问题一

if (headers != null) {
            headers.entrySet().stream().forEach(
                    entry -> {
                        httpGet.setHeader(entry.getKey(), entry.getValue());
                    }
            );
        }

这段是什么意思？

问题二

EntityUtils.toString(httpResponse.getEntity(),"UTF-8");

这句是什么意思？

源码

import org.apache.http.util.EntityUtils;

public static String get(CloseableHttpClient httpClient, String url, Map<String, String> headers) throws ClientProtocolException, IOException {
        HttpGet httpGet = new HttpGet(url);
        if (headers != null) {
            headers.entrySet().stream().forEach(
                    entry -> {
                        httpGet.setHeader(entry.getKey(), entry.getValue());
                    }
            );
        }
        HttpResponse httpResponse = httpClient.execute(httpGet);
        int code = httpResponse.getStatusLine().getStatusCode();
        if (code >= 299) {
            log.error("status code is {}", code);
        }
        return EntityUtils.toString(httpResponse.getEntity(),"UTF-8");
    }