Eclipse Luna 1.7 to 1.8 errors - java

I was working in Eclipse Luna and tried to write a static method in an interface but it gave me an error. I moused over it and I forgot what it said but it was something like ... 1.8 JRE. So I clicked it and now there's an error on almost every line saying things like:
String cannot be resolved to a type
and
java.lang.Object cannot be resolved
How to go back to fix it?

The problem here is a confusion in your eclipse between the Installed JRE in your system and the used JRE in your project, so to resolve point to the installed JRE in your system, like this:
Open your project build path configuration:
Right click in your project, then choose properties-->Java Build Path.
2. Add a new JRE System Library:
Click the button add Library then choose JRE System Library:
3. Choose the installed JRE Library:
Click the Installed JREs... button and choose the installed JRE in your system.
Hope it helps.

Related

what broke up in my eclipse?

For some reason, whenever I create a new Java project, I can't compile anything and I get the following errors:
The project cannot be built until build path errors are resolved
Unbound classpath container: 'JRE System Library[OSGi/Minimum-1.2]' in project 'MyProject'
This didn't use to ever happen, and it used to be very easy to create new Java projects.
Open Properties by Right clicking on your project
Select Java Build Path
Under the Libraries, select JRE System Library under the Libraries.
Then click Edit...
select Alternate JRE under System library
If any, select JRE from the drop down and click finish
If none, click installed JREs...
Under installed JRE Types, select Standard VM, and click next.
Set your JRE home and JRE name and click finish.
Under the install JREs select your newly added JRE and click OK
After that, Repeat step 6.
1.Check whether JRE is properly installed in your system and it is added in Eclipse.
You can try re-installing JDK in your system and
Add JRE to Eclipse from Window -> Preferences -> Java -> Installed JREs.

Cannot create JavaFX project in Eclipse Kepler

I've installed JDK 1.7.0_45.
I've got my JAVA_HOME system variable pointing to installation folder.
Typing java -version in comman line results in "java version "1.7.0_45" output.
I've got Eclipse Kepler with e(fx)clipse plugin.
In Eclipse, in "Installed JRE-s" tag I've added the new JDK and set is as default.
I clicked New -> JavaFX Project and filled Project name.
The only buttons available are "Back" and "Cancel". I don't see any errors.
The only other element available is "Configure" button in "JavaFX Runtime Configuration" section.
The section contains message saying: "currently there are no configured runtimes".
I'm confused. I don't have a separate JavaFX runtime, and when I go here: http://www.oracle.com/technetwork/java/javafx/downloads/index.html it points me to JDK 7 I've already downloaded with explanation that "JavaFX is co-bundled with JDK 7 for Windows, Mac and Linux, it contains all the latest features and security fixes."
What am I missing? How can I create a JavaFX project in Eclipse?
I've found the solution.
I've uninstalled all plugins related to JavaFX (it turned out there were two of them) and then reinstalled e(fx)clipse from update site: http://download.eclipse.org/efxclipse/updates-nightly/site.
Everything works as expected now.
You only have to add the 'jfxrt.jar' file to the path of your project. And it works! Is not necessary another plugins, just that.
P.D: It works for me on Mac OS with eclipse Kepler. In case it didn't work, install e(fx)clipse and try again.

Groovy and grails jdk issue

I wish I could give you guys more information on what's going on, but I really have no idea. I am trying to install groovy and grails tools suite from springsource and I am having trouble configuring it to work properly. I have the most up to date JDK, and the preferences show it, but I still get warnings and it does not build. I have posted some pictures below to show what is going on.
on your GGTS go to window
select java
select installed JREs
add-> Standard VM
jRE home select directory up to C:\Program Files\Java\jdk1.6.0_18
select jdk1.6.0_18 from installed JREs
I faced a similar issue (I am sure it is the exact issue) - Here are the steps to ensure it works correctly, I struggled with initially but this got it going.
Install JDK from http://www.java.com ,in a directory where there are NO SPACES in the path
Set JAVA_HOME to your JDK installation
Ensure %JAVA_HOME%\bin; is in your PATH variable.
On the command prompt run java -version, it should give you the path where JDK is installed
Install STS Springsource Tool suite.
Run your STS and create a new grails project and run it.
Let me know if that does not work.
It might be that you are launching Eclipse with a JRE even though you have a JDK installed as one of the compilers in your workspace. To find out if you are launching with a JRE or JDK, go to Help -> About GGTS -> Installation details -> Configuration
Look for the -vm option and make sure it is a JDK not a JRE.

Can't locate JDK x64 in intellijIDEA

I am starting a new project, and the client requires us to work in IntelliJIdea. I installed it and tried to do the ant build. It turns our I need 64 bit jdk for the build. So I installed it. Now, however I need to configure it in IntelliJIdea. Here is the message I get:
JDK (1.6_x64) needed to run this ANT target is not configured. Please
update your settings in the Project | Libraries menu.
Can somebody help me locate this Project | Libraries menu menu please?
Press ctrl+alt+shift+s, and on the left hand side you'll see Project Settings -> Libraries.
Q: Where do I configure project JDK?
A: In the Project Settings dialog.
To add a JDK to project, press Ctrl+Alt+Shift+S, under Platform
Settings click JDKs and specify JDK path. After that, you can click
Project and specify which of JDK you have configured is used in the
current projects. Remember that JDKs are configured at IDE level, so
when you create another project, you won't need to add the same JDK
again.
reference :
http://www.jetbrains.com/idea/documentation/migration_faq.html

How to change JDK version for an Eclipse project

I need to write a project that's only compatible with Java 1.5. I have Java 1.6 installed. Is there some form of backwards compatibility to get Eclipse to compile with 1.5?
Do I have to install Java 1.5 to get it to show here? Or maybe there is another way?
.
Click on the Add Library button. It brings your screen to point to the Java location.
Select "Directory", button right besides JRE home and point to the installed folder location.
Even though you want to just 1.5 compiler project, you can achieve it by changing compiler settings in Eclipse instead of removing 1.6 JRE and add 1.5 JRE.
GOTO -->JAVA--Compiler---> and change compiler level to `1.5` instead of `1.6`
As davidfmatheson suggested,
Just be careful, especially if you're setting this up for a team of people to work on. If anyone uses anything that is new or changed in 1.6, it will compile, but not run in an environment with JRE 1.5.
Click on the Window tab in Eclipse, go to Preferences and when that window comes up, go to Java → Installed JREs → Execution Environment and choose JavaSE-1.5. You then have to go to Compiler and set the Compiler compliance level.
Right click project -> Properties -> Java Build Path -> select JRE System Library click Edit and select JDK or JRE after then click Java Compiler and select Compiler compliance level to 1.8
If you are using maven build tool then add the below properties to it and doing a maven update will solve the problem
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
In the preferences section under Java -> Installed JREs click the Add button and navigate to the 1.5 JDK home folder. Then check that one in the list and it will become the default for all projects:
Eclipse - specific Project change JDK Version -
If you want to change any jdk version of A specific project than you have to click ---> Project --> JRE System Library --> Properties ---> Inside Classpath Container (JRE System Library) change the Execution Environment to which ever version you want e.g. 1.7 or 1.8.
The JDK (JAVA_HOME) used to launch Eclipse is not necessarily the one used to compiled your project.
To see what JRE you can select for your project, check the preferences:
General → Java Installed JRE
By default, if you have not added any JRE, the only one declared will be the one used to launched Eclipse (which can be defined in your eclipse.ini).
You can add any other JRE you want, including one compatible with your project.
After that, you will need to check in your project properties (or in the general preferences) what JRE is used, with what compliance level:
(source: standartux.fr)
See the page Set Up JDK in Eclipse. From the add button you can add a different version of the JDK...
As I was facing this issue minutes ago, in case you are trying to open an existing project in an environment with a newer JDK, make sure you pdate the JDK version in Project Properties -> Project Facets -> Java.

Categories