1, project research
Because the need to study the issue breakpoint upload. Looking for a long finally found a good project.
In GoogleCode above, the code to get down to super inconvenient, or configure the hosts go, re-upload the code to github above.
https://github.com/freewebsys/java-large-file-uploader-demo
effect:
Upload, display progress, time and percentage.
Click [Pause] to pause, click [Resume] to continue.
2, code analysis
The original project:
https://code.google.com/p/java-large-file-uploader/
This project was last updated in 2012, the project was packaged using the easiest way to achieve a breakpoint upload the http.
Because there are html5 library to read the file split file, so it can support the breakpoint upload, so this can only be displayed in the browser html5 support of the above.
Meanwhile, while a checksum for the file blocks in cr32 and js java, to ensure that the correct data upload.
Code using the latest servlet api 3.0 using asynchronous execution, monitoring and other methods.
Upload class UploadServlet
@Component("javaLargeFileUploaderServlet")
@WebServlet(name = "javaLargeFileUploaderServlet", urlPatterns = { "/javaLargeFileUploaderServlet" })
public class UploadServlet extends HttpRequestHandlerServlet
implements HttpRequestHandler {
private static final Logger log = LoggerFactory.getLogger(UploadServlet.class);
@Autowired
UploadProcessor uploadProcessor;
@Autowired
FileUploaderHelper fileUploaderHelper;
@Autowired
ExceptionCodeMappingHelper exceptionCodeMappingHelper;
@Autowired
Authorizer authorizer;
@Autowired
StaticStateIdentifierManager staticStateIdentifierManager;
@Override
public void handleRequest(HttpServletRequest request, HttpServletResponse response)
throws IOException {
log.trace("Handling request");
Serializable jsonObject = null;
try {
// extract the action from the request
UploadServletAction actionByParameterName =
UploadServletAction.valueOf(fileUploaderHelper.getParameterValue(request, UploadServletParameter.action));
// check authorization
checkAuthorization(request, actionByParameterName);
// then process the asked action
jsonObject = processAction(actionByParameterName, request);
// if something has to be written to the response
if (jsonObject != null) {
fileUploaderHelper.writeToResponse(jsonObject, response);
}
}
// If exception, write it
catch (Exception e) {
exceptionCodeMappingHelper.processException(e, response);
}
}
private void checkAuthorization(HttpServletRequest request, UploadServletAction actionByParameterName)
throws MissingParameterException, AuthorizationException {
// check authorization
// if its not get progress (because we do not really care about authorization for get
// progress and it uses an array of file ids)
if (!actionByParameterName.equals(UploadServletAction.getProgress)) {
// extract uuid
final String fileIdFieldValue = fileUploaderHelper.getParameterValue(request, UploadServletParameter.fileId, false);
// if this is init, the identifier is the one in parameter
UUID clientOrJobId;
String parameter = fileUploaderHelper.getParameterValue(request, UploadServletParameter.clientId, false);
if (actionByParameterName.equals(UploadServletAction.getConfig) && parameter != null) {
clientOrJobId = UUID.fromString(parameter);
}
// if not, get it from manager
else {
clientOrJobId = staticStateIdentifierManager.getIdentifier();
}
// call authorizer
authorizer.getAuthorization(
request,
actionByParameterName,
clientOrJobId,
fileIdFieldValue != null ? getFileIdsFromString(fileIdFieldValue).toArray(new UUID[] {}) : null);
}
}
private Serializable processAction(UploadServletAction actionByParameterName, HttpServletRequest request)
throws Exception {
log.debug("Processing action " + actionByParameterName.name());
Serializable returnObject = null;
switch (actionByParameterName) {
case getConfig:
String parameterValue = fileUploaderHelper.getParameterValue(request, UploadServletParameter.clientId, false);
returnObject =
uploadProcessor.getConfig(
parameterValue != null ? UUID.fromString(parameterValue) : null);
break;
case verifyCrcOfUncheckedPart:
returnObject = verifyCrcOfUncheckedPart(request);
break;
case prepareUpload:
returnObject = prepareUpload(request);
break;
case clearFile:
uploadProcessor.clearFile(UUID.fromString(fileUploaderHelper.getParameterValue(request, UploadServletParameter.fileId)));
break;
case clearAll:
uploadProcessor.clearAll();
break;
case pause file:
List<UUID> uuids = getFileIdsFromString(fileUploaderHelper.getParameterValue(request, UploadServletParameter.fileId));
uploadProcessor.pauseFile (uuids);
break;
case resumeFile:
returnObject =
uploadProcessor.resumeFile(UUID.fromString(fileUploaderHelper.getParameterValue(request, UploadServletParameter.fileId)));
break;
case setRate:
uploadProcessor.setUploadRate(UUID.fromString(fileUploaderHelper.getParameterValue(request, UploadServletParameter.fileId)),
Long.valueOf(fileUploaderHelper.getParameterValue(request, UploadServletParameter.rate)));
break;
case getProgress:
returnObject = getProgress(request);
break;
}
return returnObject;
}
List<UUID> getFileIdsFromString(String fileIds) {
String[] splittedFileIds = fileIds.split(",");
List<UUID> uuids = Lists.newArrayList();
for (int i = 0; i < splittedFileIds.length; i++) {
uuids.add(UUID.fromString(splittedFileIds[i]));
}
return uuids;
}
private Serializable getProgress(HttpServletRequest request)
throws MissingParameterException {
Serializable returnObject;
String[] ids =
New Gson ()
.fromJson(fileUploaderHelper.getParameterValue(request, UploadServletParameter.fileId), String[].class);
Collection<UUID> uuids = Collections2.transform(Arrays.asList(ids), new Function<String, UUID>() {
@Override
public UUID apply(String input) {
return UUID.fromString(input);
}
});
returnObject = Maps.newHashMap();
for (UUID fileId : uuids) {
try {
ProgressJson progress = uploadProcessor.getProgress(fileId);
((HashMap<String, ProgressJson>) returnObject).put(fileId.toString(), progress);
}
catch (FileNotFoundException e) {
log.debug("No progress will be retrieved for " + fileId + " because " + e.getMessage());
}
}
return returnObject;
}
private Serializable prepareUpload(HttpServletRequest request)
throws MissingParameterException, IOException {
// extract file information
PrepareUploadJson [] = fromJson
New Gson ()
.fromJson(fileUploaderHelper.getParameterValue(request, UploadServletParameter.newFiles), PrepareUploadJson[].class);
// prepare them
final HashMap<String, UUID> prepareUpload = uploadProcessor.prepareUpload(fromJson);
// return them
return Maps.newHashMap(Maps.transformValues(prepareUpload, new Function<UUID, String>() {
public String apply(UUID input) {
return input.toString();
};
}));
}
private Boolean verifyCrcOfUncheckedPart(HttpServletRequest request)
throws IOException, MissingParameterException, FileCorruptedException, FileStillProcessingException {
UUID fileId = UUID.fromString(fileUploaderHelper.getParameterValue(request, UploadServletParameter.fileId));
try {
uploadProcessor.verifyCrcOfUncheckedPart(fileId,
fileUploaderHelper.getParameterValue(request, UploadServletParameter.crc));
}
catch (InvalidCrcException e) {
// no need to log this exception, a fallback behaviour is defined in the
// throwing method.
// but we need to return something!
return Boolean.FALSE;
}
return Boolean.TRUE;
}
}
Asynchronous upload UploadServletAsync
@Component("javaLargeFileUploaderAsyncServlet")
@WebServlet(name = "javaLargeFileUploaderAsyncServlet", urlPatterns = { "/javaLargeFileUploaderAsyncServlet" }, asyncSupported = true)
public class UploadServletAsync extends HttpRequestHandlerServlet
implements HttpRequestHandler {
private static final Logger log = LoggerFactory.getLogger(UploadServletAsync.class);
@Autowired
ExceptionCodeMappingHelper exceptionCodeMappingHelper;
@Autowired
UploadServletAsyncProcessor uploadServletAsyncProcessor;
@Autowired
StaticStateIdentifierManager staticStateIdentifierManager;
@Autowired
StaticStateManager<StaticStatePersistedOnFileSystemEntity> staticStateManager;
@Autowired
FileUploaderHelper fileUploaderHelper;
@Autowired
Authorizer authorizer;
/**
* Maximum time that a streaming request can take.<br>
*/
private long taskTimeOut = DateUtils.MILLIS_PER_HOUR;
@Override
public void handleRequest(final HttpServletRequest request, final HttpServletResponse response)
throws ServletException, IOException {
// process the request
try {
//check if uploads are allowed
if (!uploadServletAsyncProcessor.isEnabled()) {
throw new UploadIsCurrentlyDisabled();
}
// extract stuff from request
final FileUploadConfiguration process = fileUploaderHelper.extractFileUploadConfiguration(request);
log.debug("received upload request with config: "+process);
// verify authorization
final UUID clientId = staticStateIdentifierManager.getIdentifier();
authorizer.getAuthorization(request, UploadServletAction.upload, clientId, process.getFileId());
//check if that file is not paused
if (uploadServletAsyncProcessor.isFilePaused(process.getFileId())) {
log.debug("file "+process.getFileId()+" is paused, ignoring async request.");
return;
}
// get the model
StaticFileState fileState = staticStateManager.getEntityIfPresent().getFileStates().get(process.getFileId());
if (fileState == null) {
throw new FileNotFoundException("File with id " + process.getFileId() + " not found");
}
// process the request asynchronously
final AsyncContext asyncContext = request.startAsync();
asyncContext.setTimeout(taskTimeOut);
// add a listener to clear bucket and close inputstream when process is complete or
// with
// error
asyncContext.addListener(new UploadServletAsyncListenerAdapter(process.getFileId()) {
@Override
void clean() {
log.debug("request " + request + " completed.");
// we do not need to clear the inputstream here.
// and tell processor to clean its shit!
uploadServletAsyncProcessor.clean(clientId, process.getFileId());
}
});
// then process
uploadServletAsyncProcessor.process(fileState, process.getFileId(), process.getCrc(), process.getInputStream(),
new WriteChunkCompletionListener() {
@Override
public void success() {
asyncContext.complete();
}
@Override
public void error(Exception exception) {
// handles a stream ended unexpectedly , it just means the user has
// stopped the
// stream
if (exception.getMessage() != null) {
if (exception.getMessage().equals("Stream ended unexpectedly")) {
log.warn("User has stopped streaming for file " + process.getFileId());
}
else if (exception.getMessage().equals("User cancellation")) {
log.warn("User has cancelled streaming for file id " + process.getFileId());
// do nothing
}
else {
exceptionCodeMappingHelper.processException(exception, response);
}
}
else {
exceptionCodeMappingHelper.processException(exception, response);
}
asyncContext.complete();
}
});
}
catch (Exception e) {
exceptionCodeMappingHelper.processException(e, response);
}
}
}
3, a flowchart of the request:
The main idea is to file segmentation and block the upload.
Detailed reference information online search "up6 large file upload control."
Welcome to the group to discuss: 374 992 201