Intellij - Unable to use newer Java 8 classes - Error : “Usage of API documented as @since 1.6+..”

Question

I\'m trying to use a java.lang.function.Function in my java 8 code base, but i keep getting the following error in Intellij.

Usage of API

Answer 1

I just fixed it as follows:

Right click the project -> Open Module Settings -> Modules -> Sources -> 8 or higher

And then

If still encounter the error and using maven, you have to add the build configuration in your pom.xml:

    
        
            org.apache.maven.plugins
            maven-compiler-plugin
            
                1.8
                1.8