More facts about the JRE issue

I've downloaded IDEA build 661


I already have plenty of JREs:

- the one that comes with Microsoft Windows

- the one that I got from Sun (

- the one that is bundled with Sun's JAVA SDK (JDK) (

Now I also have the "special" JRE that is provided by IntelliJ (

As a matter of fact, I didn't have to use (download) the JRE from IntelliJ in order to run IDEA, using the following procedure instead:

a) Copy the "jre/" directory from the JDK install (or the JRE stand-alone install) to IDEA home.

b) Copy "tools.jar" from the JDK to "jre/lib" in IDEA home.

c) Copy "javac.exe" from "/bin" in the JDK to "jre/bin" in IDEA home.

These guidelines were provided by "Mike Aizatsky", from IntelliJ, as a tip to avoid downloading IntelliJ's own JRE. (I can't find the forum post anymore, otherwise, I'd give a link here)

Well, it works fine. In other words: IDEA works fine with the standard JRE (and some standard SDK components) installed in a specific location (IDEA home).

I understand that JetBrains has got support concerns and therefore provides its own JRE (or "JRE/SDK installation") in order to avoid time-consuming user troubleshooting.

I quite agree with the fact that it's better spending time on fixing "real" bugs in IDEA rather than providing support for users who can't get IDEA to run with their own JDK.

On the other hand, IDEA is a Java application, and as such it should run on any platform as long as a JVM is available. (see WORA principles)
IDEA needs tools from the JDK but IDEA users are developers (and customers by the way), therefore they have JDKs on their machines.
After all, it's just a matter of minimum requirements: JDK 1.4.1_01 (comes with both SDK and JRE).

So my point is: a majority of users already have the latest JDK, and they would like to use it to run IDEA. Instead of copying part of their JDK to IDEA home (or installing IntelliJ own's JRE package, which results the same), we would like to be able to point to our existing JRE/SDK. We would save space on the hard disk and avoid redondancy.

Like any Java-app, IDEA needs a JRE (JVM) for it to run. A pointer to the correct JRE (correct version) can be provided in "IDEA.bat", the current startup script.

Then, a nice SWING dialog could invite the user to tell IDEA where to find the SDK components ("tools.jar", and "javac.exe")

IntelliJ could still provide a lighter package for users who really don't want to have the latest SDK on their systems. But at least, it wouldn't have to be located in IDEA home and therefore be part of the application. It would just be convenient for some users.

This sounds rather simple to me and according to most of the posts I've read in this forum, users (current or future IntelliJ's customers) seem to be very concerned about having to install one "specific" JRE for IDEA.

As someone said in one of the posts: "Customer is always right". Well, at least we would like our feedback to be taken into account for future releases.

Thank you.


I agree,

I have too many java.exe's on my machine - 17 at the moment. They come with oracle products, they come with macromedia products, microsoft sticks one in, my company sticks some in on new machine installs.

Idea is for developers - I know how to download a jre from sun and click the setup button.


Build 662 is out !
And downloading now rocks !! (> 3 MB/s)

Well, I've downloaded the 3 different packages available at , but I'm planning to use "" only, without the provided JRE.

(I still have to copy my own JRE/SDK components into IDEA home though...)

Gosh, I hope IntelliJ engineers will read these posts and fix the JRE issue Let us use the JRE/SDK components we already have on our systems ! We don't want to have duplicate versions of JRE/SDK all over the place !! This is not what Java is all about



You have your own SDK 1.4.1_01, then follow this procedure:

a) Copy the "jre/" directory from the JDK install (or the JRE stand-alone install) to IDEA home.

b) Copy "tools.jar" from the JDK to "jre/lib" in IDEA home.

c) Copy "javac.exe" from "/bin" in the JDK to "jre/bin" in IDEA home.

It works fine with build #662 too.



Using links under UNIX/LINUX provides an alternative to duplicating files. Here is a link in this forum for posts that explain how to use links in win32:



If this is an informal vote or poll, then I agree, don't put a jre in the intellij home dir. I agree for all of the reasons stated in the previous posts. Yes I can go through the steps of copying a current jre, and adding tools.jar and the javac.exe to the appropriate locations, but I don't want to. Seems like a cheezy fix for a first class product.


Actually, all you need to do is

  • copy <JDK1.4.1_01-HOME>/lib/tools.jar to <IntelliJ-IDEA-HOME>/jre/lib

  • edit IntelliJ-IDEA/bin/idea.lax and change the to point to <JDK1.4.1_01-HOME>/jre/bin/java.exe


I also agree for all of the reasons stated in the previous posts and don't like idea to provide its own jre.


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