Create type specific collections : Map « Collections Data Structure « Java






  1. Java
  2. Collections Data Structure
  3. Map

Create type specific collections

         
import java.util.Map;
import java.util.HashMap;
import java.util.List;
import java.util.ArrayList;

public class Main {
  public static void main(String[] args) {
    Map<Integer, String> grades = new HashMap<Integer, String>();

    grades.put(1, "A");
    grades.put(2, "B");
    grades.put(3, "C");
    grades.put(4, "D");
    grades.put(5, "E");

    String value = grades.get(1);

    List<String> dayNames = new ArrayList<String>();
    dayNames.add("Sunday");
    dayNames.add("Monday");
    dayNames.add("Tuesday");
    dayNames.add("Wednesday");

    String firstDay = dayNames.get(0);
  }
}








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