ArrayList implements the empty Serializable interface : ArrayList « Collections « Java Tutorial

1. Java Tutorial
2. Collections
3. ArrayList

If all of the elements of an ArrayList are Serializable, you can then serialize the list to an ObjectOutputStream and later read it back from an ObjectInputStream.

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

import java.util.Arrays;
import java.util.List;

public class MainClass {

  public static void main(String[] a) throws Exception {

    List list = Arrays.asList(new String[] { "A", "B", "C", "D" });

    FileOutputStream fos = new FileOutputStream("list.ser");
    ObjectOutputStream oos = new ObjectOutputStream(fos);
    oos.writeObject(list);
    oos.close();

    FileInputStream fis = new FileInputStream("list.ser");
    ObjectInputStream ois = new ObjectInputStream(fis);
    List anotherList = (List) ois.readObject();
    ois.close();

    System.out.println(anotherList);
  }
}

[A, B, C, D]