Hi Jain,
Before answering to your questions,may i know the reason behind looking for a long term job in UK??
Are you planning to relocate to UK??
Anyways,please find below my answers.
How do i get into uk for java/j2ee job for long term?
If your company provides you with an onsite opportunity you can. Else,you have to apply for Highly skilled Migrant Visa
(Tier 1) which, i believe has been stopped from 23 Dec 2010.
Please check
http://www.ukba.homeoffice.gov.uk/workingintheuk/tier1/general/ for further info
what kind of visa(uk) should i apply for long term?
Again,check in website
how much salary i can be expect as a 4 years exp guy?
No idea.Maybe someone working in UK can provide some information
how many days will takes to find and get a jobs there for 4 years java/j2ee guy?
Absolutely nobody can answer this as this depends on multiple factors.
1. Your technical skills set
2. The current market in UK
3. Demand for your skills in UK
what is minimum and maximum salary i can ask if i get job?
You can check in Google
Can i apply and attend a interview in india for uk jobs?
I don't think so.I haven't heard of people getting jobs in UK from India through telephonic interviews.
And please note that it is India NOT india
And,of course,Ulf's advice was perfect.Java/J2EE skill sets are already available in plenty.