How to convert an arrayList.toString() into an actual arraylist

Question

In my software, since there is no Array data type in SQLite, I saved my ArrayList as a String. Now I need to use my array

Answer 1

This is not possible to do without ambiguity. Consider:

ArrayList list = new ArrayList();
list.add("name1, name2");
list.add("name3, name4");
list.add("name5");
list.add("name6");

String newList = list.toString();
System.out.println(newList);

Result: [name1, name2, name3, name4, name5, name6]

In order to accurately recover the original elements in the general case, your string format must be smarter than ArrayList.toString(). Consider a pre-defined way of encoding lists of strings, perhaps a JSON array, which would result in something like this for my example:

["name1, name2", "name3, name4", "name5", "name6"]

JSON also defines how to handle strings with quotes via escaping and/or use of alternate string start/end characters ' and ":

["he said, 'hello'", 'she said, "goodbye"', 'I said, "it\'s raining"']

(I also agree with other commenters that your database design should be reconsidered, but wanted to provide a clear answer illustrating the issues with string encodings of lists.)