java.io.File not working

[Losin6450]

When using a node instance the java.io.File class doesn't work

[Losin6450]

its specifically the File.exists() method that doesn't work

[caoccao]

Please leave more info for the troubleshooting. OS, CPU arch, source code, etc.

[Losin6450]

its for a Minecraft plugin

public class Grakkit extends JavaPlugin implements CommandExecutor {

    V8Runtime runtime;
    JavetJVMInterceptor interceptor;
    @Override
    public void onEnable() {
        try {
            saveDefaultConfig();
            reloadConfig();
            String main = getConfig().getString("main", "index.js");
            String mode = getConfig().getString("mode", "js");
            if (mode.equalsIgnoreCase("node")){
                runtime = V8Host.getNodeInstance().createV8Runtime();
            } else {
                runtime = V8Host.getV8Instance().createV8Runtime();
            }
            runtime.setConverter(new JavetProxyConverter());
            interceptor = new JavetJVMInterceptor(runtime);
            interceptor.register(runtime.getGlobalObject());
            runtime.setV8ModuleResolver(new IV8ModuleResolver() {

                private Path DEFAULT = getDataFolder().toPath();
                private Path LAST = getDataFolder().toPath();

                @Override
                public IV8Module resolve(V8Runtime v8Runtime, String file, IV8Module iv8Module) throws JavetException {
                    try {
                        String filename = file.endsWith(".js") ? file : file + ".js";
                        Path f = LAST.resolve(filename);
                        if (Files.exists(f)) {
                            LAST = f.getParent();
                            V8Module module = v8Runtime.getExecutor(Files.lines(f).collect(Collectors.joining("\n"))).setResourceName(f.toFile().getAbsolutePath()).compileV8Module();
                            return module;
                        } else {
                            LAST = DEFAULT;

                            f = LAST.resolve(filename);
                            if (Files.exists(f)) {
                                LAST = f.getParent();
                                V8Module module = v8Runtime.getExecutor(Files.lines(f).collect(Collectors.joining("\n"))).setResourceName(f.toFile().getAbsolutePath()).compileV8Module();
                                return module;
                            }
                            return null;
                        }
                    } catch (Exception e){
                        e.printStackTrace();
                    }
                    return null;
                }
            });
            runtime.allowEval(true);
            runtime.getGlobalObject().set("Class", Class.class);
            runtime.getGlobalObject().set("Logger", getLogger());
            File file = new File(getDataFolder(), main);
            if (!file.exists()){
                file.getParentFile().mkdirs();
                file.createNewFile();
            }
            V8StringExecutor stringExecutor = (V8StringExecutor) runtime.getExecutor(Files.lines(file.toPath()).collect(Collectors.joining("\n")));
            stringExecutor.setModule(true);
            stringExecutor.setResourceName(file.getAbsolutePath());
            stringExecutor.execute();
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    @Override
    public void onDisable() {
        if (runtime != null){
            try {
                runtime.await();
                interceptor.unregister(runtime.getGlobalObject());
                runtime.close();
                System.gc();
            }catch (Exception e){
                e.printStackTrace();
            }
        }
    }

}
``` when using normal v8 runtime there is no issues but when using node i get this error when trying to use java.io.File 

java.io.IOException: Den angivne sti blev ikke fundet
at java.io.WinNTFileSystem.createFileExclusively(Native Method) ~[?:1.8.0_412-412]
at java.io.File.createTempFile(File.java:2063) ~[?:1.8.0_412-412]
at net.minecraft.server.v1_16_R2.Convertable$ConversionSession.a(Convertable.java:303) ~[spigot.jar:git-Spigot-b5a13e6-0d8350a]
at net.minecraft.server.v1_16_R2.WorldServer.save(WorldServer.java:768) ~[spigot.jar:git-Spigot-b5a13e6-0d8350a]
at net.minecraft.server.v1_16_R2.MinecraftServer.saveChunks(MinecraftServer.java:674) ~[spigot.jar:git-Spigot-b5a13e6-0d8350a]
at net.minecraft.server.v1_16_R2.MinecraftServer.stop(MinecraftServer.java:741) ~[spigot.jar:git-Spigot-b5a13e6-0d8350a]
at net.minecraft.server.v1_16_R2.DedicatedServer.stop(DedicatedServer.java:647) ~[spigot.jar:git-Spigot-b5a13e6-0d8350a]
at net.minecraft.server.v1_16_R2.MinecraftServer.w(MinecraftServer.java:887) ~[spigot.jar:git-Spigot-b5a13e6-0d8350a]
at net.minecraft.server.v1_16_R2.MinecraftServer.lambda$0(MinecraftServer.java:164) ~[spigot.jar:git-Spigot-b5a13e6-0d8350a]

[caoccao]

It seems to be a permission issue?

[Losin6450]

It only happens when using the node runtime, doesn't happen when using v8 runtime

[caoccao]

Well, I don't play Minecraft. Here are some ideas for your reference.

• Create a regular Java app with the same code, deploy that app to the same env to see if things break.
• Call File API in Java to see if it works.

[AsyncProxy]

使用节点实例时，java.io.File 类不起作用

If you write Spigot/Fabric/Forge plugins or mods, you can embed the Rhino engine, otherwise the plugins will be very large, and my suggestion is to use them more widely for embedded apps.

[AsyncProxy]

好吧，我不玩 Minecraft。以下是一些想法供您参考。

• 使用相同的代码创建一个常规的 Java 应用程序，将该应用程序部署到同一个环境，看看是否有问题。
• 在 Java 中调用 API 以查看它是否有效。File

Pls what happened to the problem that the engine of 3.1.2 does not work, I still can't run, no code has been changed, 3.1.1 is working normally.

[Losin6450]

after alot of trial and error the issue seems to come from the setResourceName method on the executor

[caoccao]

You may workaround it if it causes issues at your end. Please refer to this commit for detail.

[caoccao]

It's now surrounded by a try-catch clause so that that error can be omitted and logged.