Java调用Http/Https接口(1)--编写服务端

　　Http接口输入的数据一般是键值对或json数据，返回的一般是json数据。本系列文章主要介绍Java调用Http接口的各种方法，本文主要介绍服务端的编写，方便后续文章里的客户端的调用。文中所使用到的软件版本：Java 1.8.0_191、SpringBoot 2.2.1.RELEASE。

1、服务端Controller

package com.inspur.demo.http.server; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.InputStream; import java.io.OutputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.multipart.MultipartFile; import com.inspur.demo.common.entity.CallResult; import com.inspur.demo.common.util.FileUtil; import com.inspur.demo.http.entity.User; @Controller @RequestMapping(value="/httptest/", method = {RequestMethod.GET, RequestMethod.POST}) public class HttpTestController { private static Logger logger = LoggerFactory.getLogger(HttpTestController.class); @RequestMapping(value = "getUser", produces = "application/json;charset=UTF-8") @ResponseBody public CallResult<User> getUser(String userId, String userName) { logger.info("userId={},userName={}", userId, userName); User user = new User(); user.setUserId(userId); user.setUserName(userName); CallResult<User> result = new CallResult<User>(0, "OK", user); return result; } /** * 传入json * @param user * @return */ @RequestMapping("addUser") @ResponseBody public CallResult<User> addUser(@RequestBody User user) { logger.info(user.toString()); CallResult<User> result = new CallResult<User>(0, "OK", user); return result; } /** * 上传文件 * 这种方式不适合页面form表单上传文件，适合客户端调用 * @param request * @return */ @RequestMapping(value = "upload", produces = "application/json;charset=UTF-8") @ResponseBody public CallResult<String> upload(HttpServletRequest request) { InputStream in = null; OutputStream out = null; CallResult<String> result = new CallResult<String>(0, "OK", "上传成功"); try { in = new BufferedInputStream(request.getInputStream(), 16 * 1024); //假设上传的就是jpg文件 String fileName = "d:/temp/upload_" + System.currentTimeMillis() + ".jpg"; out = new BufferedOutputStream(new FileOutputStream(fileName), 16 * 1024); byte[] buffer = new byte[16 * 1024]; int len = 0; while ((len = in.read(buffer)) != -1) { out.write(buffer, 0, len); } } catch (Exception e) { result = new CallResult<String>(-1, "发生异常", ""); e.printStackTrace(); } finally { FileUtil.close(in); FileUtil.close(out); } logger.info("upload返回结果：{}", result); return result; } /** * 上传文件及发送键值对数据 * @param file * @param param1 * @param param2 * @return */ @RequestMapping("multi") @ResponseBody public CallResult<String> multi(@RequestParam("file") MultipartFile file, String param1, String param2) { logger.info("file={},param1={},param2={}", file.getOriginalFilename(), param1, param2); InputStream in = null; OutputStream out = null; CallResult<String> result = new CallResult<String>(0, "OK", "上传成功"); try { in = new BufferedInputStream(file.getInputStream(), 16 * 1024); String originalFilename = file.getOriginalFilename(); //ie上传文件该值是全路径，处理下 if (originalFilename.indexOf("\\") > -1) { originalFilename = originalFilename.substring(originalFilename.indexOf("\\") + 1); } String fileName = "d:/temp/multi_" + System.currentTimeMillis() + "_" + originalFilename; out = new BufferedOutputStream(new FileOutputStream(fileName), 16 * 1024); byte[] buffer = new byte[16 * 1024]; int len = 0; while ((len = in.read(buffer)) != -1) { out.write(buffer, 0, len); } } catch (Exception e) { result = new CallResult<String>(-1, "发生异常", ""); e.printStackTrace(); } finally { FileUtil.close(in); FileUtil.close(out); } logger.info("multi返回结果：{}", result); return result; } /** * 下载文件 * @param request * @param response */ @RequestMapping("download") public void download(HttpServletRequest request, HttpServletResponse response) { int BUFFER_SIZE = 16 * 1024; BufferedInputStream bis = null; OutputStream out = null; try { String fileName = "a.jpg"; String urlFileName = ""; if (request.getHeader("User-Agent").toLowerCase().indexOf("firefox") > 0) { urlFileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1"); } else { urlFileName = java.net.URLEncoder.encode(fileName, "UTF-8"); } response.reset(); response.setContentType("application/octet-stream"); response.setHeader("Content-Disposition", "attachment; filename=\"" + urlFileName + "\""); response.setHeader("Connection", "close"); bis = new BufferedInputStream(new FileInputStream("d:/" + fileName), BUFFER_SIZE); out = new BufferedOutputStream(response.getOutputStream(), BUFFER_SIZE); byte buf[] = new byte[BUFFER_SIZE]; int len; while ((len = bis.read(buf)) != -1) { out.write(buf, 0, len); } } catch (Exception e) { e.printStackTrace(); } finally { FileUtil.close(bis); FileUtil.close(out); } } }