Use javac API in plugin

I want to run custom AnnotationProcessor from the plugin and I've found that javac API can be invoked easily from the java code itself. Like

compiler = ToolProvider.getSystemJavaCompiler();
...
task.setProcessors(Collections.singleton(p));

However, when I tried to invoke it from the Intellij Plugin, there was this error

> Error: Unable to find package java.lang in classpath or bootclasspath

I have correct jre setup, and I can build and compile my project from the IntelliJ. So I can't see why the classpath is incorrect.

Things that didn't help

Using another class loader to load compiler class

ClassLoader.getSystemClassLoader();
Object compiler = callStaticMethod(classLoader, JavacTool.class, "create");

Adding compiler options to the compilation task

String root = "/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home";
final List<String> options = Arrays.asList(
        "-Xbootclasspath/p:" + root,
        "-classpath", root);
JavaCompiler.CompilationTask task = compiler.getTask(outWriter, fileManager, diagnostics, options, Collections.singleton(qualifiedName), Collections.singleton(source));

Adding url to the UrlClassLoader before calling compiler

String pathname = "/Library/Java/JavaVirtualMachines/jdk1.8.0_181.jdk/Contents/Home/jre/lib/rt.jar";
File pathElement = new File(pathname);
URL url = pathElement.toPath().normalize().toUri().toURL();
callInstanceMethod(urlClassLoader, "addURL", new Class[]{URL.class}, url);

I'm still seeing this error "Unable to find package java.lang in classpath or bootclasspath" 

Anyone has ideas how to configure plugin to run javac API?