import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;


/**
 * httpclient 后台请求http工具类
 * @author zhaosongbin
 * @date 2019/4/2 14:17
 */
public class HttpClientUtil {

    private final static Logger logger = LoggerFactory.getLogger(HttpClientUtil.class);


    /**
     * get请求
     *
     * @param url
     * @param token
     * @return
     */
    public static String get(String url, String token) {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        HttpGet httpGet = new HttpGet(url);
        try {
            if (token != null && !"".equals(token)) {
                httpGet.addHeader("Authorization", "Bearer " + token);
            } else {
                logger.warn("http--get方法--token为空");
            }
            HttpResponse response = httpClient.execute(httpGet);

            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "UTF-8");
            return result;

        } catch (ClientProtocolException e) {
            logger.error("http--get方法--ClientProtocolException异常");
            e.printStackTrace();
        } catch (IOException e) {
            logger.error("http--get方法--IOException异常");
            e.printStackTrace();
        }

        logger.error("http--get方法--失败");
        return null;
    }


    /**
     * post请求
     *
     * @param url
     * @param param
     * @param type
     * @param token
     * @return java.lang.String
     * @author zhaosongbin
     * @date 2019/4/3
     */
    public static String post(String url, String param, String type, String token) {

        try {
            CloseableHttpClient httpClient = HttpClients.createDefault();
            HttpPost httpPost = new HttpPost(url);

            if (token != null && !"".equals(token)) {
                httpPost.addHeader("Authorization", "Bearer " + token);
            } else {
                logger.warn("http--post方法--token为空");
            }
            if (param != null && !"".equals(param)) {
                httpPost.addHeader("Content-Type", type);
                contentType(param, type, httpPost);
            } else {
                logger.warn("http--post方法--param为空");
            }
            
            CloseableHttpResponse response = httpClient.execute(httpPost);
            HttpEntity entity = response.getEntity();
            String responseContent = EntityUtils.toString(entity, "UTF-8");

            response.close();
            httpClient.close();
            return responseContent;

        } catch (ClientProtocolException e) {
            logger.error("http--post方法--ClientProtocolException异常");
            e.printStackTrace();
        } catch (IOException e) {
            logger.error("http--post方法--IOException异常");
            e.printStackTrace();
        }

        logger.error("http--post方法--失败");
        return null;
    }


    /**
     * 判断参数类型,传参模式
     *
     * @param param
     * @param type
     * @param httpPost
     * @return void
     * @author zhaosongbin
     * @date 2019/4/3
     */
    private static void contentType(String param, String type, HttpPost httpPost) {

        try {

            if (type.equals(ContentType.json)) {
                httpPost.setEntity(new StringEntity(param));
            } else if (type.equals(ContentType.x_www_form_urlencoded)) {
                httpPost.setEntity(new ByteArrayEntity(param.getBytes()));
            }

        } catch (Exception e) {
            logger.error("ContentType 判断方法异常");
            e.printStackTrace();
        }

    }

}

参数转换

json 格式请求

 /**
     * 将java对象转换为json格式字符串
     * @param obj
     * @return json string
     */
    public static String objToJson(Object obj) {
        ObjectMapper om = new ObjectMapper();
        try {
            String json = om.writeValueAsString(obj);
            return json;
        } catch (JsonProcessingException e) {
            e.printStackTrace();
        }
        return null;
    }

//string 转json数组
String name = "张三";
String age = "18";
String sex = "男";

String json = "{\"name\":\"" + name + "\"," +
              "\"age \":\"" + age + "\"," +
              "\"sex \":\"" + sex + "\",}";

/**
 * @author zhaosongbin
 * @date 2019/4/19
 */
public class User {

    private String name;
    private String age;
    private String sex;


    @Override
    public String toString() {
        return "name=" + name + "&" +
                "age=" + age + "&" +
                "sex=" + sex + "&";
    }

    //get  set  略....
}