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    • Java String Basics

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    Question 1

    What is the correct way to declare a String in Java?

    • A

      String str = new String('Hello');

    • B

      String str = new String("Hello");

    • C

      String str = String("Hello");

    • D

      String str = Hello;

    Question 2

    What will be the output of the following code?

    Java 
    String s1 = new String("Java");
String s2 = new String("Java");
System.out.println(s1 == s2);
    • A

      true

    • B

      false

    • C

      Compilation Error


    • D

      Runtime Exception

    Question 3

    How can you make String mutable in Java?

    • A

      Using StringBuilder or StringBuffer

    • B

      Using final keyword

    • C

      By modifying the existing String object

    • D

      By using String.concat()

    Question 4

    How does the intern() method affect Strings in Java?

    • A

      It removes duplicate Strings from memory

    • B

      It ensures that the String is stored in the String Pool

    • C

      It modifies the original String

    • D

      It converts the String into a StringBuffer

    Question 5

    What is the advantage of using String over StringBuilder in multi-threaded applications?

    • A

      String is faster than StringBuilder


    • B

      String is synchronized

    • C

      String is immutable and therefore thread-safe

    • D

      String can be modified in place


    Question 6

    What is the default value of a String variable in Java?


    • A

      ""

    • B

      null

    • C

      " "

    • D

      undefined

    Question 7

    Why are strings immutable in Java?

    • A

      To enable multiple inheritance

    • B

      To avoid garbage collection

    • C

      For security and thread safety

    • D

      All of the above

    Question 8

    Which operator is used for string concatenation?


    • A

      +

    • B

      &

    • C

      .

    • D

      *

    Question 9

    Which of the following is a correct way to concatenate strings?


    • A

      "Hello" + "World"

    • B

      "Hello".concat("World")

    • C

      Both a and b

    • D

      Hello + World

    Question 10

    What happens when you concatenate two strings in Java?

    • A

      A new object is created

    • B

      The original string is changed

    • C

      Compile-time error

    • D

      JVM crashes

    There are 10 questions to complete.

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