使用HttpClientUtil工具类调用第三方接口

╰半橙微兮° 2022-10-08 11:29 224阅读 0赞

工具类：

package com.newtouch.product.transfer.utils;
    
    
    import java.io.IOException;
    import java.net.URI;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Map;
    
    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.client.utils.URIBuilder;
    import org.apache.http.entity.ContentType;
    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;
    
    
    public class HttpClientUtil { 
        /** * 带参数的get请求 * @param url * @param param * @return String */
        public static String doGet(String url, Map<String, String> param) { 
            // 创建Httpclient对象
            CloseableHttpClient httpclient = HttpClients.createDefault();
    
            String resultString = "";
            CloseableHttpResponse response = null;
            try { 
                // 创建uri
                URIBuilder builder = new URIBuilder(url);
                if (param != null) { 
                    for (String key : param.keySet()) { 
                        builder.addParameter(key, param.get(key));
                    }
                }
                URI uri = builder.build();
                // 创建http GET请求
                HttpGet httpGet = new HttpGet(uri);
                // 执行请求
                response = httpclient.execute(httpGet);
                // 判断返回状态是否为200
                if (response.getStatusLine().getStatusCode() == 200) { 
                    resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
                }
            } catch (Exception e) { 
                e.printStackTrace();
            } finally { 
                try { 
                    if (response != null) { 
                        response.close();
                    }
                    httpclient.close();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
            return resultString;
        }
    
        /** * 不带参数的get请求 * @param url * @return String */
        public static String doGet(String url) { 
            return doGet(url, null);
        }
    
        /** * 带参数的post请求 * @param url * @param param * @return String */
        public static String doPost(String url, Map<String, String> param) { 
            // 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 (param != null) { 
                    List<NameValuePair> paramList = new ArrayList<>();
                    for (String key : param.keySet()) { 
                        paramList.add(new BasicNameValuePair(key, param.get(key)));
                    }
                    // 模拟表单
                    UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paramList);
                    httpPost.setEntity(entity);
                }
                // 执行http请求
                response = httpClient.execute(httpPost);
                resultString = EntityUtils.toString(response.getEntity(), "utf-8");
            } catch (Exception e) { 
                e.printStackTrace();
            } finally { 
                try { 
                    response.close();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
            return resultString;
        }
    
        /** * 不带参数的post请求 * @param url * @return String */
        public static String doPost(String url) { 
            return doPost(url, null);
        }
    
        /** * 传送json类型的post请求 * @param url * @param json * @return String */
        public static String doPostJson(String url, String json) { 
            // 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);
                // 创建请求内容
                StringEntity entity = new StringEntity(json, ContentType.APPLICATION_JSON);
                httpPost.setEntity(entity);
                // 执行http请求
                response = httpClient.execute(httpPost);
                resultString = EntityUtils.toString(response.getEntity(), "utf-8");
            } catch (Exception e) { 
                e.printStackTrace();
            } finally { 
                try { 
                    response.close();
                } catch (IOException e) { 
                    e.printStackTrace();
                }
            }
            return resultString;
        }
    }

下面是工具类的调用方法：

@RequestMapping(value="/v1.0/httpUtil", method = RequestMethod.POST, produces ="application/json;charset=UTF-8")
        public String  httpUtil(@RequestBody String req) throws JSONException{ 
                String url = "http://192.168.1.249:38081/security/v1.0/queryInformation" ;
    			/* Map<String,String > map = new HashMap<>(); map.put("openId","h"); String jsonObj = JsonUtils.toJson(map);*/
                String result = HttpClientUtil.doPostJson(url,req);
                System.out.println("请求结果：" + result);
                return result;
        }

上述代码测试时可以直接放到controller层中。

实际使用时，遵循上述用法即可。  
另，传参和返回值可以视情况而定。

测试过程中遇到的问题：  
1、注意在访问第三方接口时要确保对方服务器已经关闭防火墙；  
2、url必须要加端口号否则无法访问到；  
3、\*\*这条适用于任何项目：\*\*当同时打开多个工程时，要确定当前运行的确实是我们想要测试的项目。

原文链接：https://blog.csdn.net/MichaelSuns/article/details/106124039