Java Unicode to TextArea -

ok, have tried hard coding unicode program, conditional statement won't read √- matched in textarea. i'm writing calculator program , want java read nan. skips on else if statement when i'm using textarea itself. tested without textarea , nan, returns number used in textarea.

for example:

test program (without gui) --> runs fine outputs nan

string text = "√-25"; system.out.println(text); arraylist<string> op = new arraylist(); arraylist<float> num = new arraylist(); scanner opscan = new scanner(text).usedelimiter("[[.][0-9]]+"); scanner numscan = new scanner(text).usedelimiter("[-+*/√]+"); int iop = 0; int inum = 0; float root = 0; while (opscan.hasnext()) {     op.add(opscan.next()); } opscan.close(); system.out.println(op + "op size: " + op.size());  while (numscan.hasnextfloat()) {     if (op.get(iop).equals("-")) {         num.add(-numscan.nextfloat());         op.set(iop, "+");     } else if (op.get(iop).equals("--")) {         num.add(-numscan.nextfloat());         op.set(iop, "-");     } else if (op.get(iop).equals("+-")) {         num.add(-numscan.nextfloat());         op.set(iop, "+");     } else if (op.get(iop).equals("*-")) {         num.add(-numscan.nextfloat());         op.set(iop, "*");     } else if (op.get(iop).equals("/-")) {         num.add(-numscan.nextfloat());         op.set(iop, "/");     } else if (op.get(iop).equals("√-")) {         num.add(-numscan.nextfloat());         op.set(iop, "√");     } else {         num.add(numscan.nextfloat());     }     iop++; } system.out.println(num + "num size: " + num.size()); system.out.println(op + "num size: " + num.size());  while (op.contains("√")) {     try {         if (op.get(iop).equals("√")) {             root = (float) math.sqrt(num.get(inum));             num.set(inum, root);             op.remove(iop);              system.out.println(root + " root!");         }          if (op.get(0).matches("[+-*/]+")) {             iop++;             inum++;         }     } catch (indexoutofboundsexception indexoutofboundsexception) {         system.out.println("index error bypassed! " + "index: " + "iop:" + iop + " inum:" + inum + " | size: " + "iop:" + op.size() + " inum:" + num.size());         iop = 0;         inum = 0;     } } 

program gui & textarea outputs --> 25

use unicode representation of √

\u221a 

e.g.

public static void main(string[] args) {         system.out.println("encoding: " + system.getproperty("file.encoding"));         jtextarea area = new jtextarea(10, 30);         jscrollpane pane = new jscrollpane(area);         joptionpane.showmessagedialog(null, pane);         string text = area.gettext();         char sqrt = '\u221a';         if (text.contains(character.tostring (sqrt))) {             system.out.println("yes " + text);         } else {             system.out.println("no " + text);         }     }