问题
I have a @JavaScript annotation in my application to load a .js file from the classpath.
Now I've made an update to the file and redeployed (locally), but I always get the old version back. I've tried reloading everything (ctrl+R, ctrl+F5) but that doesn't work and also I wouldn't want the users to have to do that.
A trick I used in the past (without Vaadin) was to append a request parameter with the version (e.g. ?version=1) and update that so that the URL changes. But apparently that isn't allowed for the @JavaScript annotation (Vaadin doesn't even try to load the file).
回答1:
I have overcome this by utilizing the resourceCacheTime parameter of the Vaadin servlet configuration:
@VaadinServletConfiguration(ui = MyUI.class, resourceCacheTime = 0)
Although it has its limitation as described in my answer to another question here.
回答2:
This is browser feature to localy cache JS files, nothing to do with Vaadin.
As you figure it out yourself: If you want to make sure users have latest version of JS file, you should rename JS file name to: script_buildNumber.js.
回答3:
Use the Chrome's incognito feature (and not use it when visiting spicy/unpleasant websites).
Just open your browser in Incognito mode https://support.google.com/chrome/answer/95464?hl=en and the browser will cache nothing.
Other browsers have this feature as well (Opera, IE, Firefox, Safari).
回答4:
As I noted in my comment on the question on January 12th, renaming the file worked. This seems to be currently the only way, although it's far from ideal.
来源：https://stackoverflow.com/questions/27907327/vaadin-javascript-clear-cache-for-updated-js-file