Simple code to page through Solr results with httpclient and jackson

SolrPager.java

import java.net.URI;

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

public class SolrPager {

	private final String solrEndpoint;

	public SolrPager(String solrEndpoint) {
		this.solrEndpoint = solrEndpoint;
	}

	void page() throws Exception {
		int rows = 1000;

		CloseableHttpClient httpclient = null;
		try {
			httpclient = HttpClients.createDefault();
			int start = 0;
			while (true) {
				HttpGet httpget = new HttpGet(buildParams(start, rows));
				CloseableHttpResponse response = httpclient.execute(httpget);
				try {
					HttpEntity entity = response.getEntity();
					if (entity == null) {
						break;
					}
					ObjectMapper mapper = new ObjectMapper();
					JsonNode tree = mapper.readTree(entity.getContent());
					JsonNode responseNode = tree.get("response");

					int nbdocs = 0;
					for (JsonNode doc : responseNode.get("docs")) {
						nbdocs++;
						// ... do something with doc...
					}

					if (nbdocs < rows) {
						break;
					}
					start += rows;

				} finally {
					response.close();
				}
			}

		} finally {
			if (httpclient != null) {
				httpclient.close();
			}
		}
	}

	private URI buildParams(int start, int rows) throws Exception {
		return new URIBuilder(new URI(solrEndpoint))
		.setPath("/solr/select")
		.setParameter("q", "*:*")
		.setParameter("fl", "id,title")
		.setParameter("wt", "json")
		.setParameter("start", String.valueOf(start))
		.setParameter("rows", String.valueOf(rows))
		.build();
	}

	public static void main(String[] args) throws Exception {
		new SolrPager("http://localhost:8888").page();
	}
}