Java Collection How to - Get an Element from a List, get a sublist








Question

We would like to know how to get an Element from a List, get a sublist.

Answer

The ArrayList class supports retrieval of a single element by index with 'public Object get(int index)'.

import java.util.ArrayList;
import java.util.List;
//from  www .  j a v  a  2  s. c  o m
public class MainClass {
  public static void main(String args[]) throws Exception {

    List list = new ArrayList();
    list.add("A");
    list.add("B");
    list.add("C");

    System.out.println(list.get(2));

  }
}

The code above generates the following result.

Get Sub List of ArrayList

import java.util.ArrayList;
import java.util.List;
/*from  ww w.j av a2  s  .  c  o  m*/
public class Main {
  public static void main(String[] args) {
    ArrayList<String> arrayList = new ArrayList<String>();

    arrayList.add("1");
    arrayList.add("2");
    arrayList.add("3");
    arrayList.add("4");
    arrayList.add("5");

    List lst = arrayList.subList(1, 3);
    for (int i = 0; i < lst.size(); i++)
      System.out.println(lst.get(i));

    // remove one element from sub list
    Object obj = lst.remove(0);
    System.out.println(obj + " is removed");

    for (String str: arrayList)
      System.out.println(str);
  }
}