute code while they are active. Reference: http://docs.oracle.com/javase/7/docs/api/java/lang/Runnable.html

The Runnable interface should be implemented by any class whose instances are intended to be executed by a thread. The class must define a method of no arguments called run.

This interface is designed to provide a common protocol for objects that wish to execute code while they are active.

Reference: http://docs.oracle.com/javase/7/docs/api/java/lang/Runnable.html

Given the code fragment:

What is the result?

[x, x]
[x, x, x, x]
[x, x]
[x]
[x, x]
[x, x, x]
[x]
[x, x]
[x, x, x]
[x, x, x, x]

Correct answer: D

Explanation:

CyclicBarrier is a synchronization aid that allows a set of threads to all wait for each other to reach a common barrier point. CyclicBarriers are useful in programs involving a fixed sized party of threads that must occasionally wait for each other. The barrier is called cyclic because it can be re-used after the waiting threads are released. Reference: https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/CyclicBarrier.html

CyclicBarrier is a synchronization aid that allows a set of threads to all wait for each other to reach a common barrier point. CyclicBarriers are useful in programs involving a fixed sized party of threads that must occasionally wait for each other. The barrier is called cyclic because it can be re-used after the waiting threads are released.

Reference: https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/CyclicBarrier.html

In 2015. daylight saving time in New York, USA, begins on March 8th at 2:00 AM. As a result, 2:00 AM becomes 3:00 AM.

Given the code fragment:

Which is the result?

2:00 – difference: 1
3:00 – difference: 2
4:00 – difference: 3
4:00 – difference: 2

Correct answer: D

Explanation:

Reference: http://docs.oracle.com/javase/8/docs/api/java/time/ZoneId.html

Given the code fragment:

What is the result?

A compilation error occurs.
An IllegalStateException is thrown at run time.
Tom, Hello
Joe, Hello
Tom,
Joe,

Correct answer: C

Explanation:

Output:Tom,Hello Joe,Hello

Output:

Tom,Hello

Joe,Hello

Given the code fragment:

If exceptions occur when closing the FileWriter object and when retrieving the JString class object, which exception object is propagated up to the caller of

the processFile method?

java.lang.Exception
java.io.IOException
java.lang.ClassNotFoundException
java.lang.NoSuchClassException

Correct answer: C

Explanation:

ClassNotFoundException is thrown when an application tries to load in a class through its string name using:The forName method in class Class. The findSystemClass method in class ClassLoader . The loadClass method in class ClassLoader. but no definition for the class with the specified name could be found. References: https://docs.oracle.com/javase/7/docs/api/java/lang/ClassNotFoundException.html

ClassNotFoundException is thrown when an application tries to load in a class through its string name using:

The forName method in class Class.
The findSystemClass method in class ClassLoader .
The loadClass method in class ClassLoader.

but no definition for the class with the specified name could be found.

References: https://docs.oracle.com/javase/7/docs/api/java/lang/ClassNotFoundException.html

Given:

What is the result when you compile the code and execute the command:

java MyApp kava

kava
Kava
kawa
Kawa
An exception is thrown at runtime.

Correct answer: D

Given the code fragment:

and

Which code fragment could you see to refactor the code from line 4 to 8 to use a Lambda expression?

Vehicle v = new Vehicle(int speed) { System.out.print(“Fly at “ + speed); );
Vehicle v = int speed -> System.out.print(“Fly at “ + speed);
Vehicle v = (int speed) -> System.out.print(“Fly at “ + speed);
Vehicle v = speed -> {System.out.print(“Fly at “ + speed) };

Correct answer: C

Given the code fragment:

What is the result?

0 0
1 2
1 4
A compilation error occurs

Correct answer: D

Explanation:

A compilation error will occur at the following line:map.compute("1", (k, v) -> (v == null) ? k * k : 0 );The error is:Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - bad operand types for binary operator '*'first type: java.lang.Stringsecond type: java.lang.String

A compilation error will occur at the following line:

map.compute("1", (k, v) -> (v == null) ? k * k : 0 );

The error is:

Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - bad operand types for binary operator '*'

first type: java.lang.String

second type: java.lang.String

Given the incomplete pseudo-code for a fork/join framework application:

And given the missing methods:

process, submit, and splitInHalf

Which three insertions properly complete the pseudo-code? (Choose three.)

Insert process at line Z.
Insert process at line X.
Insert submit at line X.
Insert splitInHalf at line X.
Insert process at line Y.
Insert splitInHalf at line Y.
Insert submit at line Z.

Correct answer: BFG

Explanation:

B: If the size is small enough then process the work.D: If the size is not small enough then slit up the wok in half.G: Submit the two split up pieces of work recursively.Note: Your code should look similar to the following pseudocode: Reference: https://docs.oracle.com/javase/tutorial/essential/concurrency/forkjoin.html

B: If the size is small enough then process the work.

D: If the size is not small enough then slit up the wok in half.

G: Submit the two split up pieces of work recursively.

Note: Your code should look similar to the following pseudocode: