@Override
    public boolean check(String requiredKey) {
        if (StringUtils.isEmpty(requiredKey)) {
            return false;
        }
        if (this.property.getProperty(requiredKey) != null) {
            logger.debug("Property '{}' found in [{}]", requiredKey, this.property.getClass().getSimpleName());
            return true;
        } else {
            logger.debug("Property '{}' not found in [{}]", requiredKey, this.property.getClass().getSimpleName());
            return false;
        }
    }
Checks if the specified value is in <tt>SimpleProperty</tt>.

@param requiredKey the values to check if they exist in <tt>SimpleProperty</tt>
@return <tt>true</tt> if the specified key is in <tt>SimpleProperty</tt>; 
        <tt>false</tt> if otherwise, or if <tt>null</tt> or empty key is provided
agent-module/bootstraps/bootstrap-core/src/main/java/com/navercorp/pinpoint/bootstrap/resolver/condition/SystemPropertyCondition.java