dap4/d4core/src/main/java/dap4/core/util/DapUtil.java
static public String
    nullify(String path)
    {
        return (path != null && path.length() == 0 ? null : path);
    }
static public String
    nullify(String path)
    {
        return (path != null && path.length() == 0 ? null : path);
    }
static public String nullify ( String path ) { return ( path != null && path . length ( ) == 0 ? null : path ) ; }
Convert "" paths to null

@param path
@return path or null
Convert paths to null