Java发送HTTP 请求

不念不忘少年蓝@ 2022-03-02 01:40 302阅读 0赞

## 前言 ##

请求http的Demo是个人亲测过，目前该方式已经在线上运行着。因为是http请求，所有发送post 和get 请求的demo都有在下方贴出，包括怎么测试，大家可直接 copy到自己的项目中使用。

## 正文 ##

**使用须知**

为了避免大家引错包我把依赖和涉及到包路径给大家

import java.net.HttpURLConnection;
    import java.net.URI;
    
    import org.apache.http.HttpResponse;
    import org.apache.http.HttpStatus;
    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.DefaultHttpClient;
    import org.apache.http.impl.client.HttpClients;
    import org.apache.http.util.EntityUtils;
    
    
    import com.fasterxml.jackson.databind.ObjectMapper;

<dependency>
    			<groupId>org.apache.httpcomponents</groupId>
    			<artifactId>httpcore</artifactId>
    			<version>4.4.8</version>
    		</dependency>
    		<dependency>
    			<groupId>org.apache.httpcomponents</groupId>
    			<artifactId>httpclient</artifactId>
    			<version>4.5.3</version>
    		</dependency>

### HTTP 发送 get 请求 ###

首先我们引入两个包

**发送get请求的工具类，可直接 copy 使用即可**

另外，我抛出异常的代码大家改成自己业务的异常，不需要就删除掉。

参数说明：

host：ip

servUri：url

reString：参数

public static String getHttpData(String host, String servUri, String reString) throws Exception {
    		StringBuffer sb = new StringBuffer();
    		sb.append("getHttpData:host:" + host + ",servUri:" + servUri + ",reString:" + reString);
    		String strResp = null;
    		try {
    			URI uri = new URIBuilder().setScheme("http").setHost(host).setPath(servUri)
    					.setParameter("strInfo", reString).build();
    			HttpGet httpGet = new HttpGet(uri);
    			CloseableHttpClient client3 = HttpClients.createDefault();
    			HttpResponse resp;
    			resp = client3.execute(httpGet);
    			if (resp.getStatusLine().getStatusCode() == HttpURLConnection.HTTP_OK) {
    				strResp = EntityUtils.toString(resp.getEntity());
    				logger.info("the return result:{}", strResp);
    			} else {
    				logger.info("Error Response:", resp.getStatusLine().toString());
    				throw new CommonBusinessException(CommonConstants.TASK_RELEASE_WCF,
    						CommonConstants.TASK_RELEASE_WCF_DESC);
    			}
    		} catch (Exception e) {
    			logger.error(sb.toString() + ":" + e.getMessage(), e.getCause());
    			throw new CommonBusinessException(CommonConstants.TASK_RELEASE_WCF, CommonConstants.TASK_RELEASE_WCF_DESC);
    		}
    		return strResp;
    	}

### HTTP 发送 post 请求 ###

发送post分两种,我分两种的原因是为了让大家方便，想传对象和 json 可以直接复制过用就可以用，不用你们在转了。

**第一种是直接接收json**

参数明说：

url：url

json：参数

public static String doPostData(String url, String json) throws Exception {
    		DefaultHttpClient client = new DefaultHttpClient();
    		HttpPost post = new HttpPost(url);
    		String result = "";
    		HttpResponse res = null;
    		try {
    			StringEntity s = new StringEntity(json.toString(), "UTF-8");
    			s.setContentType("application/json");
    			post.setHeader("Accept", "application/json");
    			post.setHeader("Content-type", "application/json; charset=utf-8");
    			post.setEntity(s);
    			res = client.execute(post);
    			if (res.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
    				result = EntityUtils.toString(res.getEntity());
    				return HttpStatus.SC_OK + "";
    			}
    		} catch (Exception e) {
    			if(res == null) {
    				return "HttpResponse 为 null!";
    			}
    			throw new RuntimeException(e);
    		}
    		if(res == null || res.getStatusLine() == null) {
    			return "无响应";
    		}
    		return res.getStatusLine().getStatusCode() + "";
    	}

测试

@Test
        public void test12() throws Exception {
            String HOST = "http://eipwcf.aspirecn.com/SvcEF/Service1.svc/WCF_EF_MSA_GetDataInfo_P";
            HttpClient client = new HttpClient();
            JSONObject json = new JSONObject();
            json.put("msgId", msgId);
            String reslut=client.doPostData(HOST, json);
        }

**第二种是参数是对象**

参数说明：

url：url

tram：对象

public static String doHttpPostData(String url, TaskReleaseApprovalModel tram)
    			throws Exception {
    		StringBuffer sb = new StringBuffer();
    		sb.append("doHttpPostData:url:" + url + ",tram:" + tram.toString() + ",contentType:" + contentType);
    		logger.info(sb.toString());
    		String tmpString = "";
    		HttpPost request = new HttpPost(url);
    		request.setHeader("Accept", "application/json");
    		request.setHeader("Content-type", "application/json");
    		ObjectMapper mapper = new ObjectMapper();
    		String jsonString;
    		try {
    			jsonString = mapper.writeValueAsString(tram);
    			StringEntity entity = new StringEntity(jsonString, "UTF-8");
    			request.setEntity(entity);
    			CloseableHttpClient client = HttpClients.createDefault();
    			HttpResponse response = client.execute(request);
    			if (response.getStatusLine().getStatusCode() == HttpURLConnection.HTTP_OK) {
    				tmpString = EntityUtils.toString(response.getEntity());
    				logger.info("the post result:tmpString:{}", tmpString);
    			} else {
    				logger.info("the post failure:tmpString:", tmpString);
    				throw new CommonBusinessException(CommonConstants.TASK_RELEASE_WCF,
    						CommonConstants.TASK_RELEASE_WCF_DESC);
    			}
    		} catch (Exception e) {
    			logger.error(sb.toString() + ":" + e.getMessage(), e.getCause());
    			throw new CommonBusinessException(CommonConstants.TASK_RELEASE_POSTWCF,
    					CommonConstants.TASK_RELEASE_POSTWCF_DESC);
    		}
    		return tmpString;
    	}

这个方法我想不用写测试类大家也会用，传过去对象和地址就可以了，很方便很简单。