@Override
    public String toString() {
        return "KeyQueryMetadata {" +
                "activeHost=" + activeHost +
                ", standbyHosts=" + standbyHosts +
                ", partition=" + partition +
                '}';
    }
Get the store partition corresponding to the key.

@return store partition number
streams/src/main/java/org/apache/kafka/streams/KeyQueryMetadata.java