val causes intellij to show an invalid error when used alongside an anonymous class

val is supposed to infer the type of a value and make it final, so you should be able to use them in anonymous classes. In fact you can do this! Intellij doesn’t believe you though:

public class ValTest {
    public void doSomething() {
        val foo = new Foo();
        val bar = new Bar();
        foo.setBazListener(new BazListener () {
            @Override
            public Bar onBaz() {
                return bar;
            }
        });
    }
}

When using this code there is an error on bar in return bar that says “Variable bar is accessed from within inner class, needs to be declared final”. I agree, however val indeed does make it final. This code actually compiles and runs fine. I’m currently using android studio 1.2.1.1, and I think it’s based off of idea 14.

[mplushnikov]

The update should be available in the next version of plugin (0.12) and will work only for new versions of IntelliJ Idea (2016.2)(build >=146.1154)

[mplushnikov]

I just filed a issue IDEA-153706 for Intellij.