Assert error!! how to solve that problem?

Question

Hi,
when i use an assert after the compilation , the error is:
C:\CLASSES>javac Assertion.java
Assertion.java:11: as of release 1.4, 'assert' is a keyword, and may not be used as an identifier
(try -source 1.3 or lower to use 'assert' as an identifier)
public static void assert(boolean expression, String why) {
^
1 error
The tutorial says: In order for Code Sample 1(Doesn't matter) to compile, use -source 1.3 because assert is a keyword as of J2SE 1.4.
what is the source 1.3 ?? where and what the hell is that?? LOL =))
thanks!

Answer 1

i understand and i don't understand.
lol
thats possible for someone who is using xemacs but someone who is using Eclipse or JCreator how do i do that?
if u don't want to answer that question could u put an assertion in this code, for example : asser -> if the num < = 0 !
here is the code:
import java.io.*;
public class Capicua {
     public static void main (String[] args) throws Exception {
          int digit, num;
          int inverted = 0;
          int x;     
               BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
               System.out.print(" Insert number: ");
               num=Integer.parseInt(br.readLine().trim());
               Assertion.assert(num <= 0, "Number can't be shorter or equals to zero!"); <--- how do i put an assert here? ( with the "do - while" its easy, but and with the asserts?
               x=num;
               while(num > 0) {
               digit = num % 10;
               num = num /10;
               inverted = inverted * 10 + digit;
               System.out.println("inverted = " + inverted);
                    if(inverted == x) {
                         System.out.println("Capicua");
                    }else{
                         System.out.println("not a capicau");
}