Apache HttpClient

1.下载apache client项目jar包  http://mirrors.tuna.tsinghua.edu.cn/apache//httpcomponents/httpclient/binary/httpcomponents-client-4.5.3-bin.tar.gz

   httpcomponents-client-4.5.3lib 下面的jar包

package com.service;

import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
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.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

import java.io.IOException;
import java.util.*;

public class ApacheHttpClientUtil {

    /**
     * 发送post请求
     *
     * @param url
     * @param parameters
     */
    public static void httpPost(String url, Map<String, String> parameters) {
        CloseableHttpClient httpclient = null;
        CloseableHttpResponse response = null;
        try {
            httpclient = HttpClientBuilder.create().build();
            HttpPost post = new HttpPost(url);

            // post 参数 传递
            if (parameters != null) {
                List<NameValuePair> list = new ArrayList<NameValuePair>();
                for (Map.Entry<String, String> map : parameters.entrySet()) {
                    String key = map.getKey().toString();
                    String value = map.getValue().toString();
                    list.add(new BasicNameValuePair(key, value));
                }
                post.setEntity(new UrlEncodedFormEntity(list, "utf-8"));
            }

            response = httpclient.execute(post);

            // 请求发送成功，并得到响应
            if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                //读取服务器返回过来的json字符串数据
                String strResult = EntityUtils.toString(response.getEntity());
                System.out.println(strResult);
            } else {
                System.out.println("请求失败");
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (response != null) {
                    response.close();
                }
                if (httpclient != null) {
                    httpclient.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static void httpGet(String url) {
        CloseableHttpClient httpclient = null;
        CloseableHttpResponse response = null;
        try {
            //发送get请求
            httpclient = HttpClientBuilder.create().build();
            HttpGet request = new HttpGet(url);
            response = httpclient.execute(request);

            /**请求发送成功，并得到响应**/
            if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                /**读取服务器返回过来的json字符串数据**/
                String strResult = EntityUtils.toString(response.getEntity());
                System.out.println(strResult);
            } else {
                System.out.println("请求失败");
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (response != null) {
                    response.close();
                }
                if (httpclient != null) {
                    httpclient.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}