Oracle Oracle Database 1Z0-808 Questions & Answers

• Question 1:

  

  Which statement is true about the main() method?

  A. It is invoked by JRE

  B. It is a final method

  C. It returns true if it is executed successfully at run time

  D. It must be defined within a public class

  Correct Answer: A

  Reference: https://www.quora.com/How-does-a-main-method-get-invoked-automatically-explain-it-in-brief

• Question 2:

  Given the code fragment:

  

  What is the result?

  A. S 6

  B. S 5

  C. s-1

  D. w 7

  Correct Answer: A

  Answer is A. Because String str is "Sweet Sweat" not "Sweet sweat"

  String str="Sweet Sweat";

  String str2=str.trim().charAt(6)+" " + str.indexOf("Sw",1);

  System.out.println(str2); // S 6

• Question 3:

  Given the code fragment:

  

  Which code fragment at line 10 prints Welcome 100?

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: B

  

• Question 4:

  Given these requirements:

  1.

  Bus and Boat are Vehicle type classes.

  2.

  The start() and stop() methods perform common operations across the Vehicle class type.

  3.

  The ride() method performs a unique operations for each type of Vehicle.

  Which set of actions meets the requirements with optimized code?

  A. 1. Create an abstract class Vehicle by defining start() and stop() methods, and declaring the ride() abstract method.

  2. Create Bus and Boat classes by inheriting the Vehicle class and overriding the ride() method.

  B. 1. Create an interface Vehicle by defining start() and stop() methods, and declaring the ride() abstract method.

  2. Create Bus and Boat classes by implementing the Vehicle class.

  C. 1. Create an abstract class Vehicle by declaring stop(), start(), and ride() abstract methods.

  2. Create Bus and Boat classes by inheriting the Vehicle class and overriding all the methods.

  D. 1. Create an interface Vehicle by defining default stop(), start(), and ride() methods.

  2. Create Bus and Boat classes by implementing the Vehicle interface and overriding the ride() method.

  Correct Answer: D

• Question 5:

  Given:

  

  What is the result?

  A. myStr: 7007, myNum: 7007

  B. Error

  C. myStr: 9009, myNum: 7007

  D. myStr: 7007, myNum: 9009

  Correct Answer: C

  

• Question 6:

  Given the content of the Customer.java and Trader.java files:

  

  Which two methods can be overridden in the Trader class from the Customer class? (Choose two.)

  A. m2()

  B. m3()

  C. m4()

  D. m1()

  Correct Answer: BD

  B: m3 is protected, but can be accessed if the other class extends the parent class even though it is in a different package.

  D: m1 is public, just by importing the package you can access it normally.

• Question 7:

  Given the code fragment:

  

  Which action enables the code to print Helping... Done?

  A. replace class Humanoid extends Robot { with abstract class Humanoid extends Robot {

  B. replace interface Speakable { with abstract class Speakable

  C. replace public void process(); with public abstract void process();

  D. replace abstract class Robot implements Speakable { with class Robot extends Speakable {

  Correct Answer: C

  

• Question 8:

  Given: What is the result?

  

  A. double sum is 30.0 float sum is 30.0

  B. float sum is 30.0 double sum is 30.0

  C. Integer sum is 30 double sum is 30.0

  D. Integer sum is 30 float sum is 30.0

  Correct Answer: B

  

• Question 9:

  Given: What is the result?

  

  A. c=null b=true f=0.0

  B. c= b=false f=0.0

  C. c=null b=false f=0.0

  D. c=0 b=false f=0.0F

  Correct Answer: C

  

• Question 10:

  Which two code fragments cause compilation errors? (Choose two.)

  A. double y1 = 203.22; float fit = y1;

  B. float fit = (float) 1_11.00;

  C. Float fit = 100.00;

  D. int y2 = 100; float fit = (float) y2;

  E. float fit = 100.00F;

  Correct Answer: AC