java - Implementing Factory Method Pattern using Spring -

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i want understand how following factory method pattern can implemented using spring.

here code without using spring 

interface fileparser {       void parse() }     class xmlfileparser implements fileparser {      void parse() {      } }  class pipefileparser implements fileparser {      void parse() {      } }  class fileparserfactory {       fileparser getparserinstance(string filetype) {      if("xml".equals(filetype)               return new xmlfileparer();             else                return new pipefileparser();   } }  class activityhandler() {       void handle(string filetype) {      fileparser fileparer = fileparserfactory.getparerinstance(filetype);      fileparser.parse();   } }

thanks in advance.

i create bean fileparserfactory repsonsible returning new parsers. additionally factory bean have map (filetype => parser) , default parser

public class fileparserfactory {   private map<string, fileparser> fileparsers;  private fileparser defaultparser;   fileparser getparserinstance(string filetype) {  if(fileparsers.containskey(filetype))           return fileparsers.get(filetype);         else            return defaultparser; } public void setparsers(map<string, fileparser> parsers) {    filepaarsers = parsers; }   public void setdefaultparser(fileparser parser) {    defaultparser = parser; } }

and in code:

@inject fileparserfactory factory;

...

factory.getparser(filetype);

i assume parsers may reused , thread safe.

this solution more generic , may extended if necessarry


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