QUIZ ON : java - JAVA LIBRARY CLASSES

JAVA LIBRARY CLASSES

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Question No# : 01 out of 21

Which among the following class do not belong to the java.lang package?

A. System

B. String

C. Math

D. Scanner

Question No# : 02 out of 21

Which of the following is not a wrapper class?

A. Byte

B. Int

C. Long

D. Float

Question No# : 03 out of 21

Which among the following Scanner methods allows us to input a number with a decimal point?

A. nextInt()

B. nextFloat()

C. nextDecimal()

D. nextPoint()

Question No# : 04 out of 21

Which among the following function returns the absolute value of a number?

A. Math.absoulute( )

B. Math.neutral( )

C. Math.abs( )

D. Math.positive( )

Question No# : 05 out of 21

Which class is inherited by the Character and Boolean wrapper classes?

A. Object

B. Number

C. Both a and b

D. None of these

Question No# : 06 out of 21

What package is a part of the wrapper class which is imported by default into all Java programs?

A. java.util

B. java.lang

C. java.awt

D. None of these

Question No# : 07 out of 21

What is, converting a primitive value into an object of the corresponding wrapper class called?

A. Autoboxing

B. Unboxing

C. Type Casting

D. All of these

Question No# : 08 out of 21

What value will Math.sqrt(Math.ceil(8.1)) return?

A. 9.0

B. 9

C. 3.0

D. 4.0

Question No# : 09 out of 21

What is the return type of Math.min(1,2.0f)?

A. float

B. double

C. int

D. long

Question No# : 10 out of 21

What value will Math.sqrt(-9) return?

A. -3.0

B. 3.0

C. NaN

D. None of these

Question No# : 11 out of 21

If s=“123”, which among the following will convert it to an integer?

A. int a=Integer(s);

B. int a=(int)s;

C. int a=parseInt(s);

D. int a=Integer.parseInt(a);

Question No# : 12 out of 21

Which among the following expression will return a random integer between 5 and 10 both inclusive?

A. 5+(int)(Math.random()*6)

B. 5+(int)(Math.random()*10)

C. 5+Math.random()*6

D. 5+Math.random()*10

Question No# : 13 out of 21

The member ‘out’ object of the ‘System’ class belongs to which class?

A. System

B. Print

C. PrintStream

D. Println

Question No# : 14 out of 21

Which among the following methods return a true or a false?

A. toLowerCase()

B. toUpperCase()

C. parseInt()

D. isUpperCase()

Question No# : 15 out of 21

Which among the following function is equivalent to Math.sqrt(a)?

A. Math.cbrt(a);

B. Math.pow(a,1/2)

C. Math.pow(a,1/2.0);

D. Math.

Question No# : 16 out of 21

Which among the following will yield -1 for negative number and 1 for positive number for a number stored in a variable a?

A. Math.abs(a)*a

B. Math.abs(a) / a

C. Math.ceil(a) / Math.floor(a)

D. None of these

Question No# : 17 out of 21

Which among the following package is imported by default:

A. java.lang

B. java.util

C. Both a and b

D. None of these

Question No# : 18 out of 21

Which among the following function is used to check whether a given character is a tab space or not?

A. isTab()

B. isTabSpace()

C. isSpace()

D. isWhitespace()

Question No# : 19 out of 21

Which among the following is valid character initialisation?

A. Character c=new Character(â€˜câ€™);

B. Character c=new Character(â€œcâ€);

C. Both a and b

D. None of these

Question No# : 20 out of 21

Which of the following is valid method of initialising?

A. Integer a=new (5);

B. Integer a=Integer(5);

C. Integer a=new Integer(5);

D. Integer a=new (â€œ5â€);

Question No# : 21 out of 21

Which among the following gives the next mathematical integer?

A. Math.floor( )

B. Math.ceil( )

C. Math.random( )

D. All of these