JAVA PROGRAMMING: Create a class Section that contains the following information

Question

JAVA PROGRAMMING:

Create a class Section that contains the following information:

String department (e.g., "CSC")

int courseNumber (e.g., 151)

int sectonNumber (e.g., 4101)

String instructor (e.g., "Sophie")

String title (e.g., "Introduction to Java")

Use Section objects as the key for a HashMap in the attached Register class. Sophie, Sally and Jack should all be in the same section. Everyone else should be in different sections.

import java.util.ArrayList;
import java.util.HashMap;

public class Register {

public static void main(String[] args) {
  HashMap<Section, ArrayList<String>> roster = new HashMap<>();
  Section s1 = new Section("CSC", 151, 0001, "Sophie Charlotte", "Intro to Java");
  Section s2 = new Section("CSC", 151, 0001, "Sophie C", "Introduction to Java");
  Section s3 = new Section("CSC", 151, 0001, "S Charlotte", "Java Introduction");
  Section s4 = new Section("CSC", 151, 0002, "Sophie C", "Introduction to Java");
  Section s5 = new Section("DBA", 151, 0001, "Sophie Charlotte", "SQL 1");
  Section s6 = new Section("CSC", 251, 0001, "Sophie Charlotte", "Adv Java");
  
  registerAStudent(roster, s1, "sophie");
  registerAStudent(roster, s2, "sally");
  registerAStudent(roster, s3, "jack");
  registerAStudent(roster, s4, "lassie");
  registerAStudent(roster, s5, "freckles");
  registerAStudent(roster, s6, "zipper");
  
  System.out.println(roster);
}

public static void registerAStudent(HashMap<Section, ArrayList<String>> roll, Section s, String student) {
  ArrayList<String> victims = roll.get(s);
  if (victims == null) {
   victims = new ArrayList<>();
   victims.add(student);
  }
  else {
   victims.add(student);
  }
  roll.put(s, victims);
}

}

Explanation / Answer

import java.util.ArrayList;
import java.util.HashMap;

class Section
   {
       String dept, instructor, title;
       int course_num, section_num;

       Section(String dept, int course_num, int section_number, String instructor, String title)
           {
               this.dept = dept;
               this.course_num = course_num;
               this.section_num = section_num;
               this.instructor = instructor;
               this.title = title;
           }
   }

public class Register
   {
       public static void main(String[] args)
           {
               HashMap<Section, ArrayList<String>> roster = new HashMap<>();
               Section s1 = new Section("CSC", 151, 0001, "Sophie Charlotte", "Intro to Java");
               Section s2 = new Section("CSC", 151, 0001, "Sophie C", "Introduction to Java");
               Section s3 = new Section("CSC", 151, 0001, "S Charlotte", "Java Introduction");
               Section s4 = new Section("CSC", 151, 0002, "Sophie C", "Introduction to Java");
               Section s5 = new Section("DBA", 151, 0001, "Sophie Charlotte", "SQL 1");
               Section s6 = new Section("CSC", 251, 0001, "Sophie Charlotte", "Adv Java");
  
               registerAStudent(roster, s1, "sophie");
               registerAStudent(roster, s2, "sally");
               registerAStudent(roster, s3, "jack");
               registerAStudent(roster, s4, "lassie");
               registerAStudent(roster, s5, "freckles");
               registerAStudent(roster, s6, "zipper");
  
               System.out.println(roster);
           }

       public static void registerAStudent(HashMap<Section, ArrayList<String>> roll, Section s, String student)
           {
               ArrayList<String> victims = roll.get(s);
               if (victims == null)
                   {
                       victims = new ArrayList<>();
                       victims.add(student);
                   }
               else
                   {
                       victims.add(student);
                   }
               roll.put(s, victims);
           }

   }

Related Questions

Navigate

• Browse (All)
• Browse J
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.