I am using jasper plugin to generate my report. All is fine but except my pdf is opening on the current tab, when I want to open it in a new tab.
I have no idea how to
This is going to be handled by the link you use to generate the report. Typically adding a target of _blank will do the trick. For example:
<g:link controller="myReports" action="whateverReport" target="_blank">Click for your report</g:link>
This will open the link in a new tab.
If you are using a form adding target to the form will submit the form to a new tab. For example:
<form name="myForm" action="whateverReport" method="POST" target="_blank">
or
<g:form name="myForm" controller="myReports" action="whateverReport" target="_blank">
You could even do so with javascript window.open
if you needed, but I will leave that example out of this answer as it's well documented elsewhere.