Programming Final
What is y after the following statement is executed? x = 0; y = (x>0)? 10: -10;
-10
-24 % 5 is
-2
-15 % -4 is
-3
-15 % 4 is_____
-3
-24 % -5 is
-4
What is the result of 45/4?
11
Given the following method static void nPrint(String message, int n){ while(n>0){ System.out.print(message); n--; } } what is k after involving nPrint(" A message", k)? int k = 2; nPrint("A message", k);
2
A variable or a valu listed in a call to method is called_____
An argument
System analysis seeks to analyze the data flow and to identify the systems input and output. When you do analysis, it helps to identify what the output is first, and then figure out what input data you need in order to produce the output
Analysis
Which of the following statements is true
A java applet can be executed from a Web browser
_______provides an integrated development environment(IDE) for rapidly developing Java programs. Editing, compiling, building, debugging, and online help are integrated in one graphical user interface
Java IDE
__________consists of a set of separate programs for developing and testing Java programs, each of which is invoked from a command line.
Java JDK
Java compiler translates Java source code into_______
Java bytecode
________is a technical definition of the language that includes the syntax and semantics of the Java programming language
Java language specification
_________is a software that interprets Java bytecode
Java virtual machine
Suppose you define a Java class as follows: public class Test{ } In order to compile this program, the source code should be stored in a file named___________
Test.java
In java, the word true is
a Boolean literal
Every statement in java ends with________
a semicolon (;)
Each time a method is invoked, the system stores parameters and local variables in an area of memory, known as __________, which stores elements in last-in-first-out fashion
a stack
_______is a simple but incomplete version of a method
a stub
Java______can run from a Web browser
applets
If you attempt to add an int, a byte, a long, and a double, the result will be a ____value
double
The client can use a method without knowing how it is implemented. The details of the implementation are encapsulated in the method and hidden from the client who invokes the method. This is known as______
encapsulation
To declare a constant MAX_LENGTH inside a method with value 99.98, you write____
final double MAX LENGTH =99.98
To declare a constant PI, you write______
final double PI= 3.14159;
Which of the following assignment statements is illegal?
float f = 34.0;
The speed of the CPU may be measured in______
gigahertz
Programming style is important, because_______
good programming style helps reduce programming errors
To declare an int variable number with initial value 2, you write_____
int number = 2
To declare an int variable x with initial value 200, you write____
int x = 200;
Given the following method static void nPrint(String message, int n){ while(n>0){ System.out.print(message); n--; } } What is the printout of the call nPrint('a',4)"?
invalid call
You use____to run a Java program
java
Which JDK command is correct to run a Java application in ByteCode.class?
java ByteCode
The JDK command to compile in the file Test.java is______
javac Test.java
The command to compile a class in the file Test.java is______
javac Test.java
Variables defined inside a method are called______
local variables
Which of these data types requires the most amount of memory
long
Computer can execute the code in__________
machine language
The signature of a method consists of________
method name and parameter list
Any assignment can be used as an assignment expression
true
If a method does not contain any parameters, you must invoke it with a pair of empty parentheses
true
Java is an object-oriented programming language.
true
Java was originally developed by a team led by James Gosling at Sun Microsystems
true
System.exit(0) can be used to terminate the program
true
The keywords in Java are all in lowercase
true
The public classname must be the same as the filename that contains the class
true
The result of an integer division is the integer part of the division; the fraction part is truncated
true
What is 1 + 1 + 1 + 1 + 1 ==5?
true
What is the value of the following expression? true || true && false
true
You can always assign a value of int type to a variable of long type without loss of information
true
You can always convert a switch statement to an equivalent if statement
true
You may have a return statement in a void method.
true
You must have a return statement in a non-void method
true
you may have a return statement in a void method
true
Suppose your method does not return any value, which of the following keywords can be used as a return type?
void
Given |x-2| <=4, which of the following is true?
x-2 <=4 && x-2 >=-4
Given |x-2| >=4, which of the following is true
x-2 >=4 || x-2<= -4
Analyze the following code int x = 0; int y = ((x<100) && (x >0))? 1: -1;
y becomes -1 after the code is executed
The expression (int)(76.0252175*100)/100 evaluates to
76
one byte has_______bits
8
The "less than or equal to" comparison operator in Java is
<=
The assignment operator in Java is____
=
Which of the following operators are right-associative
=
_________is the java assignment operator
=
The equal comparison operator in Java is
==
_______is the brain of the computer
A CPU
Which of the following are storage devices
all of the above
Which of the following expressions evaluates to true?
'a' > 'A'
Which of the following is the correct expression that evaluates to true if the number x is between 1 and 100 or the number is negative
((x<100) && (x>1)) || (x<0)
Which of the following is the correct expression that evaluates to true if the number x is between 1 and 100 or the number is negative?
((x<100) && (x>1)) || (x<0)
Which of the following statements are the same? (A) x -= x+4 (B) x = x + 4 - x (C) x = x - (x +4)
(A) and (C) are the same
Which of the following is the best for generating random integer 0 or 1?
(int)(Math.random() + 0.5)
Which of the following lines is not a java comment?
**comment** --comments
The order of the precedence (from high to low) of the operators binary +, *, &&, ||, & is
*, +, &, &&, ||
The extension name of a Java bytecode file is______
.class
The extension name of java source code file is____
.java
-5 % 5 is
0
25 % 1 is______
0
5 % 1 is______
0
5 % 5 is
0
Suppose x = 0 and y = 0. What is x after evaluating the expression (y>0) && (1>x++)?
0
Suppose x is 1. What is x after x -=1?
0
What is (int)Math.random()?
0
5 % 4 is ______
1
What is 1 % 2?
1
Math.pow(4, 1/2) returns______
1.0
Suppose x =10 and y =10. What is x after evaluating the expression (y >10) && (x++>10)?
10
Supposed x=10 and y = 10. What is x after evaluating the expression (y>10) && (x-->10)?
10
Which of the following are the reserved words?
all of the above
Math.pow(4, 1.0/2) returns______
2.0
What is the value of (double) 5/2?
2.5
The expression 4 + 20/(3-1)*2 is evaluated to
24
Supposed x is 1. What is x after x + =2?
3
What is x after evaluating the following? x = (2>3) ? 2:3
3
Four bytes have_____bits
32
Which of the following expression results in a value 1?
37 % 6
24 % 5 is
4
Which of the following are not valid assignment statements>
55 = x
(Int)('a' + Math.random() * ('z'-'a' + 1)) returns a random number
Between(int)'a' and (int)'z'
Analyze the following code. I. public class Test { public static void main(String[] args){ System.out.println("Welcome to Java!"); } } II. public class Test { public static void main(String[] args) {System.out.println("Welcome to Java!");}}
Both I an II can compile and run and display Welcome to Java, but the code in II has a better style than I.
Which of the following statements is correct?
Every statement in a program must end with a semicolon
_________is the physical aspect of the computer that can be seen
Hardware
Which of the following code has the best style? I. public class Test{ public static void main(String[] args){ System.out.println("Welcome to Java!"); } } II. public class Test{ public static void main(String[] args){ System.out.println("Welcome to Java!"); } } III. public class Test{ public static void main(String[] args){ System.out.println("Welcome to Java!"); } } IV. public class Test{ public static void main(String[] args){ System.out.println("Welcome to Java!"); } }
IV
__________is an object-oriented programming language.
Java
_________is interpreted
Java
_______is Architecture-Neutral
Java
_________contains predefined classes and interfaces for developing Java programs.
Java API
What is k after the following block executes? { Int k = 2; NPrint("a message", k); } System.out.println(k);
K is not defined outside the block. So, the program has a compile error
Which of the following is a constant, according to Java naming conventions?
MAX_VALUE
pow is a method in the ____class
Math
The ______method returns a raised to the power b
Math.pow(a,b)
Java allows you to declare methods with the same name in a class. This is called_____
Method overriding
____is a device to connect a computer to a local area network (LAN)
NIC
Does the method call in the following method cause compile errors? public static void main(String[] args){ Math.pow(2,4); }
No
Does the return statement in the following method cause compile errors? public static void main(String[] args){ int max = 0 if(max! = 0) system.out.println(max); else return; }
No
__________is a program that runs on a computer to manage and control a computer's activities
Operating System
Variables defined in the method header are called_____
Parameter
Arguments to methods allows appear within_____
Parentheses
_________are instructions to the computer
Programs
____________is the code with natural language mixed with Java code
Pseudocode
_______are secondary storage
RAM
Java was developed by______
Sun Microsystems
The____method immediately terminates the program
System.exit(0);
Which of the following statements is correct to display Welcome to Java on the console?
System.out.println(Welcome to Java");
Analyze the following code. public class Test{ public static void main(String[] args){ System.out.println(max(1,2)); } Public static double max(int num1, double num2){ System.out.println("max(int,double) is invoked"); If(num1>num2) Return num1; Else Return num2; } Public static double max(double num1, int num2){ System.out.println("max(double, int) is invoked"); If (num1>num2) Return num1; Else Return num2; } }
The program cannot compile because you cannot have the print statement in a non-void method.
Analyze the following code: public class Test{ public static void main(String[] args){ System.out.println(xMethod(5, 500L)); } public static int xMethod(int n, long 1){ System.out.println("int, long"); return n; } public static long xMethod(long n, long 1){ System.out.println("long, long"); return n; } }
The program displays int, long followed by 5
Analyze the following code: class Test { public static void main(String[] args) { System.out.println(xmethod(5)); } public static int xmethod(int n, long t) { System.out.println(ʺintʺ); return n; } public static long xmethod(long n) { System.out.println(ʺlongʺ); return n; } }
The program displays long followed by 5
Analyze the following code. public class Test { public static void main(String[] args) { System.out.println(m(2)); } public static int m(int num) { return num; } public static void m(int num) { System.out.println(num); } }
The program has compile error because the two methods m have the same signature
_____is to implement one method in the structure chart at a time from the top to the bottom
Top-down approach
A call for the method with a void return type is always a statement itself, but a call for the method with a non-void return type can be treated as either a statement or an expression
True
A method can be declared with no parameters
True
Methods can be declared in any order in a class
True
The actual parameters of a method must match the formal parameters in type, order, and number
True
The modifiers and return value type do not contribute toward distinguishing one method from another, only the parameter list
True
You can define two methods in the same class with the same name and parameters list
True
Which of the following is not an advantage of using methods?
Using methods makes programs run faster
A______mehod does not return a value
Void
public class Test { public static void main(String[] args) { System.out.print(ʺThe grade is ʺ + getGrade(78.5)); System.out.print(ʺ\nThe grade is ʺ + getGrade(59.5)); } public static ________ getGrade(double score) { if (score >= 90.0) return ʹAʹ; else if (score >= 80.0) return ʹBʹ; else if (score >= 70.0) return ʹCʹ; else if (score >= 60.0) return ʹDʹ; else return ʹFʹ; }
Void
A return statement without any values can be used in______
Void method
________is an operating system
Windows XP
Are the following four statements equivalents? number += 1; number=number +1, number++; ++number;
Yes
If you forget to put a closing quotation mark on a string, what kind error will be raised?
a compilation error
__________translates high-level language program into machine language program
a compiler
a variable that is declared inside a method is called__________variable
a local
A variable defined inside a method is referred to as_________
a local variable
If a program compiles fine, but it produces incorrect result, then the program suffers______
a logic error
Why do computers use zeros and ones?
because digital devices have two stable states and it is natural to use one state for 0 and the other for 1
(char)('a' + Math.random()*('z' - 'a' + 1)) returns a random character
between 'a' and 'z'
(int)(Math.random()*(65535+1)) returns a random number_________
between 0 and 65535
A block is enclosed inside______
braces
Which of theses data types requires the least amount of memory
byte
The________loads Java bytecode to the memory
class loader
To improve readability and maintainability, you should declare_____instead of using literal values such as 3.14159
constants
A java interpreter is a program that translates Java source code into Java bytecode
false
A variable may be assigned by a value only once in the program
false
Each Java class must contain a main method
false
In a switch statement, the default case must appear last among all cases. Otherwise, it would result in a compilation error
false
Java source code can be executed on a Java Virtual Machine
false
The assignment operator = is left-associative
false
The break keyword must be used in a switch statement; otherwise, a syntax error occurs.
false
The compiler generates bytecode even if the program has syntax errors
false
The default case must be specified in a switch statement
false
The exclusive or (^) of true and true is true
false
The signature of a method consists of the method name, parameter list and return type
false
You can always assign a value of long type to a variable of int type without loss of precision
false
You can cast a Boolean value to an int, or an int to a Boolean
false
You can define a constant twice in a block
false
You can define a variable twice in a block
false
You can redeclare the variable if it is declared in the method signature
false
a method can be defined inside a method in Java
false
Which of the following code displays the area of a circle if the radius is positive?
if (radius >0) System.out.println(radius * radius * 3.14159);
Suppose isPrime is a boolean variable which of the following is the correct and best statement for testing if isPrime is true?
if(isPrime)
Suppose cond1 and cond2 are two Boolean expressions. When will this if condition be true? if (cond1 && cond2)....
in case cond1 is true and cond2 is true
When you invoke a method with a parameter, the value of the argument is passed to the parameter. This is referred to as________
pass by value
All java applications must have a method_____
public static void main(String[] args)
The main method header is written as______
public static void main(String[] args)
_________is a formal process that seeks to understand the problem and document in detail what the software system needs to do
requirements specification
A java statement ends with a
semicolon
The compiler checks______
syntax errors
The conditional operator? : is a
ternary operator
The System.currentTimeMillis() returns______
the current time in milliseconds since midnight, January 1, 1979 GMT (the Unix time)
A java application must have a main method
true
A java program block starts with an open brace ({) and ends with a closing brace (})
true
A variable must be declared before it can be used
true
You should fill in the blank in the following code with __. public class Test { public static void main(String[] args) { System.out.print("The grade is "); printGrade(78.5); System.out.print("The grade is "); printGrade(59.5); } public static __________ printGrade(double score) { if (score >= 90.0) { System.out.println('A'); } else if(score>= 80.0){ System.out.println('B'); } else if(score>= 70.0){ System.out.println('c'); } else if(score>= 60.0){ System.out.println('D'); } else{ System.out.println('F'); } } }
void
Which of the following should be defined as a void method?
write a method that prints integers from 1 to 100
Assume x = 4, which of the following is true?
x ! = 5
Assume x = 4 and y = 5 which of the following is true
x !=4 ^ y ==5
Assume x = 4 and y = 5, which of the following is true
x < 5 || y < 5
To assign a double variable d to a float variable x, you write____
x = (float)d;
to assign a value 1 to variable x, you write___
x = 1
What is x after the following statements int x = 1; x * = x+1;
x is 2
What is x after the following statements? int x = 2; int y = 1; x *= y + 1;
x is 4