Collection: toArray() Returns an array containing the elements in this collection : Collection « Utility Classes « SCJP

1. SCJP
2. Utility Classes
3. Collection

import java.util.ArrayList;
import java.util.Collection;

public class MainClass {
  public static void main(String[] argv) {
    Collection c = new ArrayList();
    c.add("1");
    c.add("2");
    c.add("3");

    System.out.println(c.toArray().length);

  }
}

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