Create an array containing the keys in a map : Map « Collections Data Structure « Java






  1. Java
  2. Collections Data Structure
  3. Map

Create an array containing the keys in a map

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

public class Main {
  public static void main(String[] argv) throws Exception {
    Map map = new HashMap();

    Object[] objectArray = map.keySet().toArray();
    MyClass[] array = (MyClass[]) map.keySet().toArray(new MyClass[map.keySet().size()]);

  }
}

class MyClass {
}








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