使用Java编写表单数据的离线存储与同步功能

public class FormData {
    private String name;
    private int age;
    private String email;

    // 构造函数
    public FormData(String name, int age, String email) {
        this.name = name;
        this.age = age;
        this.email = email;
    }

    // Getter和Setter方法
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }
}

import androidx.room.Database;
import androidx.room.Room;
import androidx.room.RoomDatabase;
import android.content.Context;

@Database(entities = {FormData.class}, version = 1)
public abstract class AppDatabase extends RoomDatabase {
    private static AppDatabase INSTANCE;

    public abstract FormDataDao formDataDao();

    public static AppDatabase getInstance(Context context) {
        if (INSTANCE == null) {
            INSTANCE = Room.databaseBuilder(context.getApplicationContext(),
                    AppDatabase.class, "form-data-db").build();
        }
        return INSTANCE;
    }
}

import okhttp3.MediaType;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.RequestBody;
import okhttp3.Response;

public class SyncManager {
    private static final MediaType JSON = MediaType.parse("application/json; charset=utf-8");

    public static void syncFormData(FormData formData) throws IOException {
        OkHttpClient client = new OkHttpClient();
        String json = "{ "name": "" + formData.getName() +
                      "", "age": " + formData.getAge() +
                      ", "email": "" + formData.getEmail() + "" }";
        RequestBody requestBody = RequestBody.create(JSON, json);
        Request request = new Request.Builder()
                .url("http://example.com/api/formdata")
                .post(requestBody)
                .build();
        Response response = client.newCall(request).execute();
        if (response.isSuccessful()) {
            // 同步成功，可以删除本地存储的表单数据
            AppDatabase.getInstance(context).formDataDao().delete(formData);
        }
    }
}

import android.os.Bundle;
import android.view.View;
import androidx.appcompat.app.AppCompatActivity;

public class FormActivity extends AppCompatActivity {
    private EditText nameEditText;
    private EditText ageEditText;
    private EditText emailEditText;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_form);
        
        nameEditText = findViewById(R.id.edit_text_name);
        ageEditText = findViewById(R.id.edit_text_age);
        emailEditText = findViewById(R.id.edit_text_email);
        
        Button submitButton = findViewById(R.id.button_submit);
        submitButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String name = nameEditText.getText().toString();
                int age = Integer.parseInt(ageEditText.getText().toString());
                String email = emailEditText.getText().toString();
                
                FormData formData = new FormData(name, age, email);
                AppDatabase.getInstance(FormActivity.this).formDataDao().insert(formData);
                
                if (NetworkUtils.isNetworkConnected(FormActivity.this)) {
                    // 如果有网络连接，则立即进行同步
                    try {
                        SyncManager.syncFormData(formData);
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
        });
    }
}