java - RESTful web service life cycle is *always* per request? -

-

in beginning java ee 7 antonio goncalves written:

in section writing restful web services -> life cycle , callback:

thus, life cycle of restful web service per request service not have worry concurrency , can use instance variables safely.

yet couple lines later writes:

remember restful web service can annotated @stateless or @singleton benefit services of session beans.

so it? lifecycle per request or can session too?

in addition that, if life cycle session, how handle @context annotation when injecting httpheaders attribute? headers vary during session, attribute updated after each request?

according jax-rs specification, every implementation (like jersey) must support per-request behaviour:

3.1.1 lifecycle , environment

by default new resource class instance created each request resource. first constructor (see section 3.1.2) called, requested dependencies injected (see section 3.2), appropriate method (see section 3.3) invoked , object made available garbage collection.

an implementation may offer other resource class lifecycles, mechanisms specifying these outside scope of specification. e.g. implementation based on inversion-of-control framework may support of lifecycle options provided framework.

this means if resource class not additionally annotated, per-request. 1 well-known exception spring beans: if rest resource spring bean, spring specifies lifecycle of class. same ejbs (@singleton)


Comments

Post a Comment

Popular posts from this blog

How to access named pipes using JavaScript in Firefox add-on? -

-
i'm trying access named pipe in firefox add-on. code, based on solution 2 this codeproject question, is: var file = components.classes["@mozilla.org/file/local;1"].createinstance(components.interfaces.nsilocalfile); file.initwithpath("\\\\.\\pipe\\test"); var text = "some text written"; var writer = components.classes["@mozilla.org/network/file-output-stream;1"].createinstance(components.interfaces.nsifileoutputstream); // open file read/write access, , create if not exist. writer.init (file, 0x04 | 0x08, -1, 0); writer.write (text, text.length); writer.flush (); writer.close (); when run firefox scratchpad, get: /* exception: component returned failure code: 0x80520012 (ns_error_file_not_found) [nsifileoutputstream.init] @6 */ line 6 line call writer.init. i've played passing different flags writer.init, no luck. i'm able write normal file path code, not named pipe path. i've been searching more information of da...
Read more

multithreading - OPAL (Open Phone Abstraction Library) Transport not terminated when reattaching thread? -

-
i in process of writing application using opal makes h323 calls. have looked online number of working examples , have managed put resembles should like, @ present able call external ip via application when accept call craps out , dies. leaving me with: 0:12.949 setupcall:8752 sert.cxx(259) assertion fail: transport not terminated when reattaching thread , file d:\voip\software\opal\src\opal\transports.cxx, line 1021 passertfunc(0xde3f88, 0xffffffffd228226f, 0, 0) + 0x82 passertfunc(0x10d6e5f8, 0x3fd, 0, 0x10d6eb98) + 0x15b opaltransport::attachthread(0xde5870, 0xffffffffd22fc76b, 0, 0) + 0x96 h323connection::setupconnection(0xffffffffd22fc713, 0, 0, 0xde6ea8) + 0x196 asynchcallsetup(0x10d3572c, 0, 0, 0xdd0108) + 0x7c pthread1arg<psafeptr<opalconnection,psafeptrbase> >::main(0xffffffffd2282faf from have deduced, perhaps incorrectly if there thread lock issue caused (possibly arising fact application sending expected h323 call, throwing in c...
Read more

node.js - req param returns an empty array -

-
i using node.js , mongodb geolocation app , req param returns empty array exports.findpressure = function(req, res) { var queryobject = req.param('q'); console.log(queryobject); db.collection('pressure', function(err, collection) { collection.find( { loc: { $near :[ req.param('q') ] , $maxdistance : 5 }},{"value" : 1, _id : 0}) .sort({_id : -1}).limit(1).toarray(function(err, items) { res.send(items); }); }); }; the longitude , latitude values displayed in console listening on port 3000... connected 'weather' database 8.9068256,52.019347499999995 /pressure?q=8.9068256,52.019347499999995 200 27ms - 2b the url follows http://localhost:3000/pressure?q=8.9068256,52.019347499999995 if use values 8.9068256,52.019347499999995 getting value database if use req.param('q') returning empty array you seem passing values part of query string. req.query.q should contain comma-s...
Read more