java发送http请求，get，post，delete

package com.odianyun.example.business.common.utils;

import com.alibaba.fastjson.JSON;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.config.RequestConfig;
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.client.utils.URIBuilder;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.ssl.SSLContextBuilder;
import org.apache.http.ssl.TrustStrategy;
import org.apache.http.util.EntityUtils;

import javax.net.ssl.SSLContext;
import java.io.IOException;
import java.security.KeyManagementException;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.*;

/**
 * 模拟http请求工具类
 *
 * @author matao
 * @date 2016年7月14日
 */
public class HttpClientUtils {
   private static CloseableHttpClient httpClient = createSSLClientDefault();

   static int time=2000;
   /**
    * 发送GET请求
    *
    * @author matao
    * @date 2016年7月19日
    */
   public static String sendGet(String url) {
      String responseContent = "";

      HttpGet httpGet = new HttpGet(url);

      try {
         RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(time).setConnectionRequestTimeout(time).setSocketTimeout(time).build();
         httpGet.setConfig(requestConfig);
         HttpResponse response = httpClient.execute(httpGet);

         if (response == null) {
            return responseContent;
         }

         // 获得响应实体
         HttpEntity resEntity = response.getEntity();
         // 获得状态码
         int statusCode = response.getStatusLine() == null ? 0 : response.getStatusLine().getStatusCode();
         // 获得相应内容
         if (resEntity != null && statusCode == 200) {
            responseContent = EntityUtils.toString(response.getEntity(), "UTF-8");
         }
      } catch (ClientProtocolException e) {
         e.printStackTrace();
      } catch (IOException e) {
         e.printStackTrace();
      }

      return responseContent;
   }

   /**
    * 发送post数据类型为form-data
    * @param url
    * @param map
    * @return
    * @throws Exception
    */
   public static String doPost(String url, HashMap<String, String> map) throws Exception {
      String result = "";
      CloseableHttpClient client = null;
      CloseableHttpResponse response = null;
      RequestConfig defaultRequestConfig = RequestConfig.custom().setSocketTimeout(550000).setConnectTimeout(550000)
            .setConnectionRequestTimeout(550000).setStaleConnectionCheckEnabled(true).build();
      client = HttpClients.custom().setDefaultRequestConfig(defaultRequestConfig).build();
      // client = HttpClients.createDefault();
      URIBuilder uriBuilder = new URIBuilder(url);
      HttpPost httpPost = new HttpPost(uriBuilder.build());
      httpPost.setHeader("Connection", "Keep-Alive");
      httpPost.setHeader("Charset", "UTF-8");
      httpPost.setHeader("Content-Type", "application/x-www-form-urlencoded");
      Iterator<Map.Entry<String, String>> it = map.entrySet().iterator();
      List<NameValuePair> params = new ArrayList<NameValuePair>();
      while (it.hasNext()) {
         Map.Entry<String, String> entry = it.next();
         NameValuePair pair = new BasicNameValuePair(entry.getKey(), entry.getValue());
         params.add(pair);
      }
      httpPost.setEntity(new UrlEncodedFormEntity(params, "UTF-8"));
      try {
         response = client.execute(httpPost);
         if (response != null) {
            HttpEntity resEntity = response.getEntity();
            if (resEntity != null) {
               result = EntityUtils.toString(resEntity, "UTF-8");
            }
         }
      } catch (ClientProtocolException e) {
         throw new RuntimeException("创建连接失败" + e);
      } catch (IOException e) {
         throw new RuntimeException("创建连接失败" + e);
      }

      return result;

   }

   public static String doDelete(String data, String url) throws IOException {
      CloseableHttpClient client = null;
      com.odianyun.example.business.common.utils.HttpDeleteWithBody httpDelete = null;
      String result = null;
      try {
         client = HttpClients.createDefault();
         httpDelete = new com.odianyun.example.business.common.utils.HttpDeleteWithBody(url);

         httpDelete.addHeader("Content-type","application/json; charset=utf-8");
         httpDelete.setHeader("Accept", "application/json; charset=utf-8");
         httpDelete.setEntity(new StringEntity(data));

         CloseableHttpResponse response = client.execute(httpDelete);
         HttpEntity entity = response.getEntity();
         result = EntityUtils.toString(entity);

         if (200 == response.getStatusLine().getStatusCode()) {

         }
      } catch (Exception e) {
      } finally {
         client.close();
      }
      return result;

   }




   public static String sendPost(String url, Object params) {
      // 响应内容
      String responseContent = "";

      HttpPost post = new HttpPost(url);

      try {
         // 设置请求实体
         StringEntity reqEntity = new StringEntity(JSON.toJSONString(params), "utf-8");
         reqEntity.setContentEncoding("UTF-8");
         reqEntity.setContentType("application/json");
         post.setEntity(reqEntity);



         // 发送请求，返回响应对象
         HttpResponse response = httpClient.execute(post);

         if (response == null) {
            return responseContent;
         }

         // 获得响应实体
         HttpEntity resEntity = response.getEntity();
         // 获得状态码
         int statusCode = response.getStatusLine() == null ? 0 : response.getStatusLine().getStatusCode();
         // 获取响应内容
         if (resEntity != null && statusCode == HttpStatus.SC_OK) {
            responseContent = EntityUtils.toString(resEntity, "UTF-8");
         }
      } catch (ClientProtocolException e) {
         e.printStackTrace();
      } catch (IOException e) {
         e.printStackTrace();
      }catch (Exception ec){
         ec.printStackTrace();
      }

      return responseContent;
   }


   public static String sendFormPost(String url, String params) {
      // 响应内容
      String responseContent = "";

      HttpPost post = new HttpPost(url);

      try {

         // 设置请求实体
         StringEntity reqEntity = new StringEntity(params, "utf-8");
         reqEntity.setContentEncoding("UTF-8");
         reqEntity.setContentType("application/x-www-form-urlencoded");
         post.setEntity(reqEntity);



         // 发送请求，返回响应对象
         HttpResponse response = httpClient.execute(post);

         if (response == null) {
            return responseContent;
         }

         // 获得响应实体
         HttpEntity resEntity = response.getEntity();
         // 获得状态码
         int statusCode = response.getStatusLine() == null ? 0 : response.getStatusLine().getStatusCode();
         // 获取响应内容
         if (resEntity != null && statusCode == HttpStatus.SC_OK) {
            responseContent = EntityUtils.toString(resEntity, "UTF-8");
         }
      } catch (ClientProtocolException e) {
         e.printStackTrace();
      } catch (IOException e) {
         e.printStackTrace();
      }catch (Exception ec){
         ec.printStackTrace();
      }

      return responseContent;
   }

   /**
    * 创建HttpClient对象（用于发送https请求）
    *
    * @author matao
    * @date 2016年7月14日
    */
   public static CloseableHttpClient createSSLClientDefault() {
      try {
         TrustStrategy trustStrategy = new TrustStrategy() {
            public boolean isTrusted(X509Certificate[] chain, String authType) throws CertificateException {
               return true;
            }
         };

         SSLContext sslContext = new SSLContextBuilder().loadTrustMaterial(null, trustStrategy).build();
         SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext);
         return HttpClients.custom().setSSLSocketFactory(sslsf).build();
      } catch (KeyManagementException e) {
         e.printStackTrace();
      } catch (NoSuchAlgorithmException e) {
         e.printStackTrace();
      } catch (KeyStoreException e) {
         e.printStackTrace();
      }

      return HttpClients.createDefault();
   }

   public static void main(String[] args) {
      String result = sendFormPost("https://www.XXX.com/forecom/login/ajax_b2b.shtml","username=1&password=1");

      System.out.println(result);
   }

}

上面的代码可以发送http的get以及post，如果需要发送delete则需要下面的类

package com.odianyun.example.business.common.utils;

/**
 * @ Author     ：kxs.
 * @ Date       ：Created in 14:30 2020/7/22
 * @ Description：${description}
 * @ Modified By：
 * @Version: $version$
 */
import java.net.URI;

import org.apache.http.client.methods.HttpEntityEnclosingRequestBase;

public class HttpDeleteWithBody extends HttpEntityEnclosingRequestBase{
    public static final String METHOD_NAME = "DELETE";

    /**
     * 获取方法（必须重载）
     *
     * @return
     */
    @Override
    public String getMethod() {
        return METHOD_NAME;
    }

    public HttpDeleteWithBody(final String uri) {
        super();
        setURI(URI.create(uri));
    }

    public HttpDeleteWithBody(final URI uri) {
        super();
        setURI(uri);
    }

    public HttpDeleteWithBody() {
        super();
    }

}

 发送post请求form-data格式的请求需要将对象转为Map<String, String>，参考链接：https://www.cnblogs.com/mm962464/p/13363313.html