Java - Type mismatch: cannot convert from element type Object to String

Question

I\'m having this error:

Type mismatch: cannot convert from element type Object to String

This is the code in error:

Answer 1

I think you're casting is wrong..

What is u.getAllPermissions().get(k); should return? List of something? if it does so you need to add type of the generic list

List<String> perms = (List<String>)u.getAllPermissions().get(k);

If that doesn't work you can also try to do

for (Object o : perms) {
 String s = o.toString();
 .....
}

Hope that helps.. If not answer my question and it will be easier to help

Answer 2

try this :

public List<String> customPrefixes(PermissionUser u)
  {
    List<String> returnlist = new ArrayList<String>();
    for (String k : u.getAllPermissions().keySet()) {
      List<String> perms = (List<String>)(u.getAllPermissions()).get(k);
      for (String s : perms) {
        String[] split = s.split(".");
        if ((split.length >= 3) &&
          (split[0].equalsIgnoreCase("plugin")) &&
          (split[1].equalsIgnoreCase("prefix"))) {
          returnlist.add(split[2]);
        }
      }

    }

    return returnlist;
  }

You were missing "<String>" in the List declaration