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黑墨水鱼
2022-03-10 17:18:03 +08:00
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1
.gitignore vendored Normal file
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*.class

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assignment1/Question1/AutoRobot.java Normal file
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/*
* Authro: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022/03/09
* Description: This is the main class of AutoRobot.
*/
public class AutoRobot {
/**
* current speed of the robot.
*/
private double currentSpeed;
/**
* name of the robot
*/
private String name;
/**
* Constructor for objects of class AutoRobot. Default name is "xyz".
* Initial speed is 0.
*/
public AutoRobot() {
// initialise instance variables
this.currentSpeed = 0;
this.name = "xyz";
}
/**
* Getter method for name.
*
* @return name of the robot.
*/
public String getName() {
return this.name;
}
/**
* Getter method for current speed.
*
* @return current speed of the robot.
*/
public double getCurrentSpeed() {
return this.currentSpeed;
}
/**
* Increase the speed of the robot by 5. The speed exceed 20 will
* print "Dangerous" message and do nothing.
*
* @return current speed of the robot.
*/
public void accelerate() {
if (this.currentSpeed >= 20) {
System.out.println("Dangerous! Please stay within speed limit.");
return;
}
this.currentSpeed += 5;
}
/**
* Decrase the speed of the robot by 5. The speed can not be less than 0.
*
* @return current speed of the robot.
*/
public void brake() {
if (this.currentSpeed - 5 <= 0) {
this.currentSpeed = 0;
return;
}
this.currentSpeed -= 5;
}
/**
* Print out current status.
*
* @return void.
*/
public void printStatus() {
System.out.println(String.format("Hello there, my name is %s and my current speed is %.1f",
this.name, this.currentSpeed));
}
/**
* Setter method for name.
*
* @param name name of the robot.
* @return void.
*/
public void setName(String name) {
this.name = name;
}
/**
* Static test the class AutoRobot.
*
* @return void.
*/
public static void testAutoRobot() {
AutoRobot robot = new AutoRobot();
// print current status
robot.printStatus();
// print true for default value
System.out.println(robot.getName().equals("xyz"));
System.out.println(doubleEquals(robot.getCurrentSpeed(), 0));
System.out.println(robot.getCurrentSpeed() == 0);
// change name and print current status
robot.setName("ABC");
// print true for name
System.out.println(robot.getName().equals("ABC"));
// accelerate and print true for current speed
robot.accelerate();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 5));
// accelerate and print true for current speed
robot.accelerate();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 10));
// brake and print true for current speed
robot.brake();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 5));
// accelerate and print true for current speed
robot.accelerate();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 10));
// accelerate and print true for current speed
robot.accelerate();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 15));
// accelerate and print true for current speed
robot.accelerate();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 20));
// accelerate and print true for current speed
robot.accelerate();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 20));
// break and print true for current speed
robot.brake();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 15));
// brake and print true for current speed
robot.brake();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 10));
// brake and print true for current speed
robot.brake();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 5));
// brake and print true for current speed
robot.brake();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 0));
// brake and print true for current speed
robot.brake();
System.out.println(doubleEquals(robot.getCurrentSpeed(), 0));
// print current status
robot.printStatus();
}
public static void main(String[] args) {
testAutoRobot();
}
/**
* Compare double value.
*
* @param a double value.
* @param b double value.
* @return true if a and b are equal.
*/
public static boolean doubleEquals(double a, double b) {
return Math.abs(a - b) < 0.00001;
}
}

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lab/lab2/Question1/SumAndAverage.java Normal file
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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022-03-02
* Assignment: #1 Question 1
* Description: This program is used to calculate the sum and average of the numbers.
* Input: The numbers
* Output: The sum and average of the numbers
* Version: 1.0
*/
public class SumAndAverage {
public static void main(String[] args) {
int sum = 0; // Store the accumulated sum init to 0
double average; // average in double
int lowerbound = 1; // The lowerbound to sum
int upperbound = 100; // The upperbound to sum
// Use a for-loop to sum from lowerbound to upperbound
for (int number = lowerbound; number <= upperbound; number++) {
// add only odds number
if (number % 2 != 0) {
sum += number;
}
}
// Compute average in double. Beware that int/int produces int.
average = (double) sum / (upperbound - lowerbound + 1);
// Print sum and average
System.out.println("The sum is " + sum);
System.out.println("The average is " + average);
// 6.1 while loop
System.out.println("---- While-loop:");
sum = 0;
int number = lowerbound;
while (number <= upperbound) {
// only add number that is divisible by 7
if (number % 7 == 0) {
sum += number;
}
number++;
}
// Compute average in double. Beware that int/int produces int.
average = (double) sum / (upperbound - lowerbound + 1);
// Print sum and average
System.out.println("The sum is " + sum);
System.out.println("The average is " + average);
// 6.2 do-while
System.out.println("---- Do-while:");
sum = 0; // Reset sum
number = lowerbound;
do {
// sum of squares of number
sum += number * number;
number++;
} while (number <= upperbound);
// Compute average in double. Beware that int/int produces int.
average = (double) sum / (upperbound - lowerbound + 1);
// Print sum and average
System.out.println("The sum is " + sum);
System.out.println("The average is " + average);
}
}

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lab/lab2/Question2/TimeTable.java Normal file
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/*
* Authro: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022-03-02
* Description: A table of multiplication table of 1 to 9.
* Using nested for loop to print the table.
* Assignemnt: #2 Question2
* Output:
* | 1 2 3 4 5 6 7 8 9
---------------------------------------
1 | 1 2 3 4 5 6 7 8 9
2 | 2 4 6 8 10 12 14 16 18
3 | 3 6 9 12 15 18 21 24 27
4 | 4 8 12 16 20 24 28 32 36
5 | 5 10 15 20 25 30 35 40 45
6 | 6 12 18 24 30 36 42 48 54
7 | 7 14 21 28 35 42 49 56 63
8 | 8 16 24 32 40 48 56 64 72
9 | 9 18 27 36 45 54 63 72 81
*/
public class TimeTable {
public static void printHeader() {
System.out.println("* | 1 2 3 4 5 6 7 8 9");
System.out.println("---------------------------------------");
}
public static void printLineBegin(int i) {
System.out.print(i + " |");
}
public static int spaceBefore(int i) {
// format the number to be printed
String s = Integer.toString(i);
// calculate the number of spaces before the number
int len = s.length();
// return the number of spaces
int space = 4 - len;
return space;
}
public static void main(String[] args) {
// print the two lines header
printHeader();
// loop for main content
for (int i = 1; i <= 9; i++) {
printLineBegin(i);
// loop for each number in the line
for (int j = 1; j <= 9; j++) {
int number = i * j;
// print the space before the number
for (int k = 0; k < spaceBefore(number); k++) {
System.out.print(" ");
}
// print the number
System.out.print(number);
}
// print the end of the line
System.out.println();
}
}
}

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lab/lab2/Question3/TestPalindrome.java Normal file
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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022-03-02
* Description: Test whether a sentence is a palindrome, iguore the case punctuation and spaces.
* Assignment: #2 Question 3
*/
import java.util.Scanner;
public class TestPalindrome {
public static void main(String[] args) {
System.out.print("Enter a String: ");
Scanner in = new Scanner(System.in);
// read a line of input from the user
String inStr = in.nextLine();
// close the scanner object
in.close();
// convert the string to lower case
String str = inStr.toLowerCase();
// remove all the punctuation using Character.isLetter()
// str = str.replaceAll("[^a-zA-Z0-9]", "");
String str2 = str;
str = "";
for (int i = 0; i < str2.length(); i++) {
if (Character.isLetter(str2.charAt(i))) {
str += str2.charAt(i);
}
}
// reverse the string
String reverse = new StringBuffer(str).reverse().toString();
// compare the two strings
// if they are the same, the string is a palindrome
// otherwise, it is not
System.out.format("\"%s\" is %s a palindrome.\n", inStr,
str.equals(reverse) ? "" : "not ");
}
}

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lab/lab3/Question1/Start.java Normal file
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public class Start {
public static void main(String[] args) {
Student.testStudent();
}
}

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lab/lab3/Question1/Student.java Normal file
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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022/03/03
* Description: Student class
*/
public class Student {
/**
* Student's ID number
*/
private int ID;
/**
* Constructor A public constructor with one parameter
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*/
public Student(int ID) {
this.ID = ID;
}
/**
* Getter A public getter for the ID.
*
* @return the ID of the student
*/
public int getID() {
return ID;
}
/**
* Test method A public method to test the class
*
* @return void
*/
public static void testStudent() {
Student s1 = new Student(-39);
Student s2 = new Student(114514);
Student s3 = new Student(0);
// print true
System.out.println(s1.getID() == -39);
System.out.println(s2.getID() == 114514);
System.out.println(s3.getID() == 0);
}
}

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lab/lab3/Question2/Start.java Normal file
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public class Start {
public static void main(String[] args) {
Student.testStudent();
}
}

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lab/lab3/Question2/Student.java Normal file
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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022/03/03
* Description: Student class
*/
public class Student {
/**
* Student's ID number
*/
private int ID;
/**
* Constructor A public constructor with one parameter
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*/
public Student(int ID) {
if (ID > 0) {
this.ID = ID;
} else {
this.ID = 0;
}
}
/**
* Getter A public getter for the ID.
*
* @return the ID of the student
*/
public int getID() {
return ID;
}
/**
* Test method A public method to test the class
*
* @return void
*/
public static void testStudent() {
Student s1 = new Student(-39);
Student s2 = new Student(114514);
Student s3 = new Student(0);
// print true
System.out.println(s1.getID() == 0);
System.out.println(s2.getID() == 114514);
System.out.println(s3.getID() == 0);
}
}

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lab/lab3/Question3/Start.java Normal file
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public class Start {
public static void main(String[] args) {
Student.testStudent();
}
}

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lab/lab3/Question3/Student.java Normal file
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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022/03/03
* Description: Student class
*/
public class Student {
/**
* Student's ID number
*/
private int ID;
/**
* Student's name
*/
private String name;
/**
* Constructor A public constructor with one parameter
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*
* @param name the name of the student.
*/
public Student(int ID, String name) {
// if the id is not positive, set it to 0
if (ID > 0) {
this.ID = ID;
} else {
this.ID = 0;
}
// set the name
this.name = name;
}
/**
* Getter A public getter for the ID.
*
* @return the ID of the student
*/
public int getID() {
return ID;
}
/**
* Getter A public getter for the name.
*
* @return the name of the student
*/
public String getName() {
return name;
}
/**
* Setter A public setter for the name.
*
* @param name the name of the student
*
* @return void
*/
public void setName(String name) {
this.name = name;
}
/**
* Test method A public method to test the class
*
* @return void
*/
public static void testStudent() {
// create students
Student s1 = new Student(-1, "Walter");
Student s2 = new Student(0, "Yongyuan");
Student s3 = new Student(1, "Chen");
// print true for id
System.out.println(s1.getID() == 0);
System.out.println(s2.getID() == 0);
System.out.println(s3.getID() == 1);
// print true for name
System.out.println(s1.getName().equals("Walter"));
System.out.println(s2.getName().equals("Yongyuan"));
System.out.println(s3.getName().equals("Chen"));
// change name
s1.setName("Walter Wang");
s2.setName("Yongyuan Wang");
s3.setName("Chen Wang");
// print true for name
System.out.println(s1.getName().equals("Walter Wang"));
System.out.println(s2.getName().equals("Yongyuan Wang"));
System.out.println(s3.getName().equals("Chen Wang"));
}
}

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lab/lab3/Question4/Start.java Normal file
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public class Start {
public static void main(String[] args) {
Student.testStudent();
}
}

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lab/lab3/Question4/Student.java Normal file
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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022/03/03
* Description: Student class
*/
public class Student {
/**
* Student's ID number
*/
private int ID;
/**
* Student's name
*/
private String name;
/**
* A single character representing the grade of the student
*/
private char grade;
/**
* Constructor A public constructor with one parameter
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*
* @param name the name of the student.
*/
public Student(int ID, String name) {
// if the id is not positive, set it to 0
if (ID > 0) {
this.ID = ID;
} else {
this.ID = 0;
}
// set the name
this.name = name;
// set the grade to default 'A'
this.grade = 'A';
}
/**
* Getter A public getter for the ID.
*
* @return the ID of the student
*/
public int getID() {
return ID;
}
/**
* Getter A public getter for the name.
*
* @return the name of the student
*/
public String getName() {
return name;
}
/**
* Setter A public setter for the name.
*
* @param name the name of the student
*
* @return void
*/
public void setName(String name) {
this.name = name;
}
/**
* Getter A public getter for the grade.
*
* @return the grade of the student
*/
public char getGrade() {
return grade;
}
/**
* Setter A public setter for the grade.
*
* @param grade the grade of the student
*
* @return void
*/
public void setGrade(char grade) {
this.grade = grade;
}
/**
* Test method A public method to test the class
*
* @return void
*/
public static void testStudent() {
// create students
Student s1 = new Student(-1, "Walter");
Student s2 = new Student(0, "Yongyuan");
Student s3 = new Student(1, "Chen");
// print true for id
System.out.println(s1.getID() == 0);
System.out.println(s2.getID() == 0);
System.out.println(s3.getID() == 1);
// print true for name
System.out.println(s1.getName().equals("Walter"));
System.out.println(s2.getName().equals("Yongyuan"));
System.out.println(s3.getName().equals("Chen"));
// change the name
s1.setName("Walter Wang");
s2.setName("Yongyuan Wang");
s3.setName("Chen Wang");
// print true for name
System.out.println(s1.getName().equals("Walter Wang"));
System.out.println(s2.getName().equals("Yongyuan Wang"));
System.out.println(s3.getName().equals("Chen Wang"));
// check default grade
System.out.println(s1.getGrade() == 'A');
System.out.println(s2.getGrade() == 'A');
System.out.println(s3.getGrade() == 'A');
// set grade
s1.setGrade('B');
s2.setGrade('C');
s3.setGrade('D');
// check grade
System.out.println(s1.getGrade() == 'B');
System.out.println(s2.getGrade() == 'C');
System.out.println(s3.getGrade() == 'D');
}
}

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lab/lab3/Question5/Start.java Normal file
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public class Start {
public static void main(String[] args) {
Student.testStudent();
}
}

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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022/03/03
* Description: Student class
*/
public class Student {
/**
* Student's ID number
*/
private int ID;
/**
* Student's name
*/
private String name;
/**
* A single character representing the grade of the student
*/
private char grade;
/**
* Constructor A public constructor with one parameter
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*
* @param name the name of the student.
*/
public Student(int ID, String name) {
this(ID, name, 'A');
}
/**
* Constructor A public constructor with three parameters
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*
* @param name the name of the student.
*
* @param grade the grade of the student, if the grade is not one of these, it
* will be set to 'A'
*/
public Student(int ID, String name, char grade) {
// if the id is not positive, set it to 0
if (ID > 0) {
this.ID = ID;
} else {
this.ID = 0;
}
// set the name
this.name = name;
// set the grade
this.grade = grade;
}
/**
* Getter A public getter for the ID.
*
* @return the ID of the student
*/
public int getID() {
return ID;
}
/**
* Getter A public getter for the name.
*
* @return the name of the student
*/
public String getName() {
return name;
}
/**
* Setter A public setter for the name.
*
* @param name the name of the student
*
* @return void
*/
public void setName(String name) {
this.name = name;
}
/**
* Getter A public getter for the grade.
*
* @return the grade of the student
*/
public char getGrade() {
return grade;
}
/**
* Setter A public setter for the grade.
*
* @param grade the grade of the student
*
* @return void
*/
public void setGrade(char grade) {
this.grade = grade;
}
/**
* Test method A public method to test the class
*
* @return void
*/
public static void testStudent() {
// create students
Student s1 = new Student(-1, "Walter");
Student s2 = new Student(0, "Yongyuan");
Student s3 = new Student(1, "Chen");
// print true for id
System.out.println(s1.getID() == 0);
System.out.println(s2.getID() == 0);
System.out.println(s3.getID() == 1);
// print true for name
System.out.println(s1.getName().equals("Walter"));
System.out.println(s2.getName().equals("Yongyuan"));
System.out.println(s3.getName().equals("Chen"));
// change the name
s1.setName("Walter Wang");
s2.setName("Yongyuan Wang");
s3.setName("Chen Wang");
// print true for name
System.out.println(s1.getName().equals("Walter Wang"));
System.out.println(s2.getName().equals("Yongyuan Wang"));
System.out.println(s3.getName().equals("Chen Wang"));
// check default grade
System.out.println(s1.getGrade() == 'A');
System.out.println(s2.getGrade() == 'A');
System.out.println(s3.getGrade() == 'A');
// set grade
s1.setGrade('B');
s2.setGrade('C');
s3.setGrade('D');
// check grade
System.out.println(s1.getGrade() == 'B');
System.out.println(s2.getGrade() == 'C');
System.out.println(s3.getGrade() == 'D');
// create students with grade different from A
Student s4 = new Student(2, "Chen", 'B');
Student s5 = new Student(3, "Yongyuan", 'C');
Student s6 = new Student(4, "Walter", 'D');
// print true for grade
System.out.println(s4.getGrade() == 'B');
System.out.println(s5.getGrade() == 'C');
System.out.println(s6.getGrade() == 'D');
}
}

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public class Start {
public static void main(String[] args) {
Student.testStudent();
}
}

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lab/lab3/Question6/Student.java Normal file
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/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022/03/03
* Description: Student class
*/
/**
* This class is used to store student information
*/
public class Student {
/**
* Student's ID number
*/
private int ID;
/**
* Student's name
*/
private String name;
/**
* A single character representing the grade of the student
*/
private char grade;
/**
* Whether the student is sleeping in the lab, default is false
*/
private boolean sleeping;
/**
* Constructor A public constructor with one parameter
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*
* @param name the name of the student.
*/
public Student(int ID, String name) {
this(ID, name, 'A');
}
/**
* Constructor A public constructor with three parameters
*
* @param id the ID of the student, only accept positive integer if the id is
* not positive, it will be set to 0
*
* @param name the name of the student.
*
* @param grade the grade of the student, if the grade is not one of these, it
* will be set to 'A'
*/
public Student(int ID, String name, char grade) {
// if the id is not positive, set it to 0
if (ID > 0) {
this.ID = ID;
} else {
this.ID = 0;
}
// set the name
this.name = name;
// set the grade
this.grade = grade;
// std is not sleeping by default
this.sleeping = false;
}
/**
* Getter A public getter for the ID.
*
* @return the ID of the student
*/
public int getID() {
return ID;
}
/**
* Getter A public getter for the name.
*
* @return the name of the student
*/
public String getName() {
return name;
}
/**
* Setter A public setter for the name.
*
* @param name the name of the student
*
* @return void
*/
public void setName(String name) {
this.name = name;
}
/**
* Getter A public getter for the grade.
*
* @return the grade of the student
*/
public char getGrade() {
return grade;
}
/**
* Setter A public setter for the grade.
*
* @param grade the grade of the student
*
* @return void
*/
public void setGrade(char grade) {
this.grade = grade;
}
/**
* Getter A public getter for the sleeping
*
* @return the sleeping of the student
*/
public boolean isSleeping() {
return sleeping;
}
/**
* Makes the student fall asleep. When a student fall asleep, the grade of the
* student decraeses by one letter grade. Any other grade will be set to 'F'.
*
* @return void
*/
public void goToSleep() {
sleeping = true;
// set student grade decrase by one letter,
// if the grade is not one of these, set it to 'F'
if (this.grade >= 'A' && this.grade < 'F') {
this.grade++;
} else {
this.grade = 'F';
}
}
/**
* Wake up the student. When a student wakes up, the grade of the student
* does not go up.
*
* @return void
*/
public void wakeUp() {
sleeping = false;
}
/**
* Test method A public method to test the class
*
* @return void
*/
public static void testStudent() {
// create students
Student s1 = new Student(-1, "Walter");
Student s2 = new Student(0, "Yongyuan");
Student s3 = new Student(1, "Chen");
// print true for id
System.out.println(s1.getID() == 0);
System.out.println(s2.getID() == 0);
System.out.println(s3.getID() == 1);
// print true for name
System.out.println(s1.getName().equals("Walter"));
System.out.println(s2.getName().equals("Yongyuan"));
System.out.println(s3.getName().equals("Chen"));
// change the name
s1.setName("Walter Wang");
s2.setName("Yongyuan Wang");
s3.setName("Chen Wang");
// print true for name
System.out.println(s1.getName().equals("Walter Wang"));
System.out.println(s2.getName().equals("Yongyuan Wang"));
System.out.println(s3.getName().equals("Chen Wang"));
// check default grade
System.out.println(s1.getGrade() == 'A');
System.out.println(s2.getGrade() == 'A');
System.out.println(s3.getGrade() == 'A');
// set grade
s1.setGrade('B');
s2.setGrade('C');
s3.setGrade('D');
// check grade
System.out.println(s1.getGrade() == 'B');
System.out.println(s2.getGrade() == 'C');
System.out.println(s3.getGrade() == 'D');
// create students with grade different from A
Student s4 = new Student(2, "Chen", 'B');
Student s5 = new Student(3, "Yongyuan", 'C');
Student s6 = new Student(4, "Walter", 'D');
// print true for grade
System.out.println(s4.getGrade() == 'B');
System.out.println(s5.getGrade() == 'C');
System.out.println(s6.getGrade() == 'D');
// check default sleeping status
System.out.println(s4.isSleeping() == false);
System.out.println(s5.isSleeping() == false);
System.out.println(s6.isSleeping() == false);
// make students fall asleep
s4.goToSleep();
s5.goToSleep();
s6.goToSleep();
// check sleeping status after fall asleep
System.out.println(s4.isSleeping() == true);
System.out.println(s5.isSleeping() == true);
System.out.println(s6.isSleeping() == true);
// check grade after fall asleep
System.out.println(s4.getGrade() == 'C');
System.out.println(s5.getGrade() == 'D');
System.out.println(s6.getGrade() == 'E');
// student s6 sleep several times
s6.goToSleep();
s6.goToSleep();
s6.goToSleep();
s6.goToSleep();
// check grade after sleep several times
System.out.println(s6.getGrade() == 'F');
}
}