如何查找默认的活动类名称？

import android.content.Context;
import android.content.pm.ActivityInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // 获取应用程序的上下文对象
        Context context = getApplicationContext();

        // 获取包管理器对象
        PackageManager packageManager = context.getPackageManager();

        try {
            // 获取应用程序的包信息
            PackageInfo packageInfo = packageManager.getPackageInfo(context.getPackageName(), PackageManager.GET_ACTIVITIES);

            // 获取活动信息列表
            ActivityInfo[] activities = packageInfo.activities;

            // 遍历活动信息列表，找到默认的活动类名称
            for (ActivityInfo activityInfo : activities) {
                if (activityInfo.launchMode == ActivityInfo.LAUNCHER) {
                    String defaultActivityName = activityInfo.name;
                    // 在这里可以使用默认的活动类名称进行后续操作
                    break;
                }
            }
        } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        }
    }
}