Java Middle Exam Answers

Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 2 (Answer all questions in this section) 1. In the code example below, identify any methods: public public public public

class Employee { String name = " Duke"; int empId = 12105; float salary;

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public void displaySalary(){ System.out.println("Employee Salary: "+salary); } } name displaySalary() (*) salary empId Correct 2. There are several fields and methods in a Shirt class. Which of the following could be a method in the Shirt class?

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getShirtSize() (*) price size color Correct 3. You design a Circle class with various fields and methods. Which of the following could be fields in this class? Distinguish which of these are between the properties and behavior. (Choose all correct answers) radius (*) calculateDiameter() color (*) calculateArea() calculateCircumference()

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Correct 4. Code within curly braces is called a “Block of code”.

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True (*) False Correct 5. A Java program can be written in the single line.

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True (*) False Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 2 (Answer all questions in this section) 6. A breakpoint can be set by clicking a number in the left margin of the IDE. Clicking again removes the breakpoint.

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True (*) False Correct 7. Which of the following are adequate definitions for components of the Spiral Model of Development?

(Choose all correct answers) Test: Run the code and verify results (*)

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Design: Plan the approach (*) Develop: Collect all specified instructions Requirements: Start the development Correct 8. The Spiral Model reflects an iterative development process.

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True (*) False Correct 9. A software feature may allow the user to perform a specific task.

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True (*) False Correct

Section 3 (Answer all questions in this section) 10. The Java compiler automatically promotes byte, short, and chars data type values to int data type.

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True (*) False Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer.

(1) Points

Section 3 (Answer all questions in this section) 11. What is the correct way to cast a long to an int?

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int longToInt = (int)20L; (*) int longToInt = 20L; int longToInt = 20L(int); int longToInt = int 20L; Correct 12. What is parsing?

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Converting numeric data to text Converting text to numeric data (*) Converting numeric data to a specified numeric data type Reading text from numeric data Correct 13. What value is assigned to x? int x = 25 - 5 * 4 / 2 - 10 + 4;

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8 9 (*) 34 7 Correct 14. Which keyword makes a variable’s value unchangeable?

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const final (*) static break Correct

15. What is the output? public static void main(String args[]) { int x = 100; int y = x; y++; System.out.println("Value of x is " + x); System.out.println("Value of y is " + y); } Value Value Value Value Value Value Value Value

of of of of of of of of

x y x y x y x y

is is is is is is is is

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0 1 100 1 100 1 100 101 (*)

Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 3 (Answer all questions in this section) 16. In Java, char is a primitive data type, while String is an object data type.

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True (*) False Correct 17. An Object cannot have String objects as properties.

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True False (*) Correct

18. The print() method prints to the console and automatically creates a line.

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True False (*) Correct 19. These two code fragments perform the same task.

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// Fragment 1 String inputString = JOptionPane.showInputDialog("??"); int input = Integer.parseInt(inputString); input++; // Fragment 2 int input = Integer.parseInt(JOptionPane.showInputDialog("??")) + 1; True (*) False Correct 20. Which two statements are true about the Scanner class?

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(Choose all correct answers) A Scanner’s delimiter can be changed. (*) A Scanner object opens a stream for collecting input. (*) A Scanner object doesn’t have fields and methods. Scanners cannot read text files. Incorrect. Refer to Section 3 Lesson 5.

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 3 (Answer all questions in this section)

21. The Scanner class considers space as the default delimiter while reading the input.

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True (*) False Correct 22. What is the output? public class Hello { public static void main(String args[]) { String str = ”Hello”; str = ”World”; System.out.println(str); } }

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Hello Hello World World (*) Hello World Correct 23. Java is a strongly typed language; therefore you must declare a data type for all variables.

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True (*) False Correct 24. Identify the variable declared in the given code. public class Welcome { public static void main(String args[]) { int a = 2; System.out.println("a is" + a); } } int Welcome a (*) 2 Correct

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Section 4 (Answer all questions in this section) 25. The classes of the Java class library are organized into packages.

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True (*) False Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 4 (Answer all questions in this section) 26. Which two are valid import statements of the Scanner class?

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(Choose all correct answers) import java.util; import java.*; import java.util.*; (*) import java.util.Scanner; (*) Correct 27. The import statement consists of two parts. import package.className; One is the package name and the other is the classname. True (*) False

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Correct 28. The JFrame and JOptionPane classes are in the javax.swing package. Which two will import those classes?

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(Choose all correct answers) import javax.swing.*; (*) import javax.swing; import javax.swing.JOptionPane; import javax.swing.JFrame; (*) import javax.swing.J*; Correct 29. The indexOf() method returns the index value of a character in the string.

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True (*) False Correct 30. What is the output?

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public static void main(String args[]) { String greeting = "Java World!"; String w = greeting.substring(7, 11); System.out.println(w); } rld! (*) ld! orld! rld Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer.

(1) Points

Section 4 (Answer all questions in this section) 31. The String class must be imported using java.lang.String;

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True False (*) Correct 32. What is the output? public static void main(String args[]) { String greeting = "Java World!"; String w = greeting.replace("a", "A"); System.out.println(w); }

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JavA World! JAvA World! (*) Java World! JAva World! Correct 33. Which of the following scenarios would be ideal for writing a method?

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When you don’t find similar lines of code to describe an object’s behavior. For every five to six lines of code. To group similar data types together When you don’t want to repeat similar lines of code to describe an object’s behavior. (*) Correct 34. You’re designing banking software and need to store 10000 customer accounts with information on the accountholder’s name, balance, and interest rate. The best approach is store 30000 separate variables in the main method. True False (*) Correct

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35. Methods allow all instance of a class to share same behaviors.

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True (*) False Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 4 (Answer all questions in this section) 36. Which of the following are the arguments in the following method? Employee emp = new Employee(); emp.calculateSalary(100000, 3.2, 15);

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calculateSalary(100000, 3.2, 15); 100000, 3.2, 15 (*) emp emp.calculateSalary(100000, 3.2, 15); Correct 37. You need to generate random integer values in the range 2 through 10. This code fragment will produce the desired result.

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Random r = new Random(); r.nextInt(9) + 2; True (*) False Correct 38. You need to generate random integer values between 0 and 80 (inclusive). Which statement should you use?

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nextInt(81); (*) nextInt(80); nextInt(); nextInt(0-79); Correct 39. Which class is used to generate random numbers?

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Random (*) Number Integer Double Correct 40. The Math class methods can be called without creating an instance of a Math object.

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True (*) False Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 4 (Answer all questions in this section) 41. What is the package name which contains Math class?

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java.awt java.net java.lang (*) java.io

Incorrect. Refer to Section 4 Lesson 5.

Section 5 (Answer all questions in this section) 42. A String comparison with == compares the Strings’ locations in memory and not the content of the String.

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True (*) False Correct 43. What is the output? public static void main(String[] args) { String name = "Java"; String language = "Programming"; String fullName = name + language; boolean test = fullName.equals(name + language); System.out.println(test); }

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False JavaProgramming Java Programming True (*) Correct 44. Which three are conditional statements?

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(Choose all correct answers) switch statement (*) for loop do while loop if/else statement (*) if statement (*) Correct

45. How should Strings be compared?

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The equals() method (*) ~= == = Correct

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Test: Java Foundations Midterm Exam Review your answers, feedback, and question scores below. An asterisk (*) indicates a correct answer. Section 5 (Answer all questions in this section) 46. An employee is eligible for a bonus based on certain criteria. Under what conditions does “Eligible for a bonus” print?

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int rating; int experience; if (rating > 1 && experience == 5) { System.out.println (“Eligible for a bonus”); } 5 experience and 2 or more rating (*) 5 experience and 1 rating Less than 5 experience and 1 rating. 5 rating and 1 experience Correct 47. A customer is eligible for a discount based on certain criteria. Under what conditions does “You qualify for a discount” print? (Hint: There may be more than one correct answer) int purchase; int rewardPoints; if (purchase >= 2000 || rewardPoints >= 4000) { System.out.println("You qualify for discount"); } (Choose all correct answers)

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When rewardPoints is more than 1000 and purchase is 1000 When rewardPoints is more than 2000 or purchase greater than 1000 When purchase is 2000 regardless of the value of rewardPoints (*) When purchase is 4000 and rewardPoints is 2000 (*) Correct 48. Which two are not logical operators?

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(Choose all correct answers) ! || % (*) + (*) && Correct 49. Which two statements are true about the default statement?

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(Choose all correct answers) The default statement is optional in switch statement. (*) A default statement is required in every switch statement. When the input does not match any of the cases, the default statement is executed. (*) A default statement is executed by default when the program is executed. Correct 50. What is the output? char grade = 'A'; switch (grade) { case 'A': System.out.println("Congratulations!"); System.out.println("Good work"); case 'C': System.out.println("Average"); case 'D': System.out.println("Barely passing"); case 'F': System.out.println("Failed"); }

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Failed Congratulations! Congratulations! Good Work Average Barely Passing Failed (*) A Correct

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