public final PoolingHttpClientConnectionManagerBuilder setConnectionFactory(
            final HttpConnectionFactory<ManagedHttpClientConnection> connectionFactory) {
        this.connectionFactory = connectionFactory;
        return this;
    }
Sets {@link HttpConnectionFactory} instance.

@return this instance.
httpclient5/src/main/java/org/apache/hc/client5/http/impl/io/PoolingHttpClientConnectionManagerBuilder.java