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error: class, interface, or enum expected on MainActivity.java

I'm trying to compile an app that utilizes Expo on Android Studio, however, every time I try I get the following error message:
\android\app\src\main\java\com\profileid\MainActivity.java:2: error: class, interface, or enum expected
package com.projectname;
I just upgraded to Expo SDK 43 and migrated from react-native-unimodules.
My MainActivity.java looks like this:
import expo.modules.ReactActivityDelegateWrapper;
package com.projectname;
import android.os.Bundle;
import com.facebook.react.ReactActivity;
import com.facebook.react.ReactActivityDelegate;
import com.facebook.react.ReactRootView;
import com.swmansion.gesturehandler.react.RNGestureHandlerEnabledRootView;
import expo.modules.splashscreen.singletons.SplashScreen;
import expo.modules.splashscreen.SplashScreenImageResizeMode;
public class MainActivity extends ReactActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// SplashScreen.show(...) has to be called after super.onCreate(...)
// Below line is handled by '#expo/configure-splash-screen' command and it's discouraged to modify it manually
SplashScreen.show(this, SplashScreenImageResizeMode.CONTAIN, ReactRootView.class, false);
}
/**
* Returns the name of the main component registered from JavaScript.
* This is used to schedule rendering of the component.
*/
#Override
protected String getMainComponentName() {
return "main";
}
#Override
protected ReactActivityDelegate createReactActivityDelegate() {
return new ReactActivityDelegateWrapper(this, new ReactActivityDelegate(this, getMainComponentName()) {
#Override
protected ReactRootView createRootView() {
return new RNGestureHandlerEnabledRootView(MainActivity.this);
}
});
}
}

Your first import statement and the package statement are out of order. The package statement must be the very first line of your file:
package com.projectname;
import android.os.Bundle;
import com.facebook.react.ReactActivity;
import com.facebook.react.ReactActivityDelegate;
import com.facebook.react.ReactRootView;
import com.swmansion.gesturehandler.react.RNGestureHandlerEnabledRootView;
import expo.modules.ReactActivityDelegateWrapper;
import expo.modules.splashscreen.singletons.SplashScreen;
import expo.modules.splashscreen.SplashScreenImageResizeMode;

Invalid Bukkit command | YML Error catch with valid YML

So I have double and triple checked my YML and ran it through a validator. My plugins load up fine, I can create a hello world command within my Main class that works. However upon using a second .java file with a second command it continuously displays my YML usage text.
Main.java
package lordfluffyjr.TarrenCraft.jEssentialsX.commandSrc;
import java.util.logging.Logger;
import org.bukkit.Bukkit;
import org.bukkit.event.Listener;
import org.bukkit.plugin.PluginManager;
import org.bukkit.plugin.java.JavaPlugin;
public class Main extends JavaPlugin implements Listener { //Extending JavaPlugin so that Bukkit
knows its the main class
//Housekeeping
Logger jEssentialsXLogger = Bukkit.getLogger();
#Override
public void onEnable(){// Where plugins will be loaded.
PluginManager manager = getServer().getPluginManager();
manager.registerEvents(this, this);
Bukkit.getServer().getConsoleSender().sendMessage("jEssentialsX has been enabled!");
//Enable FAQ
manager.registerEvents(new Faq(), this);
Bukkit.getServer().getConsoleSender().sendMessage("FAQ has been enabled!");
}
#Override
public void onDisable(){// Where plugins will be disabled.
jEssentialsXLogger.info("Test 1 has been disabled!");
jEssentialsXLogger.severe("Test 1 has an error and has not loaded.");
}
}
Faq.java
package lordfluffyjr.TarrenCraft.jEssentialsX.commandSrc;
import org.bukkit.command.Command;
import org.bukkit.command.CommandExecutor;
import org.bukkit.command.CommandSender;
import org.bukkit.event.Listener;
public class Faq implements Listener, CommandExecutor{
public boolean onCommand(CommandSender sender, Command cmd, String commandLabel, String[] args)
{
if (commandLabel.equalsIgnoreCase("faq")) {
sender.sendMessage("Welcome to our FAQ!");
return true;
}
return false;
}
}
plugin.yml
main: lordfluffyjr.TarrenCraft.jEssentialsX.commandSrc.Main
name: jEssentialsX
version: 0.1
author: LordFluffyJr
api-version: 1.16
commands:
faq:
description: A list of our frequently asked questions plugin description!
usage: Syntax error! Use [/faq <topic> <page number>]

You're not registering the Faq class as the command executor. You need to set it with
Bukkit.getPluginCommand("faq").setExecutor(- Faq class instance-);

" must be caught or declared to be thrown" in react native when using NativeModules

I want to build a native module to react-native that reboot device. I find this Turn off device programmatically in java. It works alone in android studio but when I try to use it in a native module I got the bellow error
https://pasteboard.co/IztJ6ll.jpg
C:\Users\Ali\Desktop\Android\ReactNative\ReactNativeTest\android\app\src\main\ja
va\com\reactnativetest\ToastModule.java:42: error: unreported exception IOExcept
ion; must be caught or declared to be thrown
Process proc = Runtime.getRuntime().exec(new String[] { "su", "-c", "reboot"
});
^
C:\Users\Ali\Desktop\Android\ReactNative\ReactNativeTest\android\app\src\main\ja
va\com\reactnativetest\ToastModule.java:43: error: unreported exception Interrup
tedException; must be caught or declared to be thrown
proc.waitFor();
^
2 errors
> Task :app:compileDebugJavaWithJavac FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:compileDebugJavaWithJavac'.
> Compilation failed; see the compiler error output for details.
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug
option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 9s
57 actionable tasks: 1 executed, 56 up-to-date
error Could not install the app on the device, read the error above for details.
Make sure you have an Android emulator running or a device connected and have
set up your Android development environment:
https://facebook.github.io/react-native/docs/getting-started.html
error Command failed: gradlew.bat app:installDebug. Run CLI with --verbose flag
for more details.
this is my native module:
package com.reactnativetest;
import android.widget.Toast;
import com.facebook.react.bridge.NativeModule;
import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import java.util.Map;
import java.util.HashMap;
import java.util.*;
import java.io.*;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.view.View.OnClickListener;
public class ToastModule extends ReactContextBaseJavaModule {
private static final String DURATION_SHORT_KEY = "SHORT";
private static final String DURATION_LONG_KEY = "LONG";
public ToastModule(ReactApplicationContext reactContext) {
super(reactContext);
}
#Override
public String getName() {
return "ToastExample";
}
#Override
public Map<String, Object> getConstants() {
final Map<String, Object> constants = new HashMap<>();
constants.put(DURATION_SHORT_KEY, Toast.LENGTH_SHORT);
constants.put(DURATION_LONG_KEY, Toast.LENGTH_LONG);
return constants;
}
#ReactMethod
public void show(String message, int duration) {
Toast.makeText(getReactApplicationContext(), message, duration).show();
Process proc = Runtime.getRuntime().exec(new String[] { "su", "-c", "reboot" });
proc.waitFor();
}
}

it is right there in the logs:
C:\Users\Ali\Desktop\Android\ReactNative\ReactNativeTest\android\app\src\main\ja
va\com\reactnativetest\ToastModule.java:43: error: unreported
exception InterruptedException; must be caught or declared to be
thrown
proc.waitFor();
proc.waitFor() throws an exception. You should either surround it with try-catch, or declare in the method signature throws InterruptedException and handle it elsewhere

React Native: error: cannot find symbol > new AppCenterReactNativeAnalyticsPackage(MainApplication.this

I was getting a successful build with android in React Native until I added these:
"appcenter-analytics": "2.1.0",
"appcenter-crashes": "2.1.0",
I am on:
"react": "16.8.6",
"react-native": "0.60.4",
The error is:
Error: Command failed: ./gradlew app:installDebug
-PreactNativeDevServerPort=8081 Note: /Users/danale/Projects/NFIBEngage/node_modules/react-native-sentry/android/src/main/java/io/sentry/RNSentryModule.java
uses or overrides a deprecated API. Note: Recompile with
-Xlint:deprecation for details. Note: Some input files use unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for
details.
/Users/danale/Projects/NFIBEngage/android/app/build/generated/rncli/src/main/java/com/facebook/react/PackageList.java:60:
error: cannot find symbol
new AppCenterReactNativeAnalyticsPackage(MainApplication.this, getResources().getString(R.string.appCenterAnalytics_whenToEnableAnalytics)),
^ symbol: class MainApplication location: class PackageList
/Users/danale/Projects/NFIBEngage/android/app/build/generated/rncli/src/main/java/com/facebook/react/PackageList.java:60:
error: cannot find symbol
new AppCenterReactNativeAnalyticsPackage(MainApplication.this, getResources().getString(R.string.appCenterAnalytics_whenToEnableAnalytics)),
^ symbol: variable appCenterAnalytics_whenToEnableAnalytics
location: class string
/Users/danale/Projects/NFIBEngage/android/app/build/generated/rncli/src/main/java/com/facebook/react/PackageList.java:61:
error: cannot find symbol
new AppCenterReactNativeCrashesPackage(MainApplication.this, getResources().getString(R.string.appCenterCrashes_whenToSendCrashes)),
^ symbol: class MainApplication location: class PackageList
/Users/danale/Projects/NFIBEngage/android/app/build/generated/rncli/src/main/java/com/facebook/react/PackageList.java:61:
error: cannot find symbol
new AppCenterReactNativeCrashesPackage(MainApplication.this, getResources().getString(R.string.appCenterCrashes_whenToSendCrashes)),
^ symbol: variable appCenterCrashes_whenToSendCrashes location:
class string 4 errors
FAILURE: Build failed with an exception.
What went wrong: Execution failed for task ':app:compileDebugJavaWithJavac'.
Compilation failed; see the compiler error output for details.
Apparently there is this android/app/build/generated/rncli/src/main/java/com/facebook/react/PackageList.java file that did not exist with the legacy version of this application:
package com.facebook.react;
import android.app.Application;
import android.content.Context;
import android.content.res.Resources;
import com.facebook.react.ReactPackage;
import com.facebook.react.shell.MainReactPackage;
import java.util.Arrays;
import java.util.ArrayList;
import com.nfibengage.BuildConfig;
import com.nfibengage.R;
// #react-native-community/async-storage
import com.reactnativecommunity.asyncstorage.AsyncStoragePackage;
// appcenter-analytics
import com.microsoft.appcenter.reactnative.analytics.AppCenterReactNativeAnalyticsPackage;
// appcenter-crashes
import com.microsoft.appcenter.reactnative.crashes.AppCenterReactNativeCrashesPackage;
// react-native-sentry
import io.sentry.RNSentryPackage;
// react-native-splash-screen
import org.devio.rn.splashscreen.SplashScreenReactPackage;
public class PackageList {
private Application application;
private ReactNativeHost reactNativeHost;
public PackageList(ReactNativeHost reactNativeHost) {
this.reactNativeHost = reactNativeHost;
}
public PackageList(Application application) {
this.reactNativeHost = null;
this.application = application;
}
private ReactNativeHost getReactNativeHost() {
return this.reactNativeHost;
}
private Resources getResources() {
return this.getApplication().getResources();
}
private Application getApplication() {
if (this.reactNativeHost == null) return this.application;
return this.reactNativeHost.getApplication();
}
private Context getApplicationContext() {
return this.getApplication().getApplicationContext();
}
public ArrayList<ReactPackage> getPackages() {
return new ArrayList<>(Arrays.<ReactPackage>asList(
new MainReactPackage(),
new AsyncStoragePackage(),
new AppCenterReactNativeAnalyticsPackage(MainApplication.this, getResources().getString(R.string.appCenterAnalytics_whenToEnableAnalytics)),
new AppCenterReactNativeCrashesPackage(MainApplication.this, getResources().getString(R.string.appCenterCrashes_whenToSendCrashes)),
new RNSentryPackage(),
new SplashScreenReactPackage()
));
}
}
The MainApplication.java file is inside of android/main/java/com/nfibengage/MainApplication.java:
package com.nfibengage;
import android.app.Application;
import android.util.Log;
import com.facebook.react.PackageList;
import com.facebook.hermes.reactexecutor.HermesExecutorFactory;
import com.facebook.react.bridge.JavaScriptExecutorFactory;
import com.facebook.react.ReactApplication;
import com.facebook.react.ReactNativeHost;
import com.facebook.react.ReactPackage;
import com.facebook.soloader.SoLoader;
import java.util.List;
public class MainApplication extends Application implements ReactApplication {
private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {
#Override
public boolean getUseDeveloperSupport() {
return BuildConfig.DEBUG;
}
#Override
protected List<ReactPackage> getPackages() {
#SuppressWarnings("UnnecessaryLocalVariable")
List<ReactPackage> packages = new PackageList(this).getPackages();
// Packages that cannot be autolinked yet can be added manually here, for example:
// packages.add(new MyReactNativePackage());
return packages;
}
#Override
protected String getJSMainModuleName() {
return "index";
}
};
#Override
public ReactNativeHost getReactNativeHost() {
return mReactNativeHost;
}
#Override
public void onCreate() {
super.onCreate();
SoLoader.init(this, /* native exopackage */ false);
}
}
I tried importing it into PackageList.java like so:
import com.nfibengage.MainApplication;
but I continue to get the same error. If anyone can walk me through where did this PackageList.java file come from and how do I get this working again short of just completely removing appcenter-analytics and appcenter-crashes.

Please make sure your installation order is the same as the following.
Add the App Center SDK modules
npm install appcenter appcenter-analytics appcenter-crashes --save-exact
or
yarn add appcenter appcenter-analytics appcenter-crashes --exact
Integrate the SDK automatically
react-native link appcenter
react-native link appcenter-analytics
react-native link appcenter-crashes
App Center SDK does not set up mocks automatically for App Center modules during the linking process. If you are using Jest test framework in your application and experience errors caused by the App Center SDK while running tests with Jest, add the following to the jest section of package.json file (include only modules in use):
"setupFiles": [
"<rootDir>/node_modules/appcenter/test/AppCenterMock.js",
"<rootDir>/node_modules/appcenter-analytics/test/AppCenterAnalyticsMock.js",
"<rootDir>/node_modules/appcenter-crashes/test/AppCenterCrashesMock.js",
"<rootDir>/node_modules/appcenter-push/test/AppCenterPushMock.js"
]
Edit the project's android/app/src/main/assets/appcenter-config.json and replace the YOUR_APP_SECRET placeholder value with your App Center project's application secret.

do one think only
goto your folder structure.
2.Add a file yarn-error.log
there will not be any problem your project will start well.

using gradle, error: cannot find symbol #Test

I am trying to build the tests using gradle in the project.
On building the tests, I am getting error ->
:compileTestJava/home/vibhcool/Documents/github/loklak_server/test/org/loklak/harvester/TwitterScraperTest.java:28: error: cannot find symbol
#TEST
^
symbol: class TEST
location: class TwitterScraperTest
1 error
FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':compileTestJava'.
The file in which I am getting error ->
package org.loklak.harvester;
import java.io.File;
import java.io.IOException;
import org.junit.After;
import org.junit.Before;
import org.loklak.harvester.TwitterScraper;
import org.junit.Test;
import static org.junit.Assert.assertEquals;
public class TwitterScraperTest {
#TEST
public void test_prepareSearchURL() {
String url;
String[] query = {"q1", "q2", "q3", };
String[] out_url = {"url1", "url2", "url3"};
for (int i = 0; i < query.length; i++) {
url = TwitterScraper.prepareSearchURL(query[i]);
assertEquals(url, out_url[i]);
}
}
}
When I comment #TEST in the file, gradle successfully builds the tests.
I have googled a lot but, not able to get the error.
I am using junit 4.10

It should be :
#Test
public void test_prepareSearchURL() {
...
}
and not
#TEST
public void test_prepareSearchURL() {
..
}
You can take a look on how to get started with Junit here.