帮我生成一段完整Android代码，运用动态fragment使用四个按钮来切换我的NAME（祝杭杰）,AGE（21）,STUDENT ID（2020329621145）,和HOBBY（rap）

以下是可以实现您所说功能的完整Android代码：

MainActivity.java

import android.os.Bundle;
import android.view.View;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentTransaction;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private FragmentManager fragmentManager;
    private FragmentTransaction fragmentTransaction;
    private NameFragment nameFragment;
    private AgeFragment ageFragment;
    private StudentIdFragment studentIdFragment;
    private HobbyFragment hobbyFragment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        fragmentManager = getSupportFragmentManager();

        // 初始化四个Fragment
        nameFragment = new NameFragment();
        ageFragment = new AgeFragment();
        studentIdFragment = new StudentIdFragment();
        hobbyFragment = new HobbyFragment();

        // 设置四个按钮的点击事件
        findViewById(R.id.btn_name).setOnClickListener(this);
        findViewById(R.id.btn_age).setOnClickListener(this);
        findViewById(R.id.btn_student_id).setOnClickListener(this);
        findViewById(R.id.btn_hobby).setOnClickListener(this);

        // 默认显示NameFragment
        fragmentTransaction = fragmentManager.beginTransaction();
        fragmentTransaction.replace(R.id.fragment_container, nameFragment).commit();
    }

    @Override
    public void onClick(View v) {
        fragmentTransaction = fragmentManager.beginTransaction();
        switch (v.getId()) {
            case R.id.btn_name:
                fragmentTransaction.replace(R.id.fragment_container, nameFragment).commit();
                break;
            case R.id.btn_age:
                fragmentTransaction.replace(R.id.fragment_container, ageFragment).commit();
                break;
            case R.id.btn_student_id:
                fragmentTransaction.replace(R.id.fragment_container, studentIdFragment).commit();
                break;
            case R.id.btn_hobby:
                fragmentTransaction.replace(R.id.fragment_container, hobbyFragment).commit();
                break;
        }
    }
}

NameFragment.java

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.fragment.app.Fragment;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

public class NameFragment extends Fragment {

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_name, container, false);
        return view;
    }
}

AgeFragment.java

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.fragment.app.Fragment;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

public class AgeFragment extends Fragment {

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_age, container, false);
        return view;
    }
}

StudentIdFragment.java

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.fragment.app.Fragment;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

public class StudentIdFragment extends Fragment {

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_student_id, container, false);
        return view;
    }
}

HobbyFragment.java

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.fragment.app.Fragment;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

public class HobbyFragment extends Fragment {

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_hobby, container, false);
        return view;
    }
}

activity_main.xml

<FrameLayout
    android:id="@+id/fragment_container"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:gravity="center">

    <Button
        android:id="@+id/btn_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Name" />

    <Button
        android:id="@+id/btn_age"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Age" />

    <Button
        android:id="@+id/btn_student_id"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Student ID" />

    <Button
        android:id="@+id/btn_hobby"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hobby" />

</LinearLayout>

fragment_name.xml

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="祝杭杰" />

fragment_age.xml

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="21" />

fragment_student_id.xml

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="2020329621145" />

fragment_hobby.xml

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="rap" />