@Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + (this.endpoint == null ? 0 : this.endpoint.hashCode());
        result = prime * result + this.idx;
        return result;
    }
To judge whether the priority election function is disabled or not in this node.

@return the result that whether this node has priority election function or not.
jraft-core/src/main/java/com/alipay/sofa/jraft/entity/PeerId.java