我遇到了在Android上传图片的问题。
我正在使用apache httpmime 4.1 lib 代码是这样的：
MultipartEntity reqEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
reqEntity.addPart("image", new FileBody(new File(AndorraApplication.getPhotosPath() + "/" + entity.getFileName()), "image/jpeg"));
resp = NetworkUtils.sendHttpRequestMultipart(EXPORT_PHOTOS_URI, reqEntity);
NetworkUtils类：
public class NetworkUtils {
public static final int REGISTRATION_TIMEOUT = 3 * 1000;
public static final int WAIT_TIMEOUT = 5 * 1000;
public static HttpResponse sendHttpRequestMultipart(String uri, MultipartEntity entity) {
HttpClient mHttpClient = new DefaultHttpClient();
final HttpParams params = mHttpClient.getParams();
HttpConnectionParams.setConnectionTimeout(params, REGISTRATION_TIMEOUT);
HttpConnectionParams.setSoTimeout(params, WAIT_TIMEOUT);
ConnManagerParams.setTimeout(params, WAIT_TIMEOUT);
HttpPost post = new HttpPost(uri);
post.addHeader(entity.getContentType());
post.setEntity(entity);
HttpResponse resp = mHttpClient.execute(post);
}
}
有时候一切正常，但有时（特别是在连接速度慢的情况下）图像上传时非常破坏。示例如下：http://pixelbirthcloud.com/574_orig.jpg
它不会抛出任何异常。上传文件的长度与原始文件的长度相同..尝试将mime类型更改为application / octet-stream或将其删除。尝试玩超时。还是一样的结果。最终用户几乎一直上传损坏的图像（虽然我设法只获得了2次的bronem图像）..图像大小最初是2.5兆，但后来我把它减少到500-700 kb。虽然没有解决问题。
没有尝试更改apache的库..也许这是问题..但就我读到网而言，没有人通过httpmime库体验这一点。
它能是什么？我现在完全迷失了:(
另一个问题是超时有时不起作用。
就像说到这一行： HttpResponse resp = mHttpClient.execute（post）; 我禁用3g连接它只需要等待17-20分钟而不是3或5秒......然后才会抛出异常。试过不同的方法。像这样：
HttpParams params = new BasicHttpParams();
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);
HttpProtocolParams.setUseExpectContinue(params, false);
HttpConnectionParams.setConnectionTimeout(params, 10000);
HttpConnectionParams.setSoTimeout(params, 10000);
ConnManagerParams.setMaxTotalConnections(params, 5);
ConnManagerParams.setTimeout(params, 30000);
SchemeRegistry registry = new SchemeRegistry();
registry.register(new Scheme("http",PlainSocketFactory.getSocketFactory(), 80));
registry.register(new Scheme("https",PlainSocketFactory.getSocketFactory(), 80));
ThreadSafeClientConnManager manager = new ThreadSafeClientConnManager(params, registry);
HttpClient httpclient = new DefaultHttpClient(manager, params);
但仍然不起作用：）
答案 0 :(得分：7)
请参阅我的图像上传器代码，它对我很有用 此类将文件上传到服务器，最后也读取XML回复。 根据您的要求过滤代码..它对我来说非常顺利
package com.classifieds;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import android.util.Log;
public class Uploader
{
private String Tag = "UPLOADER";
private String urlString ;//= "YOUR_ONLINE_PHP";
HttpURLConnection conn;
String exsistingFileName ;
private void uploadImageData(String existingFileName , String urlString)
{
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
try {
// ------------------ CLIENT REQUEST
Log.e(Tag, "Inside second Method");
FileInputStream fileInputStream = new FileInputStream(new File(
exsistingFileName));
// open a URL connection to the Servlet
URL url = new URL(urlString);
// Open a HTTP connection to the URL
conn = (HttpURLConnection) url.openConnection();
// Allow Inputs
conn.setDoInput(true);
// Allow Outputs
conn.setDoOutput(true);
// Don't use a cached copy.
conn.setUseCaches(false);
// Use a post method.
conn.setRequestMethod("POST");
conn.setRequestProperty("Connection", "Keep-Alive");
conn.setRequestProperty("Content-Type",
"multipart/form-data;boundary=" + boundary);
DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
dos.writeBytes(twoHyphens + boundary + lineEnd);
dos
.writeBytes("Content-Disposition: post-data; name=uploadedfile;filename="
+ exsistingFileName + "" + lineEnd);
dos.writeBytes(lineEnd);
Log.v(Tag, "Headers are written");
// create a buffer of maximum size
int bytesAvailable = fileInputStream.available();
int maxBufferSize = 1000;
// int bufferSize = Math.min(bytesAvailable, maxBufferSize);
byte[] buffer = new byte[bytesAvailable];
// read file and write it into form...
int bytesRead = fileInputStream.read(buffer, 0, bytesAvailable);
while (bytesRead > 0) {
dos.write(buffer, 0, bytesAvailable);
bytesAvailable = fileInputStream.available();
bytesAvailable = Math.min(bytesAvailable, maxBufferSize);
bytesRead = fileInputStream.read(buffer, 0, bytesAvailable);
}
// send multipart form data necesssary after file data...
dos.writeBytes(lineEnd);
dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
// close streams
Log.v(Tag, "File is written");
fileInputStream.close();
dos.flush();
dos.close();
} catch (MalformedURLException ex) {
Log.e(Tag, "error: " + ex.getMessage(), ex);
}
catch (IOException ioe) {
Log.e(Tag, "error: " + ioe.getMessage(), ioe);
}
SAXParserFactory spf = SAXParserFactory.newInstance();
SAXParser sp = null;
try {
sp = spf.newSAXParser();
} catch (ParserConfigurationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SAXException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// Get the XMLReader of the SAXParser we created.
XMLReader xr = null;
try {
xr = sp.getXMLReader();
} catch (SAXException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// Create a new ContentHandler and apply it to the XML-Reader
MyExampleHandler1 myExampleHandler = new MyExampleHandler1();
xr.setContentHandler(myExampleHandler);
// Parse the xml-data from our URL.
try {
xr.parse(new InputSource(conn.getInputStream()));
//xr.parse(new InputSource(new java.io.FileInputStream(new java.io.File("login.xml"))));
} catch (MalformedURLException e) {
Log.d("Net Disconnected", "NetDisconeeted");
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
Log.d("Net Disconnected", "NetDisconeeted");
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SAXException e) {
Log.d("Net Disconnected", "NetDisconeeted");
// TODO Auto-generated catch block
e.printStackTrace();
}
// Parsing has finished.
}
public Uploader(String existingFileName, boolean isImageUploading , String urlString ) {
this.exsistingFileName = existingFileName;
this.urlString = urlString;
}
class MyExampleHandler1 extends DefaultHandler
{
// ===========================================================
// Methods
// ===========================================================
@Override
public void startDocument() throws SAXException {
}
@Override
public void endDocument() throws SAXException {
// Nothing to do
}
@Override
public void startElement(String namespaceURI, String localName,
String qName, Attributes atts) throws SAXException {
}
/** Gets be called on closing tags like:
* </tag> */
@Override
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
}
/** Gets be called on the following structure:
* <tag>characters</tag> */
@Override
public void characters(char ch[], int start, int length) {
}
}
}
答案 1 :(得分：4)
我80％的上传文件都存在同样的损坏问题。虽然模拟器没有上传失败。损坏的文件比原始文件大1k。然后我将输出流的缓冲区设置为1个字节，它开始工作没有问题。最后我让它为8个字节，并没有更多的腐败问题。一个约80或50的缓冲区，我记不住了，也失败了。不明白问题是什么，但我很高兴它正在以这种方式工作。这个页面非常鼓舞人心。
答案 2 :(得分：1)
确定。花了2天时间测试这个问题并发现以下内容：
在android上使用tcpdump时，数据没有损坏，但是tcp数据包大小为1516，这很奇怪，导致正常的以太网数据包大小为1500，而且超过1516的数据都太大了。
我手动将MTU改为576（我相信它是ppp的标准，实际上是3G）并且它完美无缺！正常上传150张图片中的150张！
这并不能解决实际问题，但是，因为我无法在非根设备上更改mtu，而且每次重启设备时（或每次调出界面时都必须更改）不确定，因为找不到通过ifconfig获取MTU值的方法）。但至少我知道问题出在哪里 将http块大小设置为较小的值（尝试300字节）并没有影响它（我相信这是因为http标头本身太大了）...所以...所以没有什么=）
会尝试将它发布到谷歌上的android-developer组，但他们的节制太慢了......我们会看到......