Free 1Z0-815 Exam Dumps Preview

Question 1

Single choice

Given:

executed with this command:

java Main one two three

What is the result?

1. A

   0). one

2. B

   0). one

   1). two
   2). three

3. C

   The compilation fails.

4. D

   It creates an infinite loop printing:
   0). one
   1). two
   1). two
   ...

5. E

   A java.lang.NullPointerException is thrown.

Reveal answer details Close answer details

Correct answerD

Question 2

Single choice

What makes Java dynamic?

1. A

   At runtime, classes are loaded as needed, and new code modules can be loaded on demand.

2. B

   The runtime can process machine language sources as well as executables from different language

   compilers.

3. C

   The Java compiler uses reflection to test if class methods are supported by resources of a target platform.

4. D

   The Java compiler preprocesses classes to run on specific target platforms.

Reveal answer details Close answer details

Correct answerA

Question 3

Single choice

Which is the correct order of possible statements in the structure of a Java class file?

1. A

   class, package, import

2. B

   package, import, class

3. C

   import, package, class

4. D

   package, class, import

5. E

   import, class, package

Reveal answer details Close answer details

Correct answerD

Explanation

References:
https://www.studytonight.com/java/package-in-java.php

Question 4

Multiple choice

Which two statements are correct about modules in Java? (Choose two.)

1. A

   java.base exports all of the Java platforms core packages.

2. B

   module-info.java can be placed in any folder inside module-path.

3. C

   A module must be declared in module-info.java file.

4. D

   module-info.java cannot be empty.

5. E

   By default, modules can access each other as long as they run in the same folder.

Reveal answer details Close answer details

Correct answersC, E

Explanation

References:
http://tutorials.jenkov.com/java/modules.html

Question 5

Single choice

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

1. A

   java, jdeps

2. B

   javac, jlink

3. C

   jar, jlink

4. D

   javac, jar

Reveal answer details Close answer details

Correct answerC

Explanation

References:
https://blogs.oracle.com/jtc/automating-the-creation-of-jdk9-reduced-runtime-images-in-netbeans

Question 6

Single choice

Given:

What is the result?

1. A

   null

2. B

   nothing

3. C

   It fails to compile.

4. D

   java.lang.IllegalAccessException is thrown.

5. E

   Student

Reveal answer details Close answer details

Correct answerC

Question 7

Multiple choice

Which two commands are used to identify class and module dependencies? (Choose two.)

1. A

   jmod describe

2. B

   java Hello.java

3. C

   jdeps --list-deps

4. D

   jar --show-module-resolution

5. E

   java --show-module-resolution

Reveal answer details Close answer details

Correct answersC, E

Explanation

References:
https://docs.oracle.com/en/java/javase/11/tools/jdeps.html#GUID-A543FEBE-908A-49BF-996C-39499367ADB4

Question 8

Multiple choice

Given:

Which two lines can replace line 1 so that the Y class compiles? (Choose two.)

1. A

   map.forEach((k, v) -> set(v)));

2. B

   set(map.values());

3. C

   super.set(List<String> map)

4. D

   super.set(map.values());

5. E

   set(map)

Reveal answer details Close answer details

Correct answersB, D

Question 9

Single choice

Given:

It is required that if p instanceof Pair then p.isValid() returns true.

Which is the smallest set of visibility changes to insure this requirement is met?

1. A

   setLeft and setRight must be protected.

2. B

   left and right must be private.

3. C

   isValid must be public.

4. D

   left, right, setLeft, and setRight must be private.

Reveal answer details Close answer details

Correct answerB

Question 10

Single choice

Given:

What is the result?

1. A

   watermelon
   orange
   lemon
   grape
   apricot
   apple

2. B

   nothing

3. C

   apple
   apricot
   grape
   lemon
   orange
   watermelon

4. D

   apple
   orange
   grape
   lemon
   apricot
   watermelon

Reveal answer details Close answer details

Correct answerA

Explanation

Question 11

Single choice

Given:

Which is true?

1. A

   The code compiles but does not print any result.

2. B

   The code prints 25.

3. C

   The code does not compile.

4. D

   The code throws an exception at runtime.

Reveal answer details Close answer details

Correct answerC

Question 12

Single choice

Given:

What is the result?

1. A

   Joe
   Marry

2. B

   Joe
   null

3. C

   null
   null

4. D

   null
   Mary

Reveal answer details Close answer details

Correct answerD

Explanation

Question 13

Multiple choice

Given:

Which two methods modify field values? (Choose two.)

1. A

   setAllCounts

2. B

   setACount

3. C

   setGCount

4. D

   setCCount

5. E

   setTCount

Reveal answer details Close answer details

Correct answersB, E

Question 14

Single choice

Given the code fragment:

What is the result?

1. A

   23

2. B

   12

3. C

   123

4. D

   13

Reveal answer details Close answer details

Correct answerA

Explanation

Question 15

Single choice

Given the code fragment:

What is the result?

1. A

   ab cd ef

2. B

   An ArrayIndexOutOfBoundsException is thrown at runtime.

3. C

   The compilation fails.

4. D

   abc def

5. E

   ad be cf

Reveal answer details Close answer details

Correct answerD