download + onlyRetrieveFromCache block

[hackerwgf]

download image like this:

GlideApp.with(context)
.download(imageUrl)
.submit();

and load it onlyRetrieveFromCache at the same time:

new Thread(new Runnable() {
    @Override
    public void run() {
        try{
            GlideApp.with(context)
            .download(imageUrl)
            .onlyRetrieveFromCache(true)
            .submit()
            .get();
         }catch (Exception e){
             e.printStackTrace();
         }
    }
}).start();

then .get() will block

[sjudd]

.get() will block, yes. Is that what you were asking?

[hackerwgf]

So...why? I think .onlyRetrieveFromCache(true), it means that if no cache file here, then throw exception or just return null something else.
I apologize for my bad English

[sjudd]

You still need to do I/O to check the disk cache and decode the image if it's present.

[hackerwgf]

I know it need time to do I/O stuff, maybe I did not express my meaning clearly.
In my situation, .get() will block by downloading the same imageUrl, not decoding or checking file.

A=.download(imageUrl).submit()
B=.download(imageUrl).onlyRetrieveFromCache(true).submit().get() in new thread
current situation:
start A >>>>>>downloading>>>>>>downloaded
start B >>>>>>blocking>>>>>>>>>got file

my expectation:
start A >>>>>>downloading>>>>>>downloaded
start B >>>>>>return error

[sjudd]

Ah, then start with: http://bumptech.github.io/glide/doc/debugging.html#unexpected-cache-misses. The Engine logs will tell you why there is/isn't a cache miss.

[hackerwgf]

The log is "Added to existing load ...", that's why .get() blocked.
Maybe I should take the time to read source code for In-depth understanding.
.onlyRetrieveFromCache(true) makes me completely confused, especially the word ONLY.
So now look, is there a way to check cache file without blocking caused by existing load, or check a request status with url ?

[stale]

This issue has been automatically marked as stale because it has not had activity in the last seven days. It will be closed if no further activity occurs within the next seven days. Thank you for your contributions.

[Caij]

load image from server, when the task is not completed, load same url request image only from cache, why second request need block wait first request complete(file down completed)? i think second request need return null.

the source code from:

EngineKey key = keyFactory.buildKey(model, signature, width, height, transformations,
resourceClass, transcodeClass, options);
EngineJob<?> current = jobs.get(key);
if (current != null) {
current.addCallback(cb);
if (Log.isLoggable(TAG, Log.VERBOSE)) {
logWithTimeAndKey("Added to existing load", startTime, key);
}
return new LoadStatus(cb, current);
}