问题[java]

为什么此代码会加密除俄语字符之外的所有字符？

这里我搜索并替换字母表中的字符：

private void encrypting(Path sourcePath, Path resultPath, List<Character> alphabet, int key) {
    try (FileChannel source = FileChannel.open(sourcePath, StandardOpenOption.READ);
         FileChannel result = FileChannel.open(resultPath, StandardOpenOption.WRITE)) {
        ByteBuffer buffer = ByteBuffer.allocate(1024);
        while (source.read(buffer) != -1) {
            buffer.flip();
            while (buffer.hasRemaining()) {
                byte b = buffer.get();
                char c = (char) b;
                int index = alphabet.indexOf(c);
                if (index != -1) {
                    int newIndex = Math.floorMod(index + key, alphabet.size());
                    char encrypted = alphabet.get(newIndex);
                    result.write(ByteBuffer.wrap(new byte[]{(byte) encrypted}));
                } else {
                    result.write(ByteBuffer.wrap(new byte[]{(byte) c}));
                }
            }
            buffer.clear();
        }
    } catch (IOException e) {
        throw new RuntimeException(e);
    }
}

这里将俄文字母添加到字母表中：

for (char i = 'А'; i <= 'Я'; i++) {
    alphabet.add(i);
}
for (char i = 'а'; i <= 'я'; i++) {
    alphabet.add(i);
}

需要加密的原始字符串：

Бородино Borodino 1234567890(),?>

加密结果：

Бородино%Gtwtinst%6789:;<=>5-.1ED

为什么此代码会加密除俄文字母之外的所有字符？

简介：Java 中有一个复杂的项目，目前正在使用 Jetpack Compose（特别是 Composable 函数）在 Kotlin 中进行模块化重写。在不同活动之间传递额外参数的旧实现是典型的（通过意图）：

主活动（java）：

    button.setOnClickListener(v -> {
                startActivityForResult(new Intent(MainActivity.this, SecondActivity.class), 1234);
            });
    
    .....
    
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == 1234 && resultCode == RESULT_OK) {
                //TODO Здесь какие-то действия (например получение инта)
        }
    }

SecondActivity（java）：

int intPosition = 7
    backButton.setOnClickListener(view -> {
       Intent intent = new Intent();
       intent.putExtra("result", intPosition);
       setResult(RESULT_OK, intent);
       finish();
    });

但是，过渡到 Composable 的新实现意味着使用 BackHandler 和 OnBackPressedDispatcher，下面是示例：

第二项活动（带有@Composable的kotlin）：

class SecondActivity : ComponentActivity() {
        override fun onCreate(savedInstanceState: Bundle?) {
            super.onCreate(savedInstanceState)
            setContent {
                MaterialTheme {
                    PatternPager()
                }
            }
        }
    }
        
    @Composable
    fun PatternPager() {
    val onBackPressedDispatcher = LocalOnBackPressedDispatcherOwner.current?.onBackPressedDispatcher
    val onBackToActivity = {
        println("back pressed")
        scope.launch {
            awaitFrame()
            onBackPressedDispatcher?.onBackPressed()
        }
    }
        Box(...) {
            Row(...) {
                ...
                Button(
                    onClick = {
                        scope.launch {
                            //TODO Здесь логика перехода
                            onBackToActivity()
                        }
                    }
                }
            }

问题是，需要在 MainActivity.java 文件中做哪些更改，才能在类似于 onActivityResult 的 PatternPager() 函数中接受来自 @Composable 的更改，以及如何将来自 @Composable 的更改发送到 java。

转换已经实现，您只需要传递额外内容。这个任务并不容易，因为 MainActivity 需要以 java 格式保存。

我向那些遇到过项目从 Java 到 Kotlin 部分迁移的人寻求帮助和建议/假设。

如何从 Java 类中的另一个包调用 Kotlin 函数？

有一个包fcmpushnotificationshttpv1，其中有一个用 Kotlin 实现的类ChatViewModel.kt。
还有一个dem.corp.androidmessenger包含类的包NewChatFragment。我想从类中另一个包中的类中NewChatFragment调用一个函数。sendMessageChatViewModel

为此我编写了以下代码：

//ymy NEW test
new  fcmpushnotificationshttpv1.ChatViewModel.ChatViewModel();
fcmpushnotificationshttpv1.sendMessage(true);

但是我收到一个编译错误：

C:\androidSDK\AndroidStudioProjects\AndroidMessenger-main\app\src\main\java\dem\corp\androidmessenger\bottomnav\new_chat\NewChatFragment.java:56: error: package fcmpushnotificationshttpv1.ChatViewModel does not exist
new fcmpushnotificationshttpv1.ChatViewModel.ChatViewModel();

项目结构及包清单如下：

为什么看不到这个包？
它甚至没有帮助//import com.plcoding.fcmpushnotificationshttpv1.ChatViewModel;

也没有看到SDK包。

我按照 Nowhere Man 所说的写了，但是出现了错误：

C:\androidSDK\AndroidStudioProjects\AndroidMessenger-main\app\src\main\java\dem\corp\androidmessenger\bottomnav\new_chat\NewChatFragment.java:30: error: package fcmpushnotificationshttpv1 does not exist
import fcmpushnotificationshttpv1.ChatViewModel;
^

以下是该文件的内容NewChatFragment.java：

package dem.corp.androidmessenger.bottomnav.new_chat;

import static androidx.fragment.app.FragmentManager.TAG;

import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.recyclerview.widget.DividerItemDecoration;
import androidx.recyclerview.widget.LinearLayoutManager;

import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
//import fcmpushnotificationshttpv1.ChatViewModel;
//import fcmpushnotificationshttpv1.ChatViewModel;

import java.util.ArrayList;

import dem.corp.androidmessenger.databinding.FragmentNewChatBinding;
import dem.corp.androidmessenger.users.User;
import dem.corp.androidmessenger.users.UsersAdapter;
//import fcmpushnotificationshttpv1.ChatViewModel;
//import fcmpushnotificationshttpv1.ChatViewModel;
//import fcmpushnotificationshttpv1.ChatViewModel;
//import fcmpushnotificationshttpv1.ChatViewModel;
//import fcmpushnotificationshttpv1.ChatViewModel;

public class NewChatFragment extends Fragment {
    private FragmentNewChatBinding binding;

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        binding = FragmentNewChatBinding.inflate(inflater, container, false);

        loadUsers();

        return binding.getRoot();
    }

    private void loadUsers(){
        ArrayList<User> users = new ArrayList<User>();
        FirebaseDatabase.getInstance().getReference().child("Users").addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {
                for (DataSnapshot userSnapshot : snapshot.getChildren()){
                    if (userSnapshot.getKey().equals(FirebaseAuth.getInstance().getCurrentUser().getUid())){
                        continue;
                    }


                    //ymy NEW test
// вызов конструктора класса ChatViewModel
                    // вызов конструктора класса ChatViewModel
                    ChatViewModel chatViewModel = new fcmpushnotificationshttpv1.ChatViewModel();

// вызов package-level функции 
                    fcmpushnotificationshttpv1.ChatViewModel.sendMessage(true);

// вызов package-level функции
                    fcmpushnotificationshttpv1.ChatViewModel.sendMessage(true);
                   // ChatViewModel.sendMessage(true);
                 //   new fcmpushnotificationshttpv1.ChatViewModel();
                  //  fcmpushnotificationshttpv1.ChatViewModel.class.

                    //my test OK
                   //показывает flase у всех юзеров String username = String.valueOf(userSnapshot.getKey().equals(FirebaseAuth.getInstance().getCurrentUser().getUid()));
                    String username = userSnapshot.child("username").getValue().toString();
                    Log.w(TAG, "Error getting documents. 2222 username=" + username);


                    String uid = userSnapshot.getKey();
                    Log.w(TAG, "Error getting documents. 2222 uid=" + uid);

                    //String username = Objects.requireNonNull(userSnapshot.child("username").getValue()).toString();
                    String profileImage = String.valueOf(userSnapshot.child("profileImage").getValue());

                    users.add(new User(uid, username, profileImage));
                }

                binding.usersRv.setLayoutManager(new LinearLayoutManager(getContext()));
                binding.usersRv.addItemDecoration(new DividerItemDecoration(getContext(), DividerItemDecoration.VERTICAL));
                binding.usersRv.setAdapter(new UsersAdapter(users));
            }

            @Override
            public void onCancelled(@NonNull DatabaseError error) {

            }
        });
    }
}

以下是该文件的内容ChatViewModel.kt：

@file:JvmName("ChatViewModel")
package fcmpushnotificationshttpv1

import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.setValue
import androidx.lifecycle.ViewModel
import androidx.lifecycle.viewModelScope
import com.google.firebase.ktx.Firebase
import com.google.firebase.messaging.ktx.messaging
import kotlinx.coroutines.launch
import kotlinx.coroutines.tasks.await
import retrofit2.HttpException
import retrofit2.Retrofit
import retrofit2.converter.moshi.MoshiConverterFactory
import retrofit2.create
import java.io.IOException


class ChatViewModel: ViewModel() {

    var state by mutableStateOf(ChatState())
        private set

    private val api: FcmApi = Retrofit.Builder()
      //  .baseUrl("http://10.0.2.2:8084/")
        .baseUrl("http://109.195.103.21:8084/")
        .addConverterFactory(MoshiConverterFactory.create())
        .build()
        .create()

    init {
        viewModelScope.launch {
            Firebase.messaging.subscribeToTopic("chat").await()
        }
    }

    fun onRemoteTokenChange(newToken: String) {
        state = state.copy(
            remoteToken = newToken
        )
    }

    fun onSubmitRemoteToken() {
        state = state.copy(
            isEnteringToken = false
        )
    }

    fun onMessageChange(message: String) {
        state = state.copy(
            messageText = message
        )
    }

    fun sendMessage(isBroadcast: Boolean) {
        viewModelScope.launch {
            val messageDto = SendMessageDto(
                to = if(isBroadcast) null else state.remoteToken,
                notification = NotificationBody(
                    title = "New message!",
                    body = state.messageText
                )
            )

            try {
                if(isBroadcast) {
                    api.broadcast(messageDto)
                } else {
                    api.sendMessage(messageDto)
                }

                state = state.copy(
                    messageText = ""
                )
            } catch(e: HttpException) {
                e.printStackTrace()
            } catch(e: IOException) {
                e.printStackTrace()
            }
        }
    }
}

我正在尝试从 Firebase 控制台发送推送消息，但没有任何消息发送成功。

有这样一段代码：

package dem.corp.androidmessenger;

import static androidx.fragment.app.FragmentManager.TAG;

import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.messaging.FirebaseMessaging;

import java.util.HashMap;
import java.util.Map;

import dem.corp.androidmessenger.bottomnav.chats.ChatsFragment;
import dem.corp.androidmessenger.bottomnav.new_chat.NewChatFragment;
import dem.corp.androidmessenger.bottomnav.profile.ProfileFragment;
import dem.corp.androidmessenger.databinding.ActivityMainBinding;

public class MainActivity extends AppCompatActivity {

    private ActivityMainBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = ActivityMainBinding.inflate(getLayoutInflater());
        setContentView(binding.getRoot());

//fcm
        FirebaseMessaging.getInstance().getToken()
                .addOnCompleteListener(new OnCompleteListener<String>() {
                    @Override
                    public void onComplete(@NonNull Task<String> task) {
                        if (!task.isSuccessful()) {
                            Log.w(TAG, "Fetching FCM registration token failed", task.getException());
                            return;
                        }
                        // Get new FCM registration token
                        String token = task.getResult();
                        // Log and toast
                        //String msg = getString(R.string.msg_token_fmt, token);
                        Log.d(TAG, "222 token = " + token);
                        Toast.makeText(MainActivity.this, token, Toast.LENGTH_SHORT).show();
                    }
                });  //END FCM


        if (FirebaseAuth.getInstance().getCurrentUser()==null){
            startActivity(new Intent(MainActivity.this, LoginActivity.class));
        }

        getSupportFragmentManager().beginTransaction().replace(binding.fragmentContainer.getId(), new ChatsFragment()).commit();
        binding.bottomNav.setSelectedItemId(R.id.chats);

        Map<Integer, Fragment> fragmentMap = new HashMap<>();
        fragmentMap.put(R.id.chats, new ChatsFragment());
        fragmentMap.put(R.id.new_chat, new NewChatFragment());
        fragmentMap.put(R.id.profile, new ProfileFragment());

        binding.bottomNav.setOnItemSelectedListener(item -> {
            Fragment fragment = fragmentMap.get(item.getItemId());

            getSupportFragmentManager().beginTransaction().replace(binding.fragmentContainer.getId(), fragment).commit();

            return true;
        });
    }
}

从此代码中我获得一个令牌并将该令牌输入到 Firebase 控制台。

我没有在清单中配置任何东西。告诉我，为什么我收不到来自 FCM 的消息？

在 LogCat 中它说：

  ndroidmessenger         dem.corp.androidmessenger            W  Accessing hidden method Landroid/os/WorkSource;->add(I)Z (unsupported,test-api, reflection, allowed)
2025-02-01 12:53:26.688  6595-6820  ndroidmessenger         dem.corp.androidmessenger            W  Accessing hidden method Landroid/os/WorkSource;->add(ILjava/lang/String;)Z (unsupported,test-api, reflection, allowed)
2025-02-01 12:53:26.688  6595-6820  ndroidmessenger         dem.corp.androidmessenger            W  Accessing hidden method Landroid/os/WorkSource;->get(I)I (unsupported, reflection, allowed)
2025-02-01 12:53:26.688  6595-6820  ndroidmessenger         dem.corp.androidmessenger            W  Accessing hidden method Landroid/os/WorkSource;->getName(I)Ljava/lang/String; (unsupported, reflection, allowed)
2025-02-01 12:53:26.718  6595-6824  FirebaseMessaging       dem.corp.androidmessenger            W  Missing Default Notification Channel metadata in AndroidManifest. Default value will be used.
2025-02-01 12:53:26.727  6595-6824  Compatibil...geReporter dem.corp.androidmessenger            D  Compat change id reported: 160794467; UID 10192; state: ENABLED

并且文件显示如下内容： Android Stdio 建议我使用管理器更改文件：我选中了所有框，但文件没有任何更改：

同时，我在宣言中补充了以下数据：

  <meta-data
        android:name="default_notification_channel_id"
        android:value="@string/default_notification_channel_id" />
    <meta-data
        android:name="com.google.firebase.messaging.default_notification_channel_id"
        android:value="high_importance_channel" />

救命，为什么我收不到 fcm 消息？

你能帮忙吗？在拆分（用逗号将字符串分成数组）时，会出现一些错误信息。以下是我尝试拆分成数组的变量 chatsStr 的内容：

chatsStr-ODqP1-1G1AtcwnrDVLk, ZqnkGaeyk3UkRLRJH8Qh1tQiF7d2

日志中显示的内容如下：

chatsIds[Ljava.lang.String;@86a42f3

激活码如下：

package dem.corp.androidmessenger.bottomnav.chats;

import static androidx.fragment.app.FragmentManager.TAG;

import androidx.fragment.app.Fragment;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.recyclerview.widget.LinearLayoutManager;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Objects;

import dem.corp.androidmessenger.chats.Chat;
import dem.corp.androidmessenger.chats.ChatsAdapter;
import dem.corp.androidmessenger.databinding.FragmentChatsBinding;
import dem.corp.androidmessenger.utils.ChatUtil;

public class ChatsFragment extends Fragment {
    private FragmentChatsBinding binding;

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        binding = FragmentChatsBinding.inflate(inflater, container, false);

        loadChats();

        return binding.getRoot();
    }

    @SuppressLint("RestrictedApi")
    private void loadChats(){

        Log.w(TAG, "Error getting documents. 222");
        ArrayList<Chat> chats = new ArrayList<>();

        String uid = Objects.requireNonNull(FirebaseAuth.getInstance().getCurrentUser()).getUid();
        Log.w(TAG, "Error getting documents. 222 uid =" + uid);
        FirebaseDatabase.getInstance().getReference().addListenerForSingleValueEvent(new ValueEventListener() {
            @SuppressLint("RestrictedApi")
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {
                String chatsStr = Objects.requireNonNull(snapshot.child("Users").child("ZqnkGaeyk3UkRLRJH8Qh1tQiF7d2").child("chats").getValue()).toString();
                Log.w(TAG, "Error getting documents. 2222 chatsStr" + chatsStr);

                String[] chatsIds = chatsStr.split(",");
                Log.w(TAG, "Error getting documents. 2222 chatsIds" + chatsIds);

                //ChatUtil.createChat("ZqnkGaeyk3UkRLRJH8Qh1tQiF7d2");
               // FirebaseDatabase.getInstance().getReference().child("Users").child("mdlfnx5Bo4dbpKOjwmUxaiyJzAY2")
                 //       .child("chats").setValue(chatsUpd);
                String uid = Objects.requireNonNull(FirebaseAuth.getInstance().getCurrentUser()).getUid();
                Log.w(TAG, "Error getting documents. 2222 chats uid=" + uid);
                HashMap<String, String> chatInfo = new HashMap<>();
                chatInfo.put("user1", uid);
                chatInfo.put("user2", "1Sx2FCTKDcdfjhztPtTbWgSxFZP2");

                String chatCurrentId = "ZqnkGaeyk3UkRLRJH8Qh1tQiF7d2";
               // String chatId = generateChatId(uid, user.uid);
                FirebaseDatabase.getInstance().getReference().child("Chats").child(chatCurrentId)
                        .setValue(chatInfo);

                if (chatsIds.length==0) return;

                for (String chatId : chatsIds){
                   // DataSnapshot chatSnapshot = snapshot.child("Chats").child(chatId);
                    DataSnapshot chatSnapshot = snapshot.child("Chats").child("ZqnkGaeyk3UkRLRJH8Qh1tQiF7d2");
                    String userId1 = Objects.requireNonNull(chatSnapshot.child("user1").getValue()).toString();
                    Log.w(TAG, "Error getting documents. 2222 userId1=" + userId1);
                    String userId2 = Objects.requireNonNull(chatSnapshot.child("user2").getValue()).toString();
                    Log.w(TAG, "Error getting documents. 2222 userId2=" + userId2);


                    String chatUserId = (uid.equals(userId1)) ? userId2 : userId1;
                    Log.w(TAG, "Error getting documents. 2222 chatUserId=" + chatUserId);
                    String chatName = Objects.requireNonNull(snapshot.child("Users").child(chatUserId).child("username").getValue()).toString();

                    Chat chat = new Chat(chatId, chatName, userId1, userId2);
                    chats.add(chat);
                }

                binding.chatsRv.setLayoutManager(new LinearLayoutManager(getContext()));
                binding.chatsRv.setAdapter(new ChatsAdapter(chats));
            }

            @Override
            public void onCancelled(@NonNull DatabaseError error) {
                Toast.makeText(getContext(), "Failed to get user chats", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

告诉我，发生什么事了？