Java 上载带有DataOutputStream的文件不会';我看不出真正的进步
我正在使用DataOutputStream将一个文件从android上传到我的Web服务器,代码如下:Java 上载带有DataOutputStream的文件不会';我看不出真正的进步,java,android,http,stream,dataoutputstream,Java,Android,Http,Stream,Dataoutputstream,我正在使用DataOutputStream将一个文件从android上传到我的Web服务器,代码如下: public class SnapshotUploadTask extends AsyncTask<Object, Integer, Void> { private final File file; private final ProgressDialog progressDialog; private final Activity activity;
public class SnapshotUploadTask extends AsyncTask<Object, Integer, Void> {
private final File file;
private final ProgressDialog progressDialog;
private final Activity activity;
public SnapshotUploadTask(File file, ProgressDialog progressDialog, Activity activity) {
this.progressDialog = progressDialog;
this.file = file;
this.activity = activity;
}
@Override
protected void onPreExecute() {
progressDialog.setProgress(0);
}
@Override
protected Void doInBackground(Object... arg0) {
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
int bytesRead;
int bytesAvailable;
int bufferSize;
byte[] buffer;
int maxBufferSize = 1 * 512;
try {
FileInputStream fileInputStream = new FileInputStream(file);
URL url = new URL("http://bla.bla.bla/upload");
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.setDoOutput(true);
connection.setUseCaches(false);
connection.setRequestMethod("POST");
connection.setRequestProperty("Connection", "Keep-Alive");
connection.setRequestProperty("ENCTYPE", "multipart/form-data");
connection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
connection.setRequestProperty("uploaded_file", file.getName());
DataOutputStream dataOutputStream = new DataOutputStream(connection.getOutputStream());
dataOutputStream.writeBytes(twoHyphens + boundary + lineEnd);
dataOutputStream.writeBytes("Content-Disposition: form-data; name=\"uploaded_file\";filename=\"" + file.getName() + "\"" + lineEnd);
dataOutputStream.writeBytes(lineEnd);
bytesAvailable = fileInputStream.available();
final int hundredPercent = bytesAvailable;
progressDialog.setMax(hundredPercent);
bufferSize = Math.min(bytesAvailable, maxBufferSize);
buffer = new byte[bufferSize];
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
while (bytesRead > 0) {
dataOutputStream.write(buffer, 0, bufferSize);
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
final int restBytes = bytesAvailable;
final int uploadedBytes = hundredPercent - restBytes;
activity.runOnUiThread(new Runnable() {
@Override
public void run() {
progressDialog.setProgress((int) uploadedBytes);
if (restBytes <= 0) {
progressDialog.setMessage(activity.getString(R.string.camera_uploading_done));
}
}
});
}
dataOutputStream.writeBytes(lineEnd);
dataOutputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
int serverResponseCode = connection.getResponseCode();
String serverResponseMessage = connection.getResponseMessage();
if (serverResponseCode == 200) {
progressDialog.dismiss();
}
fileInputStream.close();
dataOutputStream.flush();
dataOutputStream.close();
} catch (Exception e) {
progressDialog.dismiss();
}
return null;
}
@Override
protected void onPostExecute(Void result) {
progressDialog.dismiss();
}
}
公共类SnapshotUploadTask扩展了AsyncTask{
私人最终文件;
私人最终进度对话;
私人最终活动;
公共快照上载任务(文件文件、进度对话框、活动){
this.progressDialog=progressDialog;
this.file=文件;
这个。活动=活动;
}
@凌驾
受保护的void onPreExecute(){
progressDialog.setProgress(0);
}
@凌驾
受保护的Void doInBackground(对象…arg0){
字符串lineEnd=“\r\n”;
字符串双连字符=“--”;
字符串边界=“*******”;
int字节读取;
int字节可用;
int缓冲区大小;
字节[]缓冲区;
int maxBufferSize=1*512;
试一试{
FileInputStream FileInputStream=新的FileInputStream(文件);
URL=新URL(“http://bla.bla.bla/upload");
HttpURLConnection connection=(HttpURLConnection)url.openConnection();
connection.setDoInput(true);
connection.setDoOutput(真);
connection.setUseCaches(false);
connection.setRequestMethod(“POST”);
setRequestProperty(“连接”,“保持活动”);
connection.setRequestProperty(“ENCTYPE”、“多部分/表单数据”);
connection.setRequestProperty(“内容类型”、“多部分/表单数据;边界=“+boundary”);
setRequestProperty(“上传的_文件”,file.getName());
DataOutputStream DataOutputStream=新的DataOutputStream(connection.getOutputStream());
dataOutputStream.writeBytes(两个连字符+边界+lineEnd);
dataOutputStream.writeBytes(“内容处置:表单数据;名称=\”上传的文件\“;文件名=\”+文件。getName()+“\”+行结束);
dataOutputStream.writeBytes(lineEnd);
bytesAvailable=fileInputStream.available();
最终整数百分之一百=字节可用;
progressDialog.setMax(百分之一百);
bufferSize=Math.min(字节可用,maxBufferSize);
buffer=新字节[bufferSize];
bytesRead=fileInputStream.read(缓冲区,0,缓冲区大小);
而(字节读取>0){
写入(缓冲区,0,缓冲区大小);
bytesAvailable=fileInputStream.available();
bufferSize=Math.min(字节可用,maxBufferSize);
bytesRead=fileInputStream.read(缓冲区,0,缓冲区大小);
final int restBytes=字节可用;
final int uploadedBytes=hundredPercent-restBytes;
activity.runOnUiThread(新的Runnable(){
@凌驾
公开募捐{
setProgressDialog.setProgress((int)uploadedBytes);
if(restBytes您需要知道,HttpURLConnection
缓冲所有输出,除非您设置了固定长度或分块传输模式,您当然应该这样做,而不是自己实现。这样做是为了能够准确地设置内容长度头。如果您使用其中一种传输模式,则没有缓冲
注意:您误用了available()
:请参阅Javadoc;在大多数情况下,您编写的都是垃圾邮件:
dataOutputStream.write(buffer, 0, bufferSize);
应该是
dataOutputStream.write(buffer, 0, bytesRead);
您也不需要在读取循环中摆弄available()
。类似这样的内容就足够了:
long total = 0;
int maxBufferSize = 8192; // at least. 512 is far too small.
while ((bytesRead = fileInputStream.read(buffer, 0, bufferSize)) > 0) {
dataOutputStream.write(buffer, 0, bytesRead);
total += bytesRead;
final long uploadedBytes = total;
activity.runOnUiThread(new Runnable() {
@Override
public void run() {
progressDialog.setProgress(uploadedBytes);
}
});
}
}
// at this point we are at end of stream
activity.runOnUiThread(new Runnable() {
@Override
public void run() {
progressDialog.setMessage(activity.getString(R.string.camera_uploading_done));
}
}
E&OE