http - Java servlet shared collection -

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• how servlets work? instantiation, sessions, shared variables , multithreading 6 answers

please me. there way how can use collection shared between servlet instances?

i know can save string in httprequestcontext how can store collection? know use database i'd prefer store in memory

public class servlet extends httpservlet {      public void doget(httpservletrequest request,                     httpservletresponse response)             throws servletexception, ioexception   {       context.setattribute("somevalue", "avalue");       //  want use collection here   }  } 

thank answers.

you can store in session - quite common. in public static collection in external class - sake of example util.mycollection. careful though, servlets should thread-safe , stateless, latter can considered anti-patttern - can lot of trouble doing this.