实现发送post和get请求

需求背景

我们会有调用一个webservice项目的接口，此时需要用java来模拟post或者get请求来获取结果。
废话不多少，直接上代码。我们会在HttpClient的基础上再封装一个HttpClientUtil类，对外分别开放doGet和doPost方法，来实现get和post请求。

HttpClientUtil类代码

import java.io.IOException;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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

    /**
     * 使用Appache的HttpClient进行post请求
     * @param url http提交的url
     * @param map class:'Map', 并且value是可以通过String.valueOf(value) 转化为字符串的类型
     * 支持String,boolean,Integer等
     * @param charset 例如"utf-8"
     * @return 请求的结果，请求成功会返回json string
     */
  public static String doPost(String url, Map map, String charset) {
    HttpClient httpClient = null;
    HttpPost httpPost = null;
    String result = null;
    try {
      httpClient = HttpClients.createDefault();
      httpPost = new HttpPost(url);
      // 设置参数
      List list = new ArrayList();
      Iterator> iterator = map.entrySet().iterator();
      while (iterator.hasNext()) {
        Entry elem = (Entry) iterator.next();
        list.add(new BasicNameValuePair(elem.getKey(), String.valueOf(elem.getValue())));
      }
      if (list.size() > 0) {
        UrlEncodedFormEntity entity = new UrlEncodedFormEntity(list, charset);
        httpPost.setEntity(entity);
      }
      HttpResponse response = httpClient.execute(httpPost);
      if (response != null) {
        HttpEntity resEntity = response.getEntity();
        if (resEntity != null) {
          result = EntityUtils.toString(resEntity, charset);
        }
      }
    } catch (Exception ex) {
      ex.printStackTrace();
    }
    return result;
  }

  /**
   * 使用Appache的HttpClient进行get请求
   * @param url http提交的url
   * @param map must be null
   * @param charset 例如"utf-8"
   * @return 请求的结果，请求成功会返回json string
   */
    public static String doGet(String url, Map map,
            String charset) {
        map = null;
        HttpClient httpClient = null;
        HttpGet httpGet = null;
        String result = null;
        try {
            httpClient = HttpClients.createDefault();
            httpGet = new HttpGet(url);

            HttpResponse response = httpClient.execute(httpGet);
            if (response != null) {
                HttpEntity resEntity = response.getEntity();
                if (resEntity != null) {
                    result = EntityUtils.toString(resEntity, charset);
                }
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return result;
    }

    public static String postByStringBody(String url, String paramText, boolean needResponse){
        String responseStr = "";
        //post请求返回结果
        HttpClient httpClient = HttpClients.createDefault();
//        JSONObject jsonResult = null;
        HttpPost method = new HttpPost(url);

        try {
            if (null != paramText && paramText.length() > 0) {
                //解决中文乱码问题
                StringEntity entity = new StringEntity(paramText.toString(), "utf-8");
                entity.setContentEncoding("UTF-8");
                entity.setContentType("application/json");
                method.setEntity(entity);
            }
            HttpResponse result = httpClient.execute(method);
            url = URLDecoder.decode(url, "UTF-8");
            /**请求发送成功，并得到响应**/
            if (result.getStatusLine().getStatusCode() == 200) {
                String str = "";
                try {
                    /**读取服务器返回过来的json字符串数据**/
                    responseStr = EntityUtils.toString(result.getEntity());
                    if (!needResponse) {
                        return null;
                    }
                } catch (Exception e) {
                    logger.error("post请求提交失败:" + url);
                }
            }

        } catch (IOException e) {
            logger.error("post请求提交失败:" + url);
        }
        return responseStr;
    }

}

调用该方法代码段

        String accountUrl = "http://*********url";
        HashMap params = new HashMap();
        params.put("userId", userId);
        params.put("token", token);
        params.put("os", "weixin");
        params.put("version", ConfigUtils.getVersion());
        params.put("mac", "weixin");
        params.put("model", "weixin");
        params.put("from", "d");
        String reuslt = HttpClientUtil.doPost(accountUrl, params, "UTF-8");
                reuslt = reuslt.contains("html")?"{}":reuslt;
        logger.info("[getAccount]userId:{},result:{}",new Object[]{userId,reuslt});
        JSONObject jsonObject = JSON.parseObject(reuslt);
        /***
         * {"data":{"username":"[email protected]"},"message":"sucess","status":0}
         */
        if (jsonObject.getInteger("status") == 0) {
            String username = jsonObject.getJSONObject("data").getString("username");
            return username;
        }else {
            return "";
        }

此时返回的reuslt结果便是发送该请求获取到的请求。