Upgrading from Java SE to Java EE

[Steven Barn]

Excuse the newbie stylee questions...

I currently have Java SE installed and would like to download and install Jave EE. However i have downloaded "Java EE 6 SDK with JDK 7 U3" - which is confusing as it seems to concentrate on the Glassfish server, which i don't think i really want.
Also after downloading this i have checked the contents of the \bin folder and these seem identical to my already installed version of Java, which i'm certain is not EE edition.

Could anyone please help with some detailed instructions - currently i have a nice folder structure setup that contains my existing Java install and have all the correct settings, system variable wise - so was sort of hoping for an update that would more or less add the additional files rather than starting again.

Not sure how to proceed.

Thanks
Steve

[Campbell Ritchie]

Welcome to the Ranch

There is a link on the Oracle site. You can usually specify the location for the folders when you fun the installers (at least for SE you can).
Does that help you at all? I don’t think the contents of the bin folder will be any different. There will be more files in the library folders, however. I suggest you try it, by importing a class from an EE only package, and seeing what happens. If it compiles, then assume all is well.

[Steven Barn]

Thanks for the welcome and quick reply.

I've checked both the \bin and \lib folder and they are identical.

Basically i have a load of code samples from a recent training course which won't run as they have many imports statements that reference EE libraries - such as "import javax.servlet.*;".

The EE download defaulted to a c:\glassfish folder - it did give me the option of changing the directory but i couldn't point it as my already installed Java SE as it complained that it needed an empty directory.

My question is, i suppose - do i need to start from scratch by installing EE and amending my system variables etc or can is there any easy upgrade option?
( i have looked at the link posted but this doesn't state anything obvious on this)

Thanks
Steve

[Steven Barn]

I may already have the EE version installed as i did install the EE version of eclipse - so i don't know if Java EE comes bundled with the IDE.

Also i did run through as servlet example using the EE eclipse some time back - is there a definitive way to check if i have the EE version installed ?

If i run java -version from the cmd prompt, this is the result

Java version "1.7.0_03"
Java<TM> SE Runtime Environment <build 1.7.3_03-b05>
Java Hotspot<TM> 64-bit Server VM <build 22.1-b02, mixed mode>

Thanks

[Joanne Neal]

Java EE is an extension of Java EE intended for developing Enterprise level applications. You have to have Java SE installed to use Java EE but if you already have SE installed and don't want to chnage the version, you should download the EE install that doesn't include a JDK.

[Carlo Moore]

For your example to work, you will need to have a JDK installed and you'll be referencing some EE jars. You don't really need to compare bin folders or anything like that.
In your eclipse environment you'll be setting a couple of things. Your jre should be correct by default so no change there, your project's Java Build Path will need changes though. The build path, you're going to be pointing to some of the jars from the EE installation, such as the servlet-api jar. So that all your compile errors within eclipse are resolved.

What you have to remember is that your eclipse class path is not going to be the same as your deployment class path. For instance, if you want to run your example on jboss, you'll have to get your servet-api jar deployed to jboss, so it's in the jboss class path. Or if you want to run your example from the command line you'll have to add your jar into the java classpath.

I work a lot with Java EE and I've not downloaded the Java EE. I usually have a specific JDK / JRE installed though. All the Java EE jars / dependencies have been automatically downloaded for me using maven.

The EE version of eclipse is only going to provide you with some EE development tools. You could do the same development with pretty much any version of eclipse.

[Steven Barn]

Carlo - thanks, that makes perfect sense.

So, i'll continue to work from my JavaSE libraries but reference the jar files in the EE install where required ? At least until i get round to understanding and using Maven.

Thanks
Steve