Java – How Can I Write My ArrayList to a file, and Read (load) that file to the original ArrayList?

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You should use Java’s built in serialization mechanism.
To use it, you need to do the following:

  1. Declare the Club class as implementing Serializable:

    public class Club implements Serializable {
    ...
}

    This tells the JVM that the class can be serialized to a stream. You don’t have to implement any method, since this is a marker interface.

  2. To write your list to a file do the following:

    FileOutputStream fos = new FileOutputStream("t.tmp");
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(clubs);
oos.close();

  3. To read the list from a file, do the following:

    FileInputStream fis = new FileInputStream("t.tmp");
ObjectInputStream ois = new ObjectInputStream(fis);
List<Club> clubs = (List<Club>) ois.readObject();
ois.close();

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