Core Java - Interview Questions and Answers for 'Stringbuffer' | Search Java Interview Question - javasearch.buggybread.com
Javasearch.buggybread.com
Share

Search Interview Questions


 2720 questions in repository.
 There are more than 200 unanswered questions.
Click here and help us by providing the answer.
 Have a video suggestion.
Click Correct / Improve and please let us know.
Label / Company      Label / Company / Text

   



Core Java - Interview Questions and Answers for 'Stringbuffer' - 13 question(s) found - Order By Newest

Very frequently asked in different variations. Frequently asked in Deloitte ( 2 feedback ) , HCL Tech ( 3 feedback ) and Coginizant (CTS)
  Q1. Explain the scenerios to choose between String , StringBuilder and StringBuffer ?

or

What is the difference between String , StringBuilder and StringBuffer ? 		Core Java
Anonymous
Ans. If the Object value will not change, use String Class because a String object is immutable.

If the Object value can change and will only be modified from a single thread, use StringBuilder because StringBuilder is unsynchronized(means faster).

If the Object value may change, and can be modified by multiple threads, use a StringBuffer because StringBuffer is thread safe(synchronized).

  Sample Code for String

  Sample Code for StringBuffer

  Sample Code for StringBuilder

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


   Like      Discuss      Correct / Improve     java   string class   string   stringbuilder   stringbuffer     Cognizant (CTS)   San Jose State University (SJSU)  HCL Technologies   Deloitte  Sophos  Hitachi  JPMorgan Chase  IBM  Kony Labs  Keystone  ebay  TIAA Financial Services  Ancestry   Rakuten  Accenture      basic        frequent
Try 3 Question(s) Test

Very frequently asked in HCL Tech ( Based of 4 inputs )
  Q2. Write a Program to reverse a string iteratively and recursivelyCore Java

Ans. Using String method -

new StringBuffer(str).reverse().toString();

Iterative -

Strategy - Loop through each character of a String from last to first and append the character to StringBuilder / StringBuffer

public static String getReverseString(String str){
StringBuffer strBuffer = new StringBuffer(str.length);
for(int counter=str.length -1 ; counter>=0;counter--){
strBuffer.append(str.charAt(counter));
}
return strBuffer;
}

Recursive -

Strategy - Call the method with substring starting from 2nd character recursively till we have just 1 character.

public static String getReverseString(String str){
if(str.length <= 1){
return str;
}
return (getReverseString(str.subString(1)) + str.charAt(0);
}

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

   Like      Discuss      Correct / Improve     string  StringBuffer  recursion  for loop  stringbuffer.append  java.lang.String  java.lang.StringBuffer  String Manipulation     HCL Technologies  Ocado  BlackRock  Oracle  FINRA  Arezzo Sky  Zalando  Boeing        frequent

 Q3. Which String class does not override the equals() and hashCode() methods, inheriting them directly from class Object?Core Java
Anonymous
Ans. java.lang.StringBuffer.

  Sample Code for StringBuffer

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

   Like      Discuss      Correct / Improve     java   object class   stringbuffer      expert        rare

Very frequently asked. Usually asked in different variants like Diff between StringBuffer , String Builder ; Difference between StringBuilder and String class; Choice between these classes etc.
  Q4. What is the difference between StringBuffer and String class ?Core Java
Anonymous
Ans. A string buffer implements a mutable sequence of characters. A string buffer is like a String, but can be modified. At any point in time it contains some particular sequence of characters, but the length and content of the sequence can be changed through certain method calls.

The String class represents character strings. All string literals in Java programs, such as "abc" are constant and implemented as instances of this class; their values cannot be changed after they are created.

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

   Like      Discuss      Correct / Improve     java   string   stringbuffer   frequently asked     BlackRock  Synechron  RedMane Technology  Velopsys Technologies   American Express  Sophos  QualiTest  ebay  Infosys Technologies  American Express      basic        frequent
Try 1 Question(s) Test

Very frequently asked. Usually difference between String,StringBuffer and StringBuilder is asked in different variations.
  Q5. Difference between StringBuffer and StringBuilder ?Core Java
Anonymous
Ans. StringBuffer is synchronized whereas StringBuilder is not.

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

   Like      Discuss      Correct / Improve     java   string   stringbuffer   string class   stringbuilder   synchronized   basic interview question   infosys technologies     Thomson Reuters  Ludia  QualiTest  United Health Group (UHG)  Sophos  JPMorgan Chase  ebay  Infosys Technologies  Experian India  HCL Technologies  Symantec  Tata Consultancy (TCS)  Accenture  Infosys  Cerner  Priceline      basic        frequent
Try 1 Question(s) Test

Very frequently asked in HCL Tech ( Based of 4 inputs )
  Q6. Write a program to reverse a string iteratively and recursively ?Core Java
Admin
info@buggybread.com
Ans. Using String method -

new StringBuffer(str).reverse().toString();

Iterative -

public static String getReverseString(String str){
StringBuffer strBuffer = new StringBuffer(str.length);
for(int counter=str.length -1 ; counter>=0;counter--){
strBuffer.append(str.charAt(counter));
}
return strBuffer;
}

Recursive -

public static String getReverseString(String str){
if(str.length <= 1){
return str;
}
return (getReverseString(str.subString(1)) + str.charAt(0);
}

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


   Like      Discuss      Correct / Improve     java   string   reverse   stringbuffer   string class   code     HCL Technologies  Exelis  Mahindra Comviva  Fidelity National Information Services (FIS)   Genpact  Digite Infotech        frequent

 Q7. what will be the output of this code ?

public static void main(String[] args){
   StringBuffer s1=new StringBuffer("Buggy");                       
   test(s1);                    
   System.out.println(s1);              
}       

private static void test(StringBuffer s){      
   s.append("Bread");   
}		Core Java
Admin
info@buggybread.com
Ans.  BuggyBread

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

   Like      Discuss      Correct / Improve     java   code   coding   stringbuffer   string   method calling   pass by reference

 Q8. what will be the output of this code ?

public static void main(String[] args)    {          
   String s1=new String("Buggy");                         
   test(s1);                    
   System.out.println(s1);              
}       

private static void test(StringBuffer s){      
   s.append("Bread");   
}		Core Java
Admin
info@buggybread.com
Ans.  Buggy

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

   Like      Discuss      Correct / Improve     java   code   coding   stringbuffer   string   method calling   pass by reference

 Q9. what will be the output of this code ?

public static void main(String[] args)    {          
   StringBuffer s1=new StringBuffer("Buggy");                         
   test(s1);                    
   System.out.println(s1);              
}       

private static void test(StringBuffer s){      
   s=new StringBuffer("Bread");   
}		Core Java
Admin
info@buggybread.com
Ans.  Buggy

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

   Like      Discuss      Correct / Improve     java   code   coding   stringbuffer   string   method calling   pass by reference


Do you think these are the Best Java Frameworks ?

OpenXavaSPRING MVCApache StripesCheck everything
that is Best in Java

Click Here


 Q10. Can StringBuffer and StringBuilder in Java be inherited?Core Java2017-03-15 13:54:44

Ans. No, they have been declared final and hence cannot be extended.

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

   Like      Discuss      Correct / Improve     StringBuffer  StringBuilder

 Q11. Which of the following class creates immutable objects ?Core Java
a. String
b. StringBuffer
c. StringBuilder
d. None of these create immutable objects.

Ans.a. String
 Q12. Which of the following class is synchronized ?Core Java
a. String
b. StringBuffer
c. StringBuilder
d. None of these

Ans.b. StringBuffer
 Q13. Which of the following class cannot be extended or inherited ?

StringBuffer , StringBuilder		Core Java
a. StringBuffer
b. StringBuilder
c. Both cannot be extended
d. Both can be extended

Ans.c. Both cannot be extended

Subscribe to Java News and Posts. Get latest updates and posts on Java from Buggybread.com
Enter your email address:
Delivered by FeedBurner


comments powered by Disqus
 

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

Any input from you will be highly appreciated and It will unlock the application for 10 more requests.

Company Name:
Questions Asked:
         

X Close this

X Close this

Help Us Improve.
Please share your
interview experience.

Company Name:   


Questions Asked: