Question

How to write, in Java, a note-taking application which allows people to record notes and search for given notes by keyword - a public class Note (with instance variables subject and content) and a separate class Journal which will maintain a list of Note objects together with the name of the person owning the journal. Tons of thanks.

Answer 1

//NotesTaking.java

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
import java.util.stream.Collector;
import java.util.stream.Collectors;

public class NotesTaking {

   public static void main(String[] args) {
       //Scanners to get user inputs
       Scanner in1 = new Scanner(System.in);
       Scanner in2 = new Scanner(System.in);
       Scanner in3 = new Scanner(System.in);
       Scanner in4 = new Scanner(System.in);
       Scanner in5 = new Scanner(System.in);
      
       //variables to store the values from Scanners
       int choice;
       String subject;
       String content;
       String jounalName;
       String search;
      
       //List to store Notes List
       List<Note> noteList = new ArrayList<Note>();

       System.out.println("Enter number of notes to record : ");
       choice = in1.nextInt(); //number of notes to record
      
       //loop over number of notes to record
       while (choice-- > 0) {
           System.out.println("Enter subject name for notes : ");
           //enter subject for notes
           subject = in2.nextLine();
           System.out.println("Enter content for notes : ");
           //enter content for notes
           content = in3.nextLine();
           //create note object
           Note note = new Note(subject, content);
           //add note to noteList
           noteList.add(note);
       }
      
       System.out.println("Enter Journal name : ");
       //enter journal name
       jounalName = in4.nextLine();
       //create journal object
       Journal journal = new Journal(jounalName, noteList);

       System.out.println("Enter Search keyword : ");
       //enter search keyword
       search = in5.nextLine();
       //filter over the journal noteList that contains the search keyword
       List<Note> searchList = journal.getNoteList().stream().filter(note -> note.getSubject().contains(search) ||
               note.getContent().contains(search)).collect(Collectors.toList());
      
       //print note object
       for(Note note : searchList) {
           System.out.println("Subject : "+note.getSubject() + "\nContent : "+note.getContent() );
       }
      
       //close scanners
       in1.close();
       in2.close();
       in3.close();
       in4.close();
       in5.close();
   }

}

//Note.java

public class Note {

   private String subject;
   private String content;
  
   public Note(String subject, String content) {
       this.subject = subject;
       this.content = content;
   }

   public Note() {}

   public String getSubject() {
       return subject;
   }

   public void setSubject(String subject) {
       this.subject = subject;
   }

   public String getContent() {
       return content;
   }

   public void setContent(String content) {
       this.content = content;
   }
  
  
  
}

//Journal.java

import java.util.List;

public class Journal {

   private String name;
   private List<Note> noteList;  
  
   public Journal(String name, List<Note> noteList) {
       this.noteList = noteList;
       this.name = name;
   }

   public List<Note> getNoteList() {
       return noteList;
   }

   public void setNoteList(List<Note> noteList) {
       this.noteList = noteList;
   }

   public String getName() {
       return name;
   }

   public void setName(String name) {
       this.name = name;
   }
  
  
}