jodd-core/src/main/java/jodd/chalk/Chalk.java
public String on(final String string) {
		if (!enabled) {
			return string;
		}

		final StringBuilder sb = new StringBuilder();

		if (prefix != null) {
			sb.append(prefix).append("m");
		}

		sb.append(string);

		if (suffix != null) {
			sb.append(suffix).append("m");
		}

		return sb.toString();
	}
public String on(final String string) {
		if (!enabled) {
			return string;
		}

		final StringBuilder sb = new StringBuilder();

		if (prefix != null) {
			sb.append(prefix).append("m");
		}

		sb.append(string);

		if (suffix != null) {
			sb.append(suffix).append("m");
		}

		return sb.toString();
	}
Returns chalked string.