Selecting the JDK version the IDE will run under

Windows

JDK is bundled with all the product installers and it's recommended that you will use the provided JDK version unless there are any specific issues.

32-bit JDK is located in IDE_HOME\jre directory and is used by the 32-bit product executable.

To run the IDE in 64-bit mode you will need to download and install 64-bit JDK (not JRE) distribution and install it yourself. IDE will find and use it from the registry when you run the 64-bit .exe file (available only for IntelliJ IDEA right now, other products can use the .bat file to run in 64-bit mode).

<product>.exe uses this JDK search sequence:

1. IDEA_JDK / WEBIDE_JDK / PYCHARM_JDK / RUBYMINE_JDK environment variable (depends on the product, WEBIDE_JDK applies to both WebStorm and PhpStorm)

2. ..\jre directory
3. system Registry
4. JDK_HOME environment variable
5. JAVA_HOME environment variable

idea64.exe uses this JDK search sequence:

1. IDEA_JDK_64 environment variable
2. ..\jre64 directory
3. system Registry
4. JDK_HOME environment variable
5. JAVA_HOME environment variable

It’s also possible to start the IDE with <product>.bat file located in the bin directory, it uses the following JDK search sequence:

1. IDEA_JDK / WEBIDE_JDK / PYCHARM_JDK / RUBYMINE_JDK environment variable (depends on the product)
2. ..\jre directory
3. JDK_HOME environment variable
4. JAVA_HOME environment variable

Environment variable must point to the JDK installation home directory, for example:

c:\Program Files (x86)\Java\jdk1.7.0_17

• /create-i4j-log command line switch can be used with the .exe to trace the JDK search sequence and find out why the specific JDK was chosen.
• The actual JDK version used by the IDE can be verified in Help | About dialog (open any project to access the menu).
• Define IDEA_JDK / WEBIDE_JDK / PYCHARM_JDK / RUBYMINE_JDK variable depending on the product to override the default version from IDE_HOME\jre.
• Use Rapid Environment Editor to add/edit the variables, it will detect incorrect paths.

Linux

• Refer to the distribution specific instructions for changing the default JDK version (Ubuntu Java documentation).
• It's recommended that you will use the latest version of Oracle JDK or OpenJDK available for your system (OpenJDK 1.6 is not supported, please use 1.7 or later versions).
• Check bin/<product>.sh file for the JDK search order, it's similar to Windows in terms of the environment variable names.
• You can define JDK home environment variable directly in the .sh file to override system defaults.
• Check this answer if you need to install the JDK manually on Linux.
• If you have problems with ugly fonts, check this thread comments for the tips.
• Help | About will show the actual JDK version.

Mac OS X

• Our latest IDE versions come with the bundled custom JDK 1.8 which contains the fixes for most known OpenJDK bugs. Should you need to use a different Java version, please refer to this blog post.