public static boolean equals(final Object a, final Object b) {
        if (a == null || b == null) {
            return a == b;
        }

        return a.equals(b);
    }
Equivalent to Object.equals except that it handles nulls. If a and b are both null, true is
returned.
dss-appconn/appconns/dss-eventchecker-appconn/src/main/java/com/webank/wedatasphere/dss/appconn/eventchecker/utils/Utils.java