Java EE for a .NET developer

I have always been a .NET developer. I have created some Swing apps in the past and I handle the java language pretty well but I don't have much knowledge of Java EE or any other relevant technologies for entreprise application development.

1) What are the relevant technologies for 开发者_开发技巧entreprise development in java?

2) What are the best places online to learn them?

3) Is there any online repository of information for java like the MSDN Library?

4) Which development tools are recommended for this technologies?

Thanx

What are the relevant technologies for entreprise development in java?

Servlets/JSP are the most important I'd say. It's part of the Java EE spec and the basis for 99% o the Java Web frameworks. The other is the Spring framework, which is almost a "must-have".

What are the best places online to learn them?

Writing code, of course.

Is there any online repository of information for java like the MSDN Library?

There's the JDK 6 documentaiton and others.

Which development tools are recommended for this technologies?

An IDE is the most important thing. There are basically three to choose from: Eclipse (free; most popular), IntelliJ IDEA (commercial; my personal favourite) and Netbeans (free).

I'm surprised no one mentioned this year, but the J2EE 5 API docs are separate from the JDK 6 API docs.

Your First Cup: An Introduction to the Java EE Platform may also be useful.

In addition to Cletus' answer, you'll want to take a look at Apache Commons, which is where to find the classes and methods you'll often want that were more or less left out of the core Java libraries.

For what it's worth, I'd start with Eclipse as my IDE, and change later. It's free, and by far the most common IDE for Java out there.