开发的时候碰到这样的需求：需要在一个系统（客户端发送请求）中将文件传输至另外一个系统（服务端接收）中去的实现方式，可以批量传输文件，代码如下：
客户端请求：
public String upLoadFilePost(String actionUrl, Map<String, File> files) throws IOException {
String BOUNDARY = java.util.UUID.randomUUID().toString();
String PREFIX = "--", LINEND = "\r\n";
String MULTIPART_FROM_DATA = "multipart/form-data";
String CHARSET = "UTF-8";
URL uri = new URL(actionUrl);
HttpURLConnection conn = (HttpURLConnection) uri.openConnection();
conn.setReadTimeout(5 * 1000);
conn.setDoInput(true);// 允许输入
conn.setDoOutput(true);// 允许输出
conn.setUseCaches(false);
conn.setRequestMethod("POST"); // Post方式
conn.setRequestProperty("connection", "keep-alive");
conn.setRequestProperty("Charsert", "UTF-8");
conn.setRequestProperty("Content-Type", MULTIPART_FROM_DATA
+ ";boundary=" + BOUNDARY);
DataOutputStream outStream = new DataOutputStream(
conn.getOutputStream());
// 发送文件数据
if (files != null)
for (Map.Entry<String, File> file : files.entrySet()) {
StringBuilder sb1 = new StringBuilder();
sb1.append(PREFIX);
sb1.append(BOUNDARY);
sb1.append(LINEND);
sb1.append("Content-Disposition: form-data; name=\"file\"; filename=\""
+ file.getKey() + "\"" + LINEND);
sb1.append("Content-Type: application/octet-stream; charset="
+ CHARSET + LINEND);
sb1.append(LINEND);
outStream.write(sb1.toString().getBytes());
InputStream is = new FileInputStream(file.getValue());
byte[] buffer = new byte[1024];
int len = 0;
while ((len = is.read(buffer)) != -1) {
outStream.write(buffer, 0, len);
}
is.close();
outStream.write(LINEND.getBytes());
}
// 请求结束标志
byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINEND).getBytes();
outStream.write(end_data);
outStream.flush();
// 得到响应码
int res = conn.getResponseCode();
if (res == 200) {
InputStream in = conn.getInputStream();
InputStreamReader isReader = new InputStreamReader(in);
BufferedReader bufReader = new BufferedReader(isReader);
String line = "";
String data = "";
while ((line = bufReader.readLine()) != null) {
data += line;
}
outStream.close();
conn.disconnect();
return data;
}
outStream.close();
conn.disconnect();
return null;
}服务端接收接口方法体：
public String fileInteraction(HttpServletRequest request, HttpServletResponse response) throws Exception {
//操作成功则返回OK
String result = "";
MultipartHttpServletRequest multiRequest = (MultipartHttpServletRequest) request;
//解析request，将结果放置在list中
Map<String, List<MultipartFile>> fileMap = multiRequest.getMultiFileMap();
for (String key : fileMap.keySet()) {
List<MultipartFile> files = fileMap.get(key);
for (MultipartFile file : files) {
if (!file.isEmpty()) {
String fileNamePath = file.getOriginalFilename();
String[] params = fileNamePath.split("\\.");
String filename = "";
int i = 0;
for (String str : params) {
i = i + 1;
if (StringUtils.isNotEmpty(filename)) {
if (i==params.length) {
filename = filename + "." + str;
}else{
filename = filename + "/" + str;
}
}else{
filename = str;
}
}
// 文件保存路径
String filePath = request.getSession().getServletContext().getRealPath("/") + "upload/wxfile/" + filename;
File iFile = new File(filePath);
File iFileParent = iFile.getParentFile();
if(!iFileParent.exists()){
iFileParent.mkdirs();
}
// 转存文件
file.transferTo(new File(filePath));
result = "ok";
}
}
}
return result;
}调用客户端调用发送请求方法：
String actionUrl = "http://shuilangyizu.iask.in/liuf/utilController/fileInteraction.do";
Map<String, File> files = new HashMap<String, File>();
File file = new File(request.getSession().getServletContext().getRealPath("/") + "upload/temp/1.doc");
files.put("x."+file.getName(), file);
File file2 = new File(request.getSession().getServletContext().getRealPath("/") + "upload/temp/1.jpg");
files.put("y."+file2.getName(), file2);
String result = utilService.upLoadFilePost(actionUrl, files);
