A map declared to hold objects of a type T can also hold objects that extend from T : Map « Collections Data Structure « Java






  1. Java
  2. Collections Data Structure
  3. Map

A map declared to hold objects of a type T can also hold objects that extend from T

         
import java.util.HashMap;
import java.util.Map;

public class Main {
  public static void main(String[] argv) {

    Map<Number, String> numMap = new HashMap<Number, String>();

    numMap.put(.5, "half");
    numMap.put(1, "first");
  }
}








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