Java Program to insert all elements of other Collection

import java.util.ArrayList;
import java.util.Vector;
public class Demo {
	public static void main(String[] args) {
		ArrayList<String>arr = new ArrayList<String>();
		arr.add("50");
		arr.add("100");
		arr.add("150");
		arr.add("200");
		arr.add("250");
		arr.add("300");
		Vector<String>vector = new Vector<String>();
		vector.add("500");
		vector.add("700");
		vector.add("800");
		vector.add("1000");
		// gets added at index 3
		arr.addAll(3, vector);
		System.out.println("Result after append...");
		for (String str: arr)
		 System.out.println(str);
	}
}