java - HttpURLConnection 发送post请求

缺乏、安全感 2022-02-04 08:39 343阅读 0赞

### java - HttpURLConnection 发送post请求 ###

最近在做访问第三方接口的模块，虽然之前做过，而且有很多工具类的支持，但是我也遇到了一个让我痛苦了半天的‘坑’  
首先先上最终好使并实现的代码：

public static String postJson(String requestUrl, String params) throws Exception { 
    		System.out.println(params);
    		System.out.println("发送的连接为:" + requestUrl);
    		URL url = new URL(requestUrl);
    		// 打开和URL之间的连接
    		HttpURLConnection connection = (HttpURLConnection) url.openConnection();
    		System.out.println("打开链接，开始发送请求" + new Date().getTime() / 1000);
    		connection.setRequestMethod("POST");
    		// 设置通用的请求属性
    		connection.setRequestProperty("Content-Type", "application/json;charset=UTF-8");
    		connection.setRequestProperty("Connection", "Keep-Alive");
    		connection.setUseCaches(false);
    		connection.setDoOutput(true);
    		connection.setDoInput(true);
    
    		// 得到请求的输出流对象
    		DataOutputStream out = new DataOutputStream(connection.getOutputStream());
    		out.write(params.getBytes("UTF-8"));
    		out.flush();
    		out.close();
    
    		// 建立实际的连接
    		connection.connect();
    		// 获取所有响应头字段
    		Map<String, List<String>> headers = connection.getHeaderFields();
    		// 遍历所有的响应头字段
    		for (String key : headers.keySet()) { 
    			System.out.println(key + "--->" + headers.get(key));
    		}
    		// 定义 BufferedReader输入流来读取URL的响应
    		BufferedReader in = null;
    		if (requestUrl.contains("nlp"))
    			in = new BufferedReader(new InputStreamReader(connection.getInputStream(), "GBK"));
    		else
    			in = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
    		String result = "";
    		String getLine;
    		while ((getLine = in.readLine()) != null) { 
    			result += getLine;
    		}
    		in.close();
    		System.out.println("请求结束" + new Date().getTime() / 1000);
    		System.out.println("result:" + result);
    		return result;
    		
    		
    	}

这是我最终好使的代码，解决的坑是啥呢，先放报错的信息，大致是这个异常：  
Could not read document: Invalid UTF-8 start byte 0xbd\\n at \[Source: java.io.PushbackInputStream@29bb94d1; line: 1  
解决方式：见 [https://blog.csdn.net/weixin\_36775115/article/details/89918068][https_blog.csdn.net_weixin_36775115_article_details_89918068]

[https_blog.csdn.net_weixin_36775115_article_details_89918068]: https://blog.csdn.net/weixin_36775115/article/details/89918068