利用HttpUrlConnection 上传 接收文件方法

//客户端代码

public static void main(String[] args) throws IOException {
DataInputStream in = null;
OutputStream out = null;
HttpURLConnection conn = null;
JSONObject resposeTxt = null;
InputStream ins = null;
ByteArrayOutputStream outStream = null;
try {
URL url = new URL("http://10.28.160.160:9080/main/uploadFile?fileName=列表.txt");
conn = (HttpURLConnection) url.openConnection();
// 发送POST请求必须设置如下两行
conn.setDoOutput(true);
conn.setUseCaches(false);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "text/html");
conn.setRequestProperty("Cache-Control", "no-cache");
conn.setRequestProperty("Charsert", "UTF-8");
conn.connect();
conn.setConnectTimeout(10000);
out = conn.getOutputStream();

File file = new File("H:/Users/chengtingyu/Desktop/test/list.txt");
in = new DataInputStream(new FileInputStream(file));

int bytes = 0;
byte[] buffer = new byte[1024];
while ((bytes = in.read(buffer)) != -1) {
out.write(buffer, 0, bytes);
}
out.flush();

// 返回流
if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
ins = conn.getInputStream();
outStream = new ByteArrayOutputStream();
byte[] data = new byte[1024];
int count = -1;
while ((count = ins.read(data, 0, 1024)) != -1) {
outStream.write(data, 0, count);
}
data = null;
resposeTxt = JSONObject.parseObject(new String(outStream
.toByteArray(), "UTF-8"));
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (in != null) {
in.close();
}
if (out != null) {
out.close();
}
if (ins != null) {
ins.close();
}
if (outStream != null) {
outStream.close();
}
if (conn != null) {
conn.disconnect();
}
}
}

//服务端代码

public String uploadFile() throws Exception{
String fileName = request.getParameter("fileName");
String fileFullPath = "H:/Users/chengtingyu/Desktop/" + fileName;
InputStream input = null;
FileOutputStream fos = null;
try {
input = request.getInputStream();
File file = new File("H:/Users/chengtingyu/Desktop");
if(!file.exists()){
file.mkdirs();
}
fos = new FileOutputStream(fileFullPath);
int size = 0;
byte[] buffer = new byte[1024];
while ((size = input.read(buffer,0,1024)) != -1) {
fos.write(buffer, 0, size);
}

//响应信息 json字符串格式
Map<String,Object> responseMap = new HashMap<String,Object>();
responseMap.put("flag", true);

//生成响应的json字符串
String jsonResponse = JSONObject.toJSONString(responseMap);
sendResponse(jsonResponse);
} catch (IOException e) {
//响应信息 json字符串格式
Map<String,Object> responseMap = new HashMap<String,Object>();
responseMap.put("flag", false);
responseMap.put("errorMsg", e.getMessage());
String jsonResponse = JSONObject.toJSONString(responseMap);
sendResponse(jsonResponse);
} finally{
if(input != null){
input.close();
}
if(fos != null){
fos.close();
}
}

return null;
}



/**
* 返回响应
*
* @throws Exception
*/
private void sendResponse(String responseString) throws Exception {
response.setContentType("application/json;charset=UTF-8");
PrintWriter pw = null;
try {
pw = response.getWriter();
pw.write(responseString);
pw.flush();
} finally {
IOUtils.closeQuietly(pw);
}
}