osgi - guice - select different providers while running -


i want change provider i'm using @ runtime without having stop jvm. example, isn't i'm trying do, idea same: say, want switch amazon s3 google cloud storage in middle of running application.

is can within guice?

i have have jars available @ runtime , configure modules @ startup. then, later once application started, i'd have use provider can determine instance inject @ startup , later on when changes.

or, better restart application after updating configuration , system proceed configuration , if needs change, application again need restarted.

would osgi here?

you don't need extra: guice can out-of-the-box. but... you'll have use providers instead of direct instance.

in module

bind(cloud.class)   .annotatedwith(names.named("google"))   .to(googlecloud.class); bind(cloud.class)   .annotatedwith(names.named("amazon"))   .to(amazoncloud.class); bind(cloud.class)   .toprovider(switchingcloudprovider.class);

somewhere

class switchingcloudprovider implements provider<cloud> {   @inject @named("google") provider<cloud> googlecloudprovider;   @inject @named("amazon") provider<cloud> amazoncloudprovider;   @inject configuration configuration;        // used switch "commander"   public cloud get() {     switch(configuration.getcloudname()) {       case "google": return googlecloudprovider.get();       case "amazon": return amazoncloudprovider.get();       default:          // whatever want, exception.     }   } }

or in provider method in module

@provides cloud providecloud(     @named("google") provider<cloud> googlecloudprovider,     @named("amazon") provider<cloud> amazoncloudprovider,     configuration configuration) {   switch(configuration.getcloudname()) {     case "google": return googlecloudprovider.get();     case "amazon": return amazoncloudprovider.get();     default:        // whatever want, exception.   } }

usage

class foo {   @inject provider<cloud> cloudprovider; // not inject cloud directly or won't changes come up.   public void bar() {     cloud cloud = cloudprovider.get();     // use cloud   } }

Comments

Post a Comment

Popular posts from this blog

Is there a better way to structure post methods in Class Based Views -

i'm using class based views in django , never specify url in ajax calls , omit action parameter in form because know these requests go through post method of class based view. notice view - profile page make many requests depending on user updating on page - post method become convoluted , if/else mess example: def post(self, request, *args, **kwargs): # handle user changing available date if request.post.get('availabledate') != none: self.updateavailabledate(request) return jsonresponse({'result':'success'}) if request.post.get('newprojectname') != none: creative_user = creativeuserprofile.objects.get(id = request.user.id) project = project.create_project(creative_user, request.post['newprojectname']) project.save() return jsonresponse({'projectid': project.id }) if request.post.get('projectimage') != none , request.files['file']: proj...
Read more

performance - Why is XCHG reg, reg a 3 micro-op instruction on modern Intel architectures? -

i'm doing micro-optimization on performance critical part of code , came across sequence of instructions (in at&t syntax): add %rax, %rbx mov %rdx, %rax mov %rbx, %rdx i thought had use case xchg allow me shave instruction , write: add %rbx, %rax xchg %rax, %rdx however, dimay found agner fog's instruction tables , xchg 3 micro-op instruction 2 cycle latency on sandy bridge, ivy bridge, broadwell, haswell , skylake. 3 whole micro-ops , 2 cycles of latency! 3 micro-ops throws off 4-1-1-1 cadence , 2 cycle latency makes worse original in best case since last 2 instructions in original might execute in parallel. now... cpu might breaking instruction micro-ops equivalent to: mov %rax, %tmp mov %rdx, %rax mov %tmp, %rdx where tmp anonymous internal register , suppose last 2 micro-ops run in parallel latency 2 cycles. given register renaming occurs on these micro-architectures, though, doesn't make sense me done way. why wouldn't register renamer ...
Read more

c# - Asp.net web api : redirect unauthorized requst to forbidden page -

im trying redirect unauthorized request forbidden page instead i'm getting forbidden page in response body , how can fix ? here's startup class : app.createperowincontext(storecontext.create); app.createperowincontext<applicationusermanager>(applicationusermanager.create); app.createperowincontext<applicationsigninmanager>(applicationsigninmanager.create); app.usecookieauthentication(new cookieauthenticationoptions { authenticationtype = defaultauthenticationtypes.applicationcookie, expiretimespan = timespan.fromdays(30), }); app.useexternalsignincookie(defaultauthenticationtypes.externalcookie); app.usetwofactorsignincookie(defaultauthenticationtypes.twofactorcookie, timespan.fromminutes(5)); app.usetwofactorrememberbrowsercookie(defaultauthenticationtypes.twofactorrememberbrowsercookie); the method im trying reach : [httpget] [authorize(roles = "admin")] public string getcurrentusername() { return userman...
Read more