HttpClient (apache 子项目 http请求帮助工具包）

HttpClient (apache 子项目 http请求帮助工具包）

1.导入HttpClient相关的maven依赖
2.核心API:
2.1 HttpClient
2.2 HttpClients
2.3 CloseableHttpClient
2.4 HttpGet
2.5 HttpPost

// 创建Httpclient对象
CloseableHttpClient httpClient = HttpClients.createDefault();
String result = "";

//创建GET请求
HttpGet httpGet = new HttpGet(uri);

//发送请求
CloseableHttpResponse response = httpClient.execute(httpGet);

//判断响应状态
if(response.getStatusLine().getStatusCode() == 200){
result = EntityUtils.toString(response.getEntity(),"UTF-8");
}

3.demo HttpClientUtil.java

pom依赖：

org.apache.httpcomponents httpclient 4.5.10

HttpClientUtil.java;

import com.alibaba.fastjson.JSONObject;
import org.apache.http.NameValuePair;
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.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.util.EntityUtils;

import java.io.IOException;
import java.net.URI;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/**

• Http工具类
  */
  public class HttpClientUtil {

  static final int TIMEOUT_MSEC = 5 * 1000;

  /**

  • 发送GET方式请求

  • @param url

  • @param paramMap

  • @return
    */
    public static String doGet(String url,Map<String,String> paramMap){
    // 创建Httpclient对象
    CloseableHttpClient httpClient = HttpClients.createDefault();

    String result = "";
    CloseableHttpResponse response = null;

    try{
    URIBuilder builder = new URIBuilder(url);
    if(paramMap != null){
    for (String key : paramMap.keySet()) {
    builder.addParameter(key,paramMap.get(key));
    }
    }
    URI uri = builder.build();

     //创建GET请求
     HttpGet httpGet = new HttpGet(uri);
    
     //发送请求
     response = httpClient.execute(httpGet);
    
     //判断响应状态
     if(response.getStatusLine().getStatusCode() == 200){
         result = EntityUtils.toString(response.getEntity(),"UTF-8");
     }
    

    }catch (Exception e){
    e.printStackTrace();
    }finally {
    try {
    response.close();
    httpClient.close();
    } catch (IOException e) {
    e.printStackTrace();
    }
    }

    return result;
    }

  /**

  • 发送POST方式请求

  • @param url

  • @param paramMap

  • @return

  • @throws IOException
    */
    public static String doPost(String url, Map<String, String> paramMap) throws IOException {
    // 创建Httpclient对象
    CloseableHttpClient httpClient = HttpClients.createDefault();
    CloseableHttpResponse response = null;
    String resultString = "";

    try {
    // 创建Http Post请求
    HttpPost httpPost = new HttpPost(url);

     // 创建参数列表
     if (paramMap != null) {
         List<NameValuePair> paramList = new ArrayList();
         for (Map.Entry<String, String> param : paramMap.entrySet()) {
             paramList.add(new BasicNameValuePair(param.getKey(), param.getValue()));
         }
         // 模拟表单
         UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paramList);
         httpPost.setEntity(entity);
     }
    
     httpPost.setConfig(builderRequestConfig());
    
     // 执行http请求
     response = httpClient.execute(httpPost);
    
     resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
    

    } catch (Exception e) {
    throw e;
    } finally {
    try {
    response.close();
    } catch (IOException e) {
    e.printStackTrace();
    }
    }

    return resultString;
    }

  /**

  • 发送POST方式请求

  • @param url

  • @param paramMap

  • @return

  • @throws IOException
    */
    public static String doPost4Json(String url, Map<String, String> paramMap) throws IOException {
    // 创建Httpclient对象
    CloseableHttpClient httpClient = HttpClients.createDefault();
    CloseableHttpResponse response = null;
    String resultString = "";

    try {
    // 创建Http Post请求
    HttpPost httpPost = new HttpPost(url);

     if (paramMap != null) {
         //构造json格式数据
         JSONObject jsonObject = new JSONObject();
         for (Map.Entry<String, String> param : paramMap.entrySet()) {
             jsonObject.put(param.getKey(),param.getValue());
         }
         StringEntity entity = new StringEntity(jsonObject.toString(),"utf-8");
         //设置请求编码
         entity.setContentEncoding("utf-8");
         //设置数据类型
         entity.setContentType("application/json");
         httpPost.setEntity(entity);
     }
    
     httpPost.setConfig(builderRequestConfig());
    
     // 执行http请求
     response = httpClient.execute(httpPost);
    
     resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
    

    } catch (Exception e) {
    throw e;
    } finally {
    try {
    response.close();
    } catch (IOException e) {
    e.printStackTrace();
    }
    }

    return resultString;
    }
    private static RequestConfig builderRequestConfig() {
    return RequestConfig.custom()
    .setConnectTimeout(TIMEOUT_MSEC)
    .setConnectionRequestTimeout(TIMEOUT_MSEC)
    .setSocketTimeout(TIMEOUT_MSEC).build();
    }

}