圖片傳輸采用字節(jié)流
訪問接口：

@Slf4j
@Controller
@RequestMapping(value = "/test", produces = "application/json; charset = utf-8")
public class HttpClientTest {

    @Autowired
    private HttpServiceImp httpServiceImp;

    @ResponseBody
    @RequestMapping(value = "/http", method = RequestMethod.GET,  produces = MediaType.IMAGE_JPEG_VALUE)
    public byte[] queryEventCount(HttpServletResponse httpResponse) {
        try {
            return httpServiceImp.doGet("http://***");
        } catch (Exception e) {
            // TODO Auto-generated catch block
            log.warn("error: {}", e);
        }
        return null;
    }

}

具體實(shí)現(xiàn)：

public byte[] doGet(String url) throws Exception {
        // 聲明 http get 請求
        HttpGet httpGet = new HttpGet(url);

        // 裝載配置信息
        httpGet.setConfig(config);

        // 發(fā)起請求
        CloseableHttpResponse response = this.httpClient.execute(httpGet);

        // 判斷狀態(tài)碼是否為200
        if (response.getStatusLine().getStatusCode() == 200) {
            // 返回響應(yīng)體的內(nèi)容
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            response.getEntity().writeTo(baos);
            return baos.toByteArray();
//            return EntityUtils.toString(response.getEntity(), "UTF-8");
        }
        return null;
    }