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

I believe this should work :

Arrays.asList(newList.substring(1, newList.length() - 1).replaceAll("\\s", "").split(","));

• Take the string, remove the first and last bracket.
• Remove each spaces.
• Split by comma as delimiter, collect as list.

Note that if really you have to do this for a project, then there is something wrong in your code design. However, if this is just for curiosity purpose then this solution would work.

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After testing

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

String newList = list.toString();                
List myList = Arrays.asList(newList.substring(1, newList.length() - 1).replaceAll("\\s", "").split(","));

System.out.println(myList);

would compile properly and print :

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

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Edit

As per your comments, if really you want your variable to be an ArrayList instance then you could pass the list to ArrayList constructor :

ArrayList myList = new ArrayList(Arrays.asList(newList.substring(1, newList.length() - 1).replaceAll("\\s", "").split(",")));

You can't cast directly as Arrays.asList use it own builtin java.util.Arrays$ArrayList class.