@Override
    public Object get(String key, Object defaultValue) {
        return System.getProperty(key, defaultValue == null ? null : String.valueOf(defaultValue));
    }
Gets value from system via {@link System#getProperty}
@param key key to retrieve
@param defaultValue value to default to if none found
@return value found or default if none
core/src/main/java/com/github/dozermapper/core/config/resolvers/SystemPropertySettingsResolver.java