Configuring SAML2 with SSO

Hi Guys,
I need help in configuring SAML 2 browser based SSO, I've below test scenario-
1> We have Java based product which have local users in its database, now I want to test browser based Single Sign On using SAML2.0
I'm referring this document from RedHat site--> https://access.redhat.com/documentation/en-us/red_hat_jboss_enterprise_application_platform/7.0/html-single/how_to_set_up_sso_with_saml_v2/

For creating IDP - what is pre-requisite or third party software's / opensource packages required ?
In chapter 2 in the said document its referred as -"Configure the web.xml for an IDP" - what is this web.xml, which application's web.xml we need to configure ?

Also is anybody have good step by step guide will be great.

Thanks,
Mangesh