Cannot access 'java.io.Serializable' which is a supertype of 'kotlin.String'. Check your module classpath for missing or conflicting dependencies

I have a new Kotlin project in Eclipse (I installed the kotlin plugin).
However this code:

val a: Int = 10000
println("Your Int Value is "+a);


causes this error:


ERROR: Cannot access 'java.io.Serializable' which is a supertype of 'kotlin.String'. Check your module classpath for missing or conflicting dependencies.

What is the source of this error? How can I fix it?

**I have seen the other posts on stackoverflow but they all talk about intellij and not Eclipse.**

I got this error while using kotlin in eclipse. In my system, JDK was not installed previously. I installed JDK 15 in the PC and set the path in kotlin plugin settings in eclipse (path: Window -> preferences -> Kotlin -> Compiler -> JDK Home)

IntelliJ user here.

In my case, my project settings were (somehow) changed to reference a Java SDK at a path that doesn't exist on my system (hence the inability to find various Java classes).

I fixed this by:

1. Opening the project/module settings through `File -> Project Structure`
1. In the `Project Structure` dialog, find the `Platform Settings` section and click on `SDKs`.
1. For each JDK entry, either remove or fix the entries that don't show any content in the `Classpath` tab.

For me fix was by deleting "project"/.idea/misc.xml file