List<String> () { String instrumentationUtilPath = getResourcePath(NotNullVerifyingInstrumenter.class); File instrumentationUtil = new File(instrumentationUtilPath); if (instrumentationUtil.isDirectory()) { //running from sources: load classes from .../out/production/intellij.java.compiler.instrumentationUtil.java8 return Arrays.asList(instrumentationUtilPath, new File(instrumentationUtil.getParentFile(), "intellij.java.compiler.instrumentationUtil.java8").getAbsolutePath()); } else { //running from jars: intellij.java.compiler.instrumentationUtil.java8 is located in the same jar return Collections.singletonList(instrumentationUtilPath); } }