Spring 3 -- NullPointerException from JDBCTemplate.getQueryForMap() -


i running custom tag in spring jsp. getting following error message.

java.lang.nullpointerexception     com.dao.poll1dao.getvotes(poll1dao.java:27)     com.tags.poll1tag.dotag(poll1tag.java:23)     org.apache.jsp.web_002dinf.pages.pollpage_jsp._jspx_meth_mytag1_005fpoll1_005f0(pollpage_jsp.java:602)     org.apache.jsp.web_002dinf.pages.pollpage_jsp._jspservice(pollpage_jsp.java:195)     org.apache.jasper.runtime.httpjspbase.service(httpjspbase.java:70)     javax.servlet.http.httpservlet.service(httpservlet.java:722)     org.apache.jasper.servlet.jspservletwrapper.service(jspservletwrapper.java:432)     org.apache.jasper.servlet.jspservlet.servicejspfile(jspservlet.java:390)     org.apache.jasper.servlet.jspservlet.service(jspservlet.java:334)     javax.servlet.http.httpservlet.service(httpservlet.java:722)     org.springframework.web.servlet.view.internalresourceview.rendermergedoutputmodel(internalresourceview.java:238)     org.springframework.web.servlet.view.abstractview.render(abstractview.java:262)     org.springframework.web.servlet.dispatcherservlet.render(dispatcherservlet.java:1265)     org.springframework.web.servlet.dispatcherservlet.processdispatchresult(dispatcherservlet.java:1016)     org.springframework.web.servlet.dispatcherservlet.dodispatch(dispatcherservlet.java:965)     org.springframework.web.servlet.dispatcherservlet.doservice(dispatcherservlet.java:859)     org.springframework.web.servlet.frameworkservlet.processrequest(frameworkservlet.java:883)     org.springframework.web.servlet.frameworkservlet.doget(frameworkservlet.java:781)     javax.servlet.http.httpservlet.service(httpservlet.java:621)     javax.servlet.http.httpservlet.service(httpservlet.java:722)

here poll1dao.getvotes().

public hashmap<string, object> getvotes() {     // following line line 27, referenced in error message     return (hashmap<string, object>) this.getjdbctemplate().queryformap(             "select yes, no poll1 id = 1"); }

here poll1tag.dotag().

poll1dao poll1dao = new poll1dao();  public void dotag() throws jspexception, ioexception {     pagecontext pagecontext = (pagecontext) getjspcontext();     boolean foundcookie = cookiefound();          pagecontext.setattribute("foundcookiepoll1", foundcookie);         if (foundcookie) {             // following line line 23, referenced in error message             hashmap<string, object> poll1votes = poll1dao.getvotes();             pagecontext.setattribute("poll1yes", (int) poll1votes.get("yes"));             pagecontext.setattribute("poll1no", (int) poll1votes.get("no"));         } }

if using ioc container such spring's application context you should never create managed bean instances yourself. need pull instance out container - i.e. applicationcontext. otherwise not initalized necessary dependencies.

now question should ask - how can applicationcontext instance in jsp tag class. answer simple - how standard spring tags are doing that (i mean - go check link).

// example on how obtain bean jsp tag (ignoring context hierarchy) webapplicationcontextutils.getrequiredwebapplicationcontext(pagecontext.getservletcontext()).         getbeansoftype(poll1dao.class).values().iterator().next();

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