我使用以下代码从blobstore获取blob引用
//Connect with the ImgUpload servlet to get UploadStrurl
public class getUrl implements Runnable
{
HttpGet httpGet=new HttpGet();
org.apache.http.HttpResponse response=null;
@Override
public void run() {
try {
HttpClient httpClient = new DefaultHttpClient();
httpGet = new HttpGet(url_get);
response = httpClient.execute(httpGet);
HttpEntity entity = response.getEntity();
responseBlobUrlString=EntityUtils.toString(entity);
} catch (ClientProtocolException e) {
Log.e(TAG, "ClientProtocolException", e);
} catch (ParseException e) {
Log.e(TAG, "ParseException", e);
} catch (IOException e) {
Log.e(TAG, "IOException", e);
}
}
以上代码经过测试且运行正常。 要响应的servlet代码：
public class TestServletServlet extends HttpServlet {
com.google.appengine.api.blobstore.BlobstoreService blobstoreService = BlobstoreServiceFactory
.getBlobstoreService();
@Override
public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
String blobUploadUrl = blobstoreService.createUploadUrl("/upload");
//new code{
resp.setStatus(HttpServletResponse.SC_OK);
resp.setContentType("text/plain");
PrintWriter out = resp.getWriter();
out.print(blobUploadUrl);
out.flush();
out.close();
}
@Override
public void doPost(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
}
}
以上代码经过测试且运行正常。 我使用以下代码发布我的图片：
public static String executeHttpPost(String url, String image_path) throws Exception {
InputStream in = null;
HttpEntity entity1=null;
MultipartEntity mpentity = new MultipartEntity();
HttpClient client = getHttpClient();
org.apache.http.HttpResponse response = null;
HttpPost request;
String responseBody = null;
String result=null;
HttpParams params = (HttpParams) new BasicHttpParams();
request = new HttpPost(url);
File file=new File(image_path);
FileBody fb=new FileBody(file);
mpentity.addPart("file", fb);
request.setEntity(mpentity);
try{
response = client.execute(request);
HttpEntity urlEntity = response.getEntity();
if (response.getEntity().getContentLength()!=0)
result=response.getEntity().toString();
else
result="0";
return result;
}
catch (Exception e) {
e.toString();
}
return result;
}
以上代码经过测试且运行正常。 来自servlet端的响应：
public void doPost(HttpServletRequest req, HttpServletResponse resp)
throws IOException {
List<BlobKey> blobs = blobstoreService.getUploads(req).get("file");
BlobKey blobKey = blobs.get(0);
ImagesService imagesService = (ImagesService) ImagesServiceFactory.getImagesService();
ServingUrlOptions servingOptions = ServingUrlOptions.Builder.withBlobKey(blobKey);
String servingUrl = ((com.google.appengine.api.images.ImagesService) imagesService).getServingUrl(servingOptions);
resp.setStatus(HttpServletResponse.SC_OK);
resp.setContentType("application/json");
JSONObject json = new JSONObject();
try {
json.put("servingUrl", servingUrl);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
json.put("blobKey", blobKey.getKeyString());
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
PrintWriter out = resp.getWriter();
out = resp.getWriter();
out.print(json.toString());
out.flush();
out.close();
}
这段代码没有按预期返回blobkey和服务url。 我通过异步任务激活HttpPost，如下所示：
class TheTask extends AsyncTask<String,String,String>
{
String response = null;
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
//error message
debuger.setText("the returned response is:"+result);
}
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
}
@Override
protected String doInBackground(String... params) {
JSONObject resultJson=null;
try {
blobKey= CustomHttpClient.executeHttpPost(params[0], photo_striped);
}
catch(Exception e)
{
blobKey="exception in geting resp";
e.printStackTrace();
}
try {
resultJson = new JSONObject(blobKey);
blobKey = resultJson.getString("blobKey");
servingUrl = resultJson.getString("servingUrl");
} catch (JSONException e) {
e.printStackTrace();
}
return blobKey;
}
}
以上代码经过测试且运行正常。 我使用下面的codelet在我的活动中执行我的异步任务：
back.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
ViewFlipper vf = (ViewFlipper) findViewById( R.id.viewFlipper );
vf.showNext();
new TheTask().execute(responseBlobUrlString);
}
});
我的web.xml是：
<?xml version="1.0" encoding="utf-8" standalone="no"?><web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.5" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<welcome-file-list>
<welcome-file>index.html</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>SystemServiceServlet</servlet-name>
<servlet-class>com.google.api.server.spi.SystemServiceServlet</servlet-class>
<init-param>
<param-name>services</param-name>
<param-value>com.alphaapps.quoteserver.QuoteEndpoint</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>SystemServiceServlet</servlet-name>
<url-pattern>/_ah/spi/*</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>uploaded</servlet-name>
<servlet-class>com.alphaapps.quoteserver.uploaded</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>uploaded</servlet-name>
<url-pattern>/upload</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>Test</servlet-name>
<servlet-class>com.alphaapps.quoteserver.TestServletServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Test</servlet-name>
<url-pattern>/test</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>Serve</servlet-name>
<servlet-class>com.alphaapps.quoteserver.Serve</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Serve</servlet-name>
<url-pattern>/serve</url-pattern>
</servlet-mapping>
</web-app>
请帮我解决这个错误。上传图片但没有得到blobstore的回复真是一件令人讨厌的事...... 当我检查响应时它没有打印任何内容，这意味着blobstore没有返回任何blobkey或任何其他值......