src/org/tiefaces/components/websheet/utility/WebSheetUtility.java
public static boolean isNumeric(final String str) {

		String s = str;
		if (s.startsWith("-")) {
			s = s.substring(1);
		}
		char c;
		int i;
		int sLen = s.length();
		ShouldContinueParameter sPara = new ShouldContinueParameter(false,
				false, 0);

		for (i = 0; i < sLen; i++) {
			c = s.charAt(i);
			if (c < '0' || c > '9') {
				if (!shouldContinue(c, sPara)) {
					return false;
				}
			} else {
				if (sPara.isCommaHit()) {
					sPara.setSinceLastComma(sPara.getSinceLastComma() + 1);
				}
			}
		}
		return true;
	}
public static boolean isNumeric(final String str) {

		String s = str;
		if (s.startsWith("-")) {
			s = s.substring(1);
		}
		char c;
		int i;
		int sLen = s.length();
		ShouldContinueParameter sPara = new ShouldContinueParameter(false,
				false, 0);

		for (i = 0; i < sLen; i++) {
			c = s.charAt(i);
			if (c < '0' || c > '9') {
				if (!shouldContinue(c, sPara)) {
					return false;
				}
			} else {
				if (sPara.isCommaHit()) {
					sPara.setSinceLastComma(sPara.getSinceLastComma() + 1);
				}
			}
		}
		return true;
	}
Checks if is numeric.

@param str
the str
@return true, if is numeric