基于标准http实现Android多文件上传

实现多文件的上传，基于标准的http来实现。

1.多文件上传MyUploader类的实现：

/**
*
* 同步上传多个文件
* 基于标准的http实现，需要在非UI线程中调用，以免阻塞UI。
*
*/
public class MyUploader {
private static final String TAG = "MyUploader";

// ////////////////////同步上传多个文件/////////
 /**
  * 同步上传File
  *
  * @param Url
  * @param fullFileName
  *   : 全路径，ex. /sdcard/f/yh.jpg
  * @param fileName
  *   : file name, ex. yh.jpg
  * @return 服务器的响应结果(字符串形式)
  */
 public String MyUploadMultiFileSync(String Url,
   List<String> fileList, Map<String, String> params) {
  String reulstCode = "";
  String end = "\r\n";
  String twoHyphens = "--";
  String boundary = "--------boundary";

try {
   URL url = new URL(actionUrl);
   HttpURLConnection con = (HttpURLConnection) url.openConnection();
   // 允许Input、Output，不使用Cache
   con.setDoInput(true);
   con.setDoOutput(true);
   con.setUseCaches(false);
   // 设置传送的method=POST
   con.setRequestMethod("POST");
   // setRequestProperty
   con.setRequestProperty("Connection", "Keep-Alive");
   con.setRequestProperty("Charset", "UTF-8");
   // con.setRequestProperty("Content-Type",
   // "application/x-www-form-urlencoded");
   con.setRequestProperty("Content-Type",
     "multipart/form-data;boundary=" + boundary);

StringBuffer s = new StringBuffer();
   // 设置DataOutputStream
   DataOutputStream dos = new DataOutputStream(con.getOutputStream());

for (int i = 0; i < fileList.size(); i++) {

String filePath = fileList.get(i);

int endFileIndex = filePath.lastIndexOf("/");
    String fileName = filePath.substring(endFileIndex + 1);
    Log.i(TAG, "filename= " + fileName);
    // set 头部
    StringBuilder sb = new StringBuilder();

sb.append(twoHyphens);
    sb.append(boundary);
    sb.append(end);
    sb.append("Content-Disposition: form-data; ");
    sb.append("name=" + "\"" + "upload_file" +i + "\"");
    sb.append(";filename=");
    sb.append("\"" + fileName + "\"");
    sb.append(end);

sb.append("Content-Type: ");
    sb.append("image/jpeg");
    sb.append(end);
    sb.append(end);

// 1. write sb
    dos.writeBytes(sb.toString());

// 取得文件的FileInputStream
    FileInputStream fis = new FileInputStream(filePath);
    // 设置每次写入1024bytes
    int bufferSize = 1024;
    byte[] buffer = new byte[bufferSize];

int length = -1;
    // 从文件读取数据至缓冲区
    while ((length = fis.read(buffer)) != -1) {
     dos.write(buffer, 0, length);
    }
    dos.writeBytes(end);
    fis.close();

dos.writeBytes(end);
    dos.writeBytes(end);

//dos.writeBytes(end);
    //dos.flush();
    // close streams
    //fis.close();
   }

// set 尾部
   StringBuilder sb2 = new StringBuilder();

if (params != null && !params.isEmpty()) {
    for (String key : params.keySet()) {
     String value = params.get(key);
     sb2.append(twoHyphens);
     sb2.append(boundary);
     sb2.append(end);
     sb2.append("Content-Disposition: form-data; ");
     sb2.append("name=" + "\"");
     sb2.append(key + "\"");
     sb2.append(end);
     sb2.append(end);
     sb2.append(value);
     sb2.append(end);
    }
   }
   sb2.append(twoHyphens + boundary + end);
   dos.writeBytes(sb2.toString());
   dos.flush();
   Log.i(TAG, "sb2:" + sb2.toString());

// 取得Response内容
   InputStream is = con.getInputStream();
   int ch;
   StringBuffer b = new StringBuffer();
   while ((ch = is.read()) != -1) {
    b.append((char) ch);
   }
   reulstCode = b.toString().trim();
   // 关闭
   dos.close();
  } catch (IOException e) {
   Log.i(TAG, "IOException: " + e);
   e.printStackTrace();
  }

return reulstCode;
 }
}

2. 调用方法：

由于MyUploader的MyUploadMultiFileSync本身是同步的函数请求，所以，这个函数需要在非UI线程中执行。本例采用Thread+Handler的方式来进行说明。
下面是activity的主要代码,功能是将cache目录中的的jpg文件上传到指定的服务器：

public void uploadThreadTest() {
 new Thread(new Runnable() {
  @Override
  public void run() {

try {
    upload();
   } catch (Exception e) {
    e.printStackTrace();
   }
  }

}).start();

}

private void upload() {
 String url = "https://httpbin.org/post";
 List<String> fileList = getCacheFiles();

if (fileList == null) {
  myHandler.sendEmptyMessage(-1);
 }else {
  MyUploader myUpload = new MyUploader();
  //同步请求，直接返回结果，根据结果来判断是否成功。
  String reulstCode = myUpload.MyUploadMultiFileSync(url, fileList, null);
  Log.i(TAG, "upload reulstCode: " + reulstCode);
  myHandler.sendEmptyMessage(0);

}
}

private List<String> getCacheFiles() {
 List<String> fileList = new ArrayList<String>();
 File catchPath = mContext.getCacheDir();

if (catchPath!=null && catchPath.isDirectory()) {

File[] files = catchPath.listFiles();
  if (files == null || files.length<1) {
   return null;
  }
  for (int i = 0; i < files.length; i++) {
   if (files[i].isFile() && files[i].getAbsolutePath().endsWith(".jpg")) {
    fileList.add(files[i].getAbsolutePath());
   }

}
  return fileList;

}
 return null;

}
////////////handler/////
private Handler myHandler = new Handler() {
 @Override
 public void handleMessage(Message msg) {
  Log.i(TAG,"handleMessage msg===" + msg);
  if (msg.what == -1) {
   Toast.makeText(mContext, "not find file!", Toast.LENGTH_LONG).show();
   return;
  }else {
   Toast.makeText(mContext, "upload success!", Toast.LENGTH_LONG).show();
  }

}

};

3 项目demo代码地址：https://github.com/ranke/HttpAsyncTest