jodd-props/src/main/java/jodd/props/Props.java
public Double getDoubleValue(final String key) {
		final String value = getValue(key);
		if (value == null) {
			return null;
		}
		return Double.valueOf(value);
	}
public Double getDoubleValue(final String key) {
		final String value = getValue(key);
		if (value == null) {
			return null;
		}
		return Double.valueOf(value);
	}
Returns double value of given property or {@code null} if property not found.