Error:java: invalid source release: 8 in Intellij. What does it mean?

Question

Im trying to compile some code in I'm using Intellij Ultimate 13.1.4, but I get the following error and I have no idea what it means:

Information:Using javac 1.7.0_55 to compile java sources
Information:java: Errors occurred while compiling module 'Example'
Information:Compilation completed with 1 error and 0 warnings in 3 sec
Information:1 error
Information:0 warnings
Error:java: invalid source release: 8

My guess is that its something related to Java 8 vs Java 7, but I have no idea what specifically. I've tried to Google around for this message, but they either talk about javac or target release, so it doesn't exactly seem to apply.

Solution 1

I had the same issue when "downgrading" a project from Java 8 to Java 6. The reason was that it was not changed at all places in IntelliJ.

In IntelliJ 13.1.4 I had to change Java and SDK version on the following places not to get this error:

• File -> Project Structure -> Project Settings
• File -> Project Structure -> Module Settings -> Tab: Sources: Language Level
• File -> Project Structure -> Module Settings -> Tab: Dependencies: Module SDK
• File -> Settings -> Compiler -> Java Compiler -> Target bytecode version

The last bullet was the one that was not updated in my case. Once I changed this, the error disappeared.

Solution 2

Check your pom.xml first (if you have one)
Check your module's JDK dependancy. Make sure that it is 1.8
To do this,go to Project Structure -> SDK's
Add the path to where you have stored 1.8 (jdk1.8.0_45.jdk in my case)
Apply the changes
Now, go to Project Structure ->Modules
Change the Module SDK to 1.8
Apply the changes

Voila! You're done

Solution 3

Change in pom.xml 1.6 to 1.8

<plugin>
    <artifactId>maven-compiler-plugin</artifactId>
    <configuration>
        <source>1.8</source>
        <target>1.8</target>
    </configuration>
</plugin>

Solution 4

For Gradle users having this issues, if nothing above helps this is what solved my problem - apply this declarations in your build.gradle files:

targetCompatibility = 1.6 //or 1.7;1.8 and so on
sourceCompatibility = 1.6 //or 1.7;1.8 and so on

Problem solved!

Solution 5

If you are using Gradle as a build tool and you get this error when executing a Gradle task i.e TomcatRun take a look to my other answer to the same question

javac: invalid target release: 1.8

View more solutions

Comments

[bitoiu]

the one killing me was this one: File -> Settings -> Compiler -> Java Compiler -> Target bytecode version . Thanks.

[Emil]

I was running into this issue as well, but none of the above worked. I had to do IntelliJ IDEA -> Preferences... -> Build, Execution, Deployment -> Build Tools -> Gradle -> Gradle JVM, in case anyone is running into this issue whilst using Gradle.

[chazzlabs]

Thanks! This resolved my issue after the above answers didn't.

[Mia]

Source: Language Level change to 7 - Diamonds, ARM, multi-catch etc. for IDEA 15

[iusting]

This should be the accepted answer. As a small heads-up, in IntelliJ IDEA 15, point 4 has moved to Preferences -> Build, Execution, Deployment -> Compiler -> Java Compiler.

[jordanpg]

There is also a JRE selection in some run/debug configurations. For example, Tomcat run/debug configs have a "JRE" selector that can cause this error.

[jordanpg]

Also don't forget the JDK IDEA is running under as well as the JDK used by the underlying OS (for example if you use jenv). See: intellij-support.jetbrains.com/hc/en-us/articles/…

[AnkitSablok]

I faced the same error and the solution mentioned worked out perfectly fine, the thing is one needs to know what language level was the project compiled in and change the project to use that language level.

[Amar Gajbhiye]

This really helped. I had changed the version from all the places except Project SDK.

[Michael Coxon]

I tried all of this in 2018.3.6 and nothing worked - I blew away the .idea directory and re-initialised the project - then it worked.

[Indrajeet Gour]

One more thing i did apart from the mentioned step, edit configuration -> application -> select the your application and check the JRE drop-down and select which you wanted to have in case it was jdk11.

[Uzair]

If you don't SDK 12. Just add the latest one

[Admin]

what a legend tysm

[payne]

Ended up having to modify the value of the cloned repo in its root build.gradle (the sourceCompatibility value).