Intellij IDEA Java classes not auto compiling on save

Question

Yesterday I switched to IntelliJ IDEA from Eclipse.

I am using JRebel with WebSphere Server 7 as well.

Everything now seems to be working somewhat fine, except that when I modify a Java file, and hit save, IntelliJ does not re-compile the file, in order for JRebel to pick it up.

The Eclipse "Build Automatically" feature resolved this issue.

In IntelliJ IDEA, I have to hit CTRL+SHIFT+9 to re-compile the relevant class for JRebel to pick it up. If changes are done across two files, I have to do this on each and one of them and since IntelliJ uses the save all mechanism, its pretty hard to know what to recompile manually which I am not really interested in doing either.

Isn't there a way to make IntelliJ to do this on its own?

Answer 1

For IntelliJ IDEA 12+ releases we can build automatically the edited sources if we are using the external compiler option. The only thing needed is to check the option "Build project automatically", located under "Compiler" settings:

Also, if you would like to hot deploy, while the application is running or if you are using spring boot devtools you should enable the compiler.automake.allow.when.app.running from registry too. This will automatically compile your changes.

Using Ctrl+Shift+A (or ⌘+Shift+A on Mac) type Registry once the registry windows is open, locate and enable compiler.automake.allow.when.app.running, see here:

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For versions older than 12, you can use the EclipseMode plugin to make IDEA automatically compile the saved files.

For more tips see the "Migrating From Eclipse to IntelliJ IDEA" guide.