Java Questions & Answers – String Comparison

This section of our 1000+ Java MCQs focuses on String comparision in Java Programming Language.

1. Which of these method of class String is used to compare two String objects for their equality?
a) equals()
b) Equals()
c) isequal()
d) Isequal()
View Answer

Answer: a
Explanation: None.

2. Which of these methods is used to compare a specific region inside a string with another specific region in another string?
a) regionMatch()
b) match()
c) RegionMatches()
d) regionMatches()
View Answer

Answer: d
Explanation: None.

3. Which of these method of class String is used to check weather a given object starts with a particular string literal?
a) startsWith()
b) endsWith()
c) Starts()
d) ends()
View Answer

Answer: a
Explanation: Method startsWith() of string class is used to check whether the String in question starts with a specified string. It is specialized form of method regionMatches()

4. What is the value returned by unction compareTo() if the invoking string is less than the string compared?
a) zero
b) value less than zero
c) value greater than zero
d) None of the mentioned
View Answer

Answer: b
Explanation: compareTo() function returns zero when both the strings are equal, it returns a value less than zero if the invoking string is less than the other string being compared and value greater than zero when invoking string is greater than the string compared to.

5. Which of these data type value is returned by equals() method of String class?
a) char
b) int
c) boolean
d) All of the mentioned
View Answer

Answer: d
Explanation: equals() method of string class returns boolean value true if both the string are equal and false if they are unequal.

6. What is the output of this program?

  1.     class output {
  2.         public static void main(String args[])
  3.         { 
  4.            String c = "Hello i love java";
  5.            boolean var;
  6.            var = c.startsWith("hello");
  7.            System.out.println(var);
  8.         }
  9.     }

a) true
b) false
c) 0
d) 1
View Answer

Answer: b
Explanation: startsWith() method is case sensitive “hello” and “Hello” are treated differently, hence false is stored in var.
Output:
$ javac output.java
$ java output
false

7. What is the output of this program?

  1.     class output {
  2.         public static void main(String args[])
  3.         { 
  4.            String s1 = "Hello i love java";
  5.            String s2 = new String(s1);
  6.            System.out.println((s1 == s2) + " " + s1.equals(s2));
  7.         }
  8.     }

a) true true
b) false false
c) true false
d) false true
View Answer

Answer: d
Explanation: The == operator compares two object references to see whether they refer to the same instance, where as equals() compares the content of the two objects.
Output:
$ javac output.java
$ java output
false true

8. What is the output of this program?

  1.     class output {
  2.         public static void main(String args[])
  3.         { 
  4.            String s1 = "Hello";
  5.            String s2 = new String(s1);
  6.            String s3 = "HELLO";
  7.            System.out.println(s1.equals(s2) + " " + s2.equals(s3));
  8.         }
  9.     }

a) true true
b) false false
c) true false
d) false true
View Answer

Answer: c
Explanation: None.
Output:
$ javac output.java
$ java output
true false

9. What is the output of this program?

  1.     class output {
  2.         public static void main(String args[])
  3.         {
  4.             char ch;
  5.             ch = "hello".charAt(1);
  6.             System.out.println(ch);
  7.         }
  8.    }

a) h
b) e
c) l
d) o
View Answer

Answer: b
Explanation: “hello” is a String literal, method charAt() returns the character specified at the index position. Character at index position 1 is e of hello, hence ch contains e.
output:
$ javac output.java
$ java output
e

10. What is the output of this program?

  1.     class output {
  2.         public static void main(String args[])
  3.         {
  4.              String chars[] = {"a", "b", "c", "a", "c"};
  5.              for (int i = 0; i < chars.length; ++i)
  6.                  for (int j = i + 1; j < chars.length; ++j)
  7.                      if(chars[i].compareTo(chars[j]) == 0)
  8.                          System.out.print(chars[j]); 
  9.         }
  10.    }

a) ab
b) bc
c) ca
d) ac
View Answer

Answer: d
Explanation: compareTo() function returns zero when both the strings are equal, it returns a value less than zero if the invoking string is less than the other string being compared and value greater than zero when invoking string is greater than the string compared to.
output:
$ javac output.java
$ java output
ac

Sanfoundry Global Education & Learning Series – Java Programming Language.

About

Manish Bhojasia, a technology veteran with 17+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He is Linux Kernel Developer and SAN Architect and is passionate about competency developments in these areas. He lives in Bangalore and delivers focused training sessions to IT professionals in Linux Kernel, Linux Debugging, Linux Device Drivers, Linux Networking, Linux Storage & Cluster Administration, Advanced C Programming, SAN Storage Technologies, SCSI Internals and Storage Protocols such as iSCSI & Fiber Channel. Stay connected with him below.


Sanfoundry Training Center of Excellence (CoE)

Manish Bhojasia, a technology veteran with 17+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He is Linux Kernel Developer and SAN Architect and is passionate about competency developments in these areas. He lives in Bangalore and delivers focused training sessions to IT professionals in Linux Kernel, Linux Debugging, Linux Device Drivers, Linux Networking, Linux Storage & Cluster Administration, Advanced C Programming, SAN Storage Technologies, SCSI Internals and Storage Protocols such as iSCSI & Fiber Channel. Stay connected with him below.







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