StandardJavaFileManager fileManager = compiler.getStandardFileManager(null, null, UTF_8);
        Iterable<? extends JavaFileObject> compilationUnits = fileManager.getJavaFileObjectsFromFiles(sourceFiles);
        List<String> arguments = Arrays.asList("-d", outputFolder.getAbsolutePath());
        JavaCompiler.CompilationTask delegate = compiler.getTask(output, fileManager, null, arguments, null, compilationUnits);

                throw new AssertionError(message)
            }
        }

        def diagnosticListener = checkDiagnostic.asType("javax.tools.DiagnosticListener" as Class)

        def input = fileManager.getJavaFileObjectsFromFiles(Arrays.asList(sourceFile))
        compiler.getTask(null,
            fileManager,
            diagnosticListener,
            null,
            null,
            input).call();

            List<File> filesToCompile = outputSourceFilesToSourceDir(srcDir, classes);
            if (dstDir.exists() || dstDir.mkdirs()) {
                Iterable<? extends JavaFileObject> sources = mgr.getJavaFileObjectsFromFiles(filesToCompile);
                JavaCompiler.CompilationTask task = compiler.getTask(null, mgr, ds, options, null, sources);
                task.call();
            } else {

        StandardJavaFileManager standardFileManager = compiler.getStandardFileManager(diagnosticToProblemListener, null, charset);

        Iterable<? extends JavaFileObject> compilationUnits = standardFileManager.getJavaFileObjectsFromFiles(spec.getSourceFiles());
        boolean hasEmptySourcepaths = JavaVersion.current().isJava9Compatible() && emptySourcepathIn(options);