APCSA Unit 2 Review

Which data type gets returned from length() method in String class?

• double

• String

• int

• number

String txt = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

What is the correct way to find the length of "txt" string?

• int len = length(txt);

• float len = txt.length();

• int len = txt.length();

• double len = length(txt);

Choose correct purpose of indexOf() in String class.

• returns the index (the position) of the last occurrence of a specified text in a string

• returns the character of the first occurrence of a specified character in a string

• returns the index (the position) of the first occurrence of a specified text in a string (excluding whitespace)

• returns the index (the position) of the first occurrence of a specified text in a string (including whitespace)

What is the output of the following?

String x = "10";

String y = "20";

String z = x + y;

System.out.println(z);

• 1020

• 10 20

• 30

• "10 20"

What will be the output of below code?

String statement = "Outfit of the day";

System.out.println(statement.Substring(3,6));

• it of

• tfit

• fit

• FIT

What is the return type of equals() method?

• int

• String

• char

• boolean

What is the most appropriate way to check if two Strings are identical?

• string1 == string2

• string1.equals(string2)

• string1.same(string2)

• string1.equalsIgnorecase(string2)

(Multiple answer question)

Pick all NON-primitive datatypes from below :

• String

• int

• primitive

• Array

When you try to square root a negative number in Java, what happens?

• It returns the value NaN

• It raises an error

• It returns the value undefined

• It returns an imaginary number

Which Math class method can be used to calculate exponents?

• Math.exponent()

• Math.raise()

• Math.pow()

• Math.ceil()