Deck 6: Methods: a Deeper Look

Question 1

Which is a correct static method call of Math class method sqrt?

A) sqrt(900);
B) math.sqrt(900);
C) Math.sqrt(900);
D) Math math = new Math(); math.sqrt(900);

Answer 1

C

Question 2

Consider the following Java statements:
int x = 9;
Double y = 5.3;
Result = calculateValue(x, y);
Which of the following statements is false?

A) A method is called with its name and parentheses.
B) x and y are parameters.
C) Copies of x and y are passed to the method calculateValue.
D) x and y are arguments.

Answer 2

x and y are parameters.

Question 3

Which of the following can be an argument to a method?

A) Constants.
B) Variables.
C) Expressions.
D) All of the above.

Answer 3

D

Question 4

Stacks are known as ________ data structures.

A) FIFO.
B) FILO.
C) LIFO.
D) LILO.

Question 5

When an object is concatenated with a String, ________.

A) a compilation error occurs
B) a runtime error occurs
C) the object's toString method is implicitly called to obtain the String representation of the object
D) the object's class name is concatenated with the String

Question 6

Which of the following promotions of primitive types is not allowed to occur?

A) char to int.
B) double to float.
C) int to double.
D) short to long.

Question 7

The parameter list in the method header and the arguments in the method call must agree in:

A) number
B) type
C) order
D) all of the above

Question 8

Which operator can be used in string concatenation?

A) *
B) +=
C) ++
D) =+

Question 9

Any field declared with keyword ________ is constant.

A) static
B) const
C) constant
D) final

Question 10

Which of the following methods is not in the Math class?

A) ceil
B) abs
C) parseInt
D) log

Question 11

Variables should be declared as fields only if ________.

A) they are local variables
B) they are used only within a method
C) they are required for use in more than one method or their values must be saved between calls to the class's methods
D) they are arguments

Question 12

Method log takes the logarithm of its argument with respect to what base?

A) 10
B) e
C) 2
D) pi

Question 13

To declare a method as static, place the keyword static before ________ in the method's declaration.

A) the method modifier
B) the return type
C) the method name
D) the argument list

Question 14

If more method calls occur than can have their activation records stored on the program execution stack, an error known as a ________ occurs.

A) stack overflow.
B) stack rewind.
C) stack full.
D) stack empty.

Question 15

Declaring main as static allows the JVM to invoke main ________.

A) without knowing the name of the class in which main is declared.
B) by creating an object of the class in which main is declared.
C) without creating an instance of the class in which main is declared.
D) None of the above.

Question 16

A static method can ________.

A) call only other static methods of the same class directly
B) manipulate only static fields in the same class directly
C) be called using the class name and a dot (.)
D) All of the above.

Question 17

Which of the following primitive types is never promoted to another primitive type?

A) double.
B) byte.
C)
C) boolean.
D) Both a and

Question 18

A well-designed method ________.

A) performs multiple unrelated tasks
B) repeats code found in other methods
C) contains thousands of lines of code
D) performs a single, well-defined task

Question 19

Which of the following statements is false?

A) If a method does not return a value, the return-value-type in the method declaration can be omitted.
B) Placing a semicolon after the right parenthesis enclosing the parameter list of a method declaration is a syntax error.
C) Redeclaring a method parameter as a local variable in the method's body is a compilation error.
D) Forgetting to return a value from a method that should return a value is a compilation error.

Question 20

Information is passed to a method in ________.

A) the method name
B) that method's return
C) the method body
D) the arguments to the method

Question 21

An overloaded method is one that ________.

A) has a different name than another method, but the same parameters
B) has the same name as another method, but different parameters (by number, types or order of the types)
C) has the same name and parameters as a method defined in another class
D) has the same name and parameters, but a different return type as another method

Question 22

A Java class can have which of the following methods?
A. void foo(int a)
B. void foo(int a, int b)
C. void foo(double a)
D. void foo(double a, double b)
E. void foo(int b)

A) All of the above.
B) A, B, D, E.
C) A, B, C, D.
D) A, C, D, E.

Question 23

Which statement below could be used to simulate the outputs of tossing a quarter to get heads or tails? Suppose randomNumbers is a SecureRandom object.

A) randomNumbers.nextInt(7);
B) randomNumbers.nextInt(2);
C) randomNumbers.nextInt(1);
D) randomNumbers.nextInt(25);

Question 24

Overloaded methods always have the same _________.

A) method name
B) return type
C) number of parameters
D) order of the parameters

Question 25

Which of these statements best defines scope?

A) Scope refers to the classes that have access to a variable.
B) Scope determines whether a variable's value can be altered.
C) Scope is the portion of a program that can refer to an entity by its simple name.
D) Scope allows the programmer to use a class without using its fully qualified name.

Question 26

The jjava.text package contains classes for manipulating all of the following items except ________.

A) classes
B) numbers
C) strings
D) characters

Question 27

Identifiers in Java have ________ and ________ scopes?

A) method, class.
B) class, block.
C) block, statement.
D) statement, file.

Question 28

Which of the following statements is false?

A) The Java API consists of packages.
B) The Java API helps programmers avoid "reinventing the wheel."
C) The Java API consists of import declarations.
D) None of the above.

Question 29

Which statement below could be used to simulate the outputs of rolling a six-sided die? Suppose randomNumbers is a SecureRandom object.

A) 1 + randomNumbers.nextInt(6);
B) 1 + randomNumbers.nextInt(2);
C) 6 + randomNumbers.nextInt(1);
D) 3 + randomNumbers.nextInt(3);

Question 30

A set of named constants that start with the value 0 for the first constant and increment by 1 for each subsequent constant can be declared as a(n) ________.

A) class
B) enum
C) enumeration
D) None of the above.

Question 31

Which statement creates a random value from the sequence 2, 5, 8, 11 and 14. Suppose randomNumbers is a SecureRandom object.

A) 2 + 5 * randomNumbers.nextInt(3);
B) 3 + 2 * randomNumbers.nextInt(5);
C) 5 + 3 * randomNumbers.nextInt(2);
D) 2 + 3 * randomNumbers.nextInt(5);

Question 32

In a class containing methods with the same name, the methods are distinguished by ________.

A) Number of arguments
B) Types of arguments
C) Return type
D) (a) and (b)
E) (b) and (c)

Question 33

Math static method random generates a random double value in the range from 0.0

A) up to but not including 1.0
B) up to and including 1.0
C) up to and including 100.0
D) up to but not including 100.0

Question 34

Which of the following statements describes block scope?

A) It begins at the opening { of the class declaration and terminates at the closing }.
B) It limits label scope to only the method in which it is declared.
C) It begins at the identifier's declaration and ends at the terminating right brace (}).
D) It is valid for one statement only.

Question 35

Method calls cannot be distinguished by ________.

A) method name
B) return type
C) parameter lists
D) method signature

Question 36

Which of the following is not a package in the Java API?

A) java.component
B) java.awt.event
C) javax.swing.event
D) java.lang

Question 37

Which of the following methods are overloaded with respect to one another? public int max (int a, int b) { … }
Public double max (double a, double b) { … }
Public int max (int a, int b, int c) { … }
Public double max (double a, double b, double c) { … }

A) A and B are overloaded; C and D are overloaded.
B) A and C are overloaded; B and D are overloaded.
C) A, B and C are overloaded.
D) All four methods are overloaded.

Question 38

The identifiers in an enumeration ________.

A) must be unique.
B) may be duplicated.
C) must be lowercase letters and cannot contain numbers.
D) must be uppercase letters and cannot contain numbers.