需求：接收方需要接收json格式的数据，如下图。
传输json数据格式： 话不多说，上代码：完成需求全代码如下：
package xxxxxxxxxx; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.net.URL; import java.net.URLConnection; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.servlet.http.HttpServletRequest; import java.lang.StringBuilder; import java.io.BufferedReader; import com.alibaba.fastjson.JSONObject; public class Test2 { public static void main(String[] args) { String url = "http://xxxxxxxxxxxxxxx"; //备注：您请求对方接口的url地址 Map<String, Object> map = new HashMap<>(); map.put("packageName", "XXXXXXXXXX"); map.put("packageCode", "PMJJ-XXX"); map.put("aName", XXXXX"); map.put("aCode", "123456789012345678"); map.put("aMandator", "XXXX"); map.put("packageType", "XXX"); map.put("address", "XXXXXXXXXX"); map.put("plotCode", "190101010100002,190101010100003"); map.put("area", 5.96); map.put("areaUnit", "XX"); map.put("lease", 1); map.put("leaseUnit", "XX"); map.put("customType", "XXX"); map.put("useDescribe", "XX"); map.put("bName", "XX"); map.put("bCode", "987654321098765432"); map.put("finishPrice", 1000); map.put("noticeTime", "2020-05-21"); String param = ""; List<Map> extraFile = new ArrayList<>(); try { Map<String, Object> fileMap = new HashMap<>(); String base64 = null; File file = new File("C:/Desktop/水调歌头base64.txt"); //本地已转的base64格式的文件 FileInputStream fis; fis = new FileInputStream(file); byte[] byte64 = new byte[(int) file.length()]; fis.read(byte64); base64 = new String(byte64); fileMap.put("fileName", "xxxx.pdf"); //附件名称 fileMap.put("fileBase64", base64); extraFile.add(fileMap); map.put("extraFile", extraFile); param = JSONObject.toJSONString(map); System.out.println(param); PrintWriter out = null; BufferedReader in = null; String result = ""; URL realUrl = new URL(url); // 打开和URL之间的连接 URLConnection conn = realUrl.openConnection(); // 设置通用的请求属性 conn.setRequestProperty("accept", "*/*"); conn.setRequestProperty("connection", "Keep-Alive"); conn.setRequestProperty("Content-Type", "application/json"); //conn.setRequestProperty("Content-Type", "multipart/form-data"); conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); // 发送POST请求必须设置如下两行 conn.setDoOutput(true); conn.setDoInput(true); // 获取URLConnection对象对应的输出流 out = new PrintWriter(conn.getOutputStream()); // 发送请求参数 out.print(param); // flush输出流的缓冲 out.flush(); // 定义BufferedReader输入流来读取URL的响应 in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "utf-8")); String line; while ((line = in.readLine()) != null) { result += line; } System.out.println("----------------------------"); System.out.println(result); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } }运行输出结果如下：
{"area":5.96,"areaUnit":"XX","address":"XXXXXXX","bName":"XX","aMandator":"XXXX","bCode":"987654321098765432","extraFile":[{"fileName":"xxxxxx.pdf","fileBase64":"此处输出是base64格式编码，由于过长，省略。"}],"packageType":"XXXX","customType":"XXX","finishPrice":1000,"packageCode":"PMJJ-XXXXX1","aName":"XXXXXX","leaseUnit":"XX","aCode":"123456789012345678","packageName":"XXXXXXXXXX","lease":1,"useDescribe":"XXXX","noticeTime":"2020-05-21","plotCode":"190101010100002,190101010100003"}备注： base64转码可参考链接：https://www.zhangxinxu.com/sp/base64.html。直接拖文件进去即可。 base64,后面的即是图片转码后值。
