public class MyData implements Parcelable {
    private String firstName;
    private String lastName;

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel destination, int flags) {
        destination.writeString(firstName);
        destination.writeString(lastName);
    }
}

public static final Creator<MyData> CREATOR = new Creator<MyData>() {
    @Override public MyData createFromParcel(Parcel source) { return new MyData(source); }
    @Override public MyData[] newArray(int size) { return new MyData[size]; }
};

private MyData(Parcel source) {
    firstName = source.readString();
    lastName = source.readString();
}

public class MyData implements Parcelable {
    private String name;
    private int age;

    @Override
    public void writeToParcel(Parcel destination, int flags) {
        destination.writeString(name);
        destination.writeInt(age);
    }

    private MyData(Parcel source) {
        age = source.readInt();
        name = source.readString();
    }
    ...
}