jodd-core/src/main/java/jodd/util/ClassUtil.java
public static String getBeanPropertySetterName(final Method method) {
		int prefixLength = getBeanPropertySetterPrefixLength(method);
		if (prefixLength == 0) {
			return null;
		}
		String methodName = method.getName().substring(prefixLength);
		return StringUtil.decapitalize(methodName);
	}
public static String getBeanPropertySetterName(final Method method) {
		int prefixLength = getBeanPropertySetterPrefixLength(method);
		if (prefixLength == 0) {
			return null;
		}
		String methodName = method.getName().substring(prefixLength);
		return StringUtil.decapitalize(methodName);
	}
Returns beans property setter name or <code>null</code> if method is not a real setter.