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

Search Interview Questions


 2796 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 'String immutable' - 3 question(s) found - Order By Newest

 Q1. How does making string as immutable helps with securing information ? How does String Pool pose a security threat ?Core Java2017-06-22 11:32:57

Ans. String is widely used as parameter for many java classes, e.g. network connection, opening files, etc. Making it mutable might possess threats due to interception by the other code segment or hacker over internet.

Once a String constant is created in Java , it stays in string constant pool until garbage collected and hence stays there much longer than what's needed. Any unauthorized access to string Pool pose a threat of exposing these values.


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

   Like      Discuss      Correct / Improve     Security  String pool   string immutable      expert        rare


Related Questions

  What are different ways to create String Object? Explain.
  Why Char array is preferred over String for storing password?
  What is a String Pool ?
 Which memory segment holds String Pool in Java ?
 How and Why Strings are interned in Java ?
 What will be the output of following code

Integer x = 1;
Integer y = 2;
System.out.println(x == y);

What if you change 1 to "1" and Integer to String?
 What will be result of following code and why

Integer int1 = 1;
Integer int2 = 1;
String str1 = new String("str");
String str2 = new String("str");
String str3 = "str";
String str4 = "str";

      
System.out.println(int1 == int2);
System.out.println(str1 == str2);
System.out.println(str3 == str4);
 What is the purpose of String Pool ? Don't you think it's a performance overhead to have unnecessary check for string in string pool ?
 Why string pool concept has been introduced in string ?


 Q2. How is string object immutable if we can concat a string to it ?Core Java2017-08-08 09:50:28

Ans. Because it doesn't make the change in the existing string but would create a new string by concatenating the new string to previous string. So Original string won't get changed but a new string will be created. That is why when we say

str1.concat("Hello");

It means nothing because we haven't specified the reference to the new string and we have no way to access the new concatenated string. Accessing str1 with the above code will still give the original string.

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

   Like      Discuss      Correct / Improve     string  string immutable  string concat


Related Questions

  Why is String immutable in Java ?
 How does making string as immutable helps with securing information ? How does String Pool pose a security threat ?
 Why shouldn't we use string concatenation extensively or in a loop ?


 Q3. Why shouldn't we use string concatenation extensively or in a loop ?Core Java2017-08-08 09:52:53

Ans. Because String being an immutable object creates a new object upon each concatenation cycle. If there is any such need , we should use String Builder whose objects are mutable.

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

   Like      Discuss      Correct / Improve     string  string immutable     Ancestry


Related Questions

  Why is String immutable in Java ?
 How does making string as immutable helps with securing information ? How does String Pool pose a security threat ?
 How is string object immutable if we can concat a string to it ?




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: