How to have Eclipse use JDK8 to compile a project?

Question

I'm experimenting with the new jdk8 what is available here http://jdk8.java.net/lambda/

I'm able to compile and run my project from command line.

I'm also able to add this new JDK to Installed JREs in Eclipse. However, I'm not able to have Eclipse to compile and run the project with this JDK.

I'm trying to change the settings on Project Properties/Java Compiler but the Use [JDK] compliance from execution environment on the 'Java Build Path' checkbox is disabled and no matter whatever I click on this page, I cannot make it work.

I have Eclipse Platform Version: 3.7.1

Any ideas?

thx

score 21 · Accepted Answer · edited Jul 26 '12 at 18:30

21

Eclipse uses a built-in compiler rather than javac. The built-in compiler obviously doesn't support Java 8 yet.

You can define a custom builder for your project which will call your javac. In the project's preferences, go to "Builders", add a new custom builder (which can be either an Ant script or an executable program) and disable the default built-in Java builder.

Afterwards, running the project with the JDK of your choice shouldn't be a problem - adding it to the "Installed JREs" preference page (as you did) should be sufficient.

edited Jul 26 '12 at 18:30

Deepak Azad

7,903
2
34
49

answered Nov 14 '11 at 14:43

Eli Acherkan

6,401
2
27
34

5

[This post](http://tuhrig.de/?p=921) explains pretty well how to do it. Note that you will probably need to adjust the `javac` path arguments. – Michael Jess Mar 22 '13 at 09:18
3

Care to update now that the landscape has changed both for Eclipse and Java? – Ray Mar 19 '14 at 12:19
1

what if your eclipse can't start up? – Kebab Programmer Mar 17 '15 at 21:54

Eng.Fouad · Answer 2 · 2013-10-22T22:44:04.503

11

Eclipse now supports JDK 8 EA:

The Eclipse JDT/Core team is pleased to announce the availability of early access builds with support enabled for the following Java 8 features.

We recommend that you start with a clean install of

Either 4.3.1 or 4.4 M2 SDK

Update the JDT/Core, JDT/UI bundles from http://dist.springsource.com/snapshot/TOOLS/java8/e43

This update site is set up to periodically rebuild and package the relevant projects from the top of the BETA_JAVA8 development branch.

Source: http://dev.eclipse.org/mhonarc/lists/eclipse-dev/msg09679.html

EDIT:

After upgrading eclipse, you need to change the JDK and the compiler level. Here is a screenshot of using lambda within Eclipse:

enter image description here

edited Oct 22 '13 at 22:44

answered Oct 22 '13 at 22:21

Eng.Fouad

115,165
71
313
417

Oops, it seems that `sorted()` doesn't work well with `parallelStream()`. – Eng.Fouad Oct 22 '13 at 23:02
Well, it turns out that I need to use `forEachOrdered()` instead of `forEach()`: http://stackoverflow.com/questions/19529982/java-8-parallelstream-with-sorted – Eng.Fouad Oct 22 '13 at 23:33

score 5 · Answer 3 · answered Nov 01 '14 at 23:08

5

go window->preferences->Java->Installed JREs->execution environment->Java SE-1.8

answered Nov 01 '14 at 23:08

Mustafa Alghali

51
1
3

score 3 · Answer 4 · answered Sep 24 '17 at 12:19

3

I did it this way:

1.Right click on JRE System Library on Package Explorer and select Properties (On your right side)

Change your execution environment.

answered Sep 24 '17 at 12:19

Hunter

3,080
20
23

score 2 · Answer 5 · answered Nov 14 '11 at 14:28

2

You can pretty much forget about that, as even the plan for eclipse 3.8 only says "Start to work on Java 8 support."

Working with the bleeding edge has its drawbacks...

answered Nov 14 '11 at 14:28

Michael Borgwardt

342,105
78
482
720

Thanks! I don't accept it right now, I'm waiting if somebody could come up with a suggestion/workaround. – bpgergo Nov 14 '11 at 14:43

How to have Eclipse use JDK8 to compile a project?

5 Answers5

Linked