package g_news; import java.util.regex.Matcher; import java.util.regex.Pattern; public class WelcomeToGnews{ private static final int ERR_RESULT = -1; private static final int NML_RESULT = 0; public static void main(String args[]) { // Argument check if (args.length != 1) { System.out.println("ERROR:Please enter one argument"); System.exit(ERR_RESULT); } // Type check Pattern p = Pattern.compile("[0-9]+"); Matcher m = p.matcher(args[0]); if (!m.find()) { System.out.println("ERROR:Please enter an integer."); System.exit(ERR_RESULT); } Integer i = Integer.valueOf(args[0]); // InputData check if(i >= 0) { System.out.println("INFO:The value entered is a positive number"); } else { System.out.println("INFO:The value entered is a negative number."); } System.exit(NML_RESULT); } }