Core Java - Interview Questions and Answers for 'Default value' | Search Interview Question

Core Java - Interview Questions and Answers for 'Default value' - 5 question(s) found - Order By Rating

Q1. What will we get if we try to print local variable that hasn't been initialized ?

Core Java

Ans. It will print the garbage value as compiler doesn't provide a default value to local variables.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve local variable default values basic}

Q2. What are the default or implicitly assigned values for data types in java ?

Ans. boolean ---> false
byte ----> 0
short ----> 0
int -----> 0
long ------> 0l
char -----> /u0000
float ------> 0.0f
double ----> 0.0d
any object reference ----> null

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java data types default values}

Try 1 Question(s) Test

Q3. Why do member variables have default values whereas local variables don't have any default value ?

Core Java

Ans. member variable are loaded into heap, so they are initialized with default values when an instance of a class is created. In case of local variables, they are stored in stack until they are being used.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java jvm memory management variables stack memory heap memory default values expert}

Q4. Variable of the boolean type is automatically initialized as?

Core Java

Ans. The default value of the boolean type is false.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java data type boolean initialization default object construction default constructor default value}

Q5. What will be the output of following code ?

public static void main(String[] args)
{
int x = 10;
int y;
if (x < 100) y = x / 0;
if (x >= 100) y = x * 0;
System.out.println("The value of y is: " + y);
}

Ans. The code will not compile raising an error that the local variable y might not have been initialized. Unlike member variables, local variables are not automatically initialized to the default values for their declared type.

Help us improve. Please let us know the company, where you were asked this question :

_{Like Discuss Correct / Improve java code default value}

Q6. What will be the output of following ?

public class BuggyBread {

   private int x;
   private Integer y;

   BuggyBread(int x,int y){};

   public static void main(String[] args){
      BuggyBread buggybread = new BuggyBread(1,2);
      System.out.println(buggybread.x);
      System.out.println(buggybread.y);
   }
}    Reference

Core Java

a. 0 0

b. 0 null

c. null 0

d. null null

Ans.b. 0 null

Search Interview Questions

Help us and Others Improve. Please let us know the questions asked in any of your previous interview.