26. Which of this method of class StringBuffer is used to concatenate the string representation to the end of invoking string?

1. 1. join()

   
   
   

   2. concatenate()

   
   
   

   3. append()

   
   
   

   4. concat()

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   append()

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27. Which of these class is used to create an object whose character sequence is mutable?

1. 1. tostring()

   
   
   

   2. String()

   
   
   

   3. StringBuffer()

   
   
   

   4. String() & StringBuffer()

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   StringBuffer represents growable and writable character sequence.

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28. What is the output of this program?
    

    public class Result 
        {
            public static void main(String args[])
            {             String str = "Interview Mania";
                 int K = str.indexOf('v');
                 int L = str.lastIndexOf('i');
                 System.out.print(K + " " + L);
     
            }
       }
    

1. 1. 13 5

   
   
   

   2. 3 5

   
   
   

   3. 5 13

   
   
   

   4. 5 3

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   indexOf() method returns the index of first occurrence of the character where as lastIndexOf() returns the index of last occurrence of the character.

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29. What is the output of this program?
    

    public class Result 
        {
            public static void main(String args[])
            {
               String str1 = "Interview Mania";
               String str2 = str1.substring(0 , 9);
               System.out.println(str2);
            }
       }
    

1. 1. Interview

   
   
   

   2. Mania

   
   
   

   3. Interview Mania

   
   
   

   4. Inter

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   substring(0,9) returns the character from 0 th position to 8th position.

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30. What is the output of this program?
    

    
    public class output 
        {
            public static void main(String args[])
            { 
               String str1 = "Intervzew Manza";
               String str2 = str1.replace('z','i');
               System.out.println(str2);
            }
        }
    

1. 1. Intervzew

   
   
   

   2. Manza

   
   
   

   3. Interview Mania

   
   
   

   4. IntervzewManza

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   replace() method replaces all occurrences of one character in invoking string with another character. str1.replace(‘z’,’i’) replaces every occurrence of ‘z’ in hello by ‘i’, giving Interview Mania.

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