Firebase value set with one fetch

 1.Atoset child class

package abhiandroid.com.practice;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;

public class MainActivity extends AppCompatActivity {

    EditText editText1, editText2;
    Button button;

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

        editText1 = findViewById(R.id.editText1);
        editText2 = findViewById(R.id.editText2);
        button = findViewById(R.id.button);

// Write a message to the database



       button.setOnClickListener(new View.OnClickListener() {
           @Override
           public void onClick(View v) {

               FirebaseDatabase database = FirebaseDatabase.getInstance();
               DatabaseReference myRef = database.getReference();

               String name = editText1.getText().toString();
               String address = editText2.getText().toString();

               Model model = new Model(name,address);

               myRef.child(name).setValue(model);

            //   myRef.setValue(name);
               Toast.makeText(MainActivity.this,"hi"+ name, Toast.LENGTH_SHORT).show();



           }
       });




    }
}

2. model class because data Set purpose.

package abhiandroid.com.practice;

public class Model {
    String name, address;

    public String getName() {
        return name;
    }

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

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public Model(String name, String address) {
        this.name = name;
        this.address = address;


    }
}

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3.Direct data fetch

package abhiandroid.com.practice;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;

import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;

public class MainActivity4 extends AppCompatActivity {
    //direct data fetch

    FirebaseDatabase database;
    DatabaseReference myRef;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main4);

         database = FirebaseDatabase.getInstance();
         myRef  = database.getReference("Student");

// Read from the database
        myRef.child("s1").addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                // This method is called once with the initial value and again
                // whenever data at this location is updated.
                student Student = dataSnapshot.getValue(student.class);
                if(Student != null) {

                    String name = Student.name;



                    Log.d("tag", "Value is:" + name);
                }
            }

            @Override
            public void onCancelled(DatabaseError error) {

                // Failed to read value
              //  Log.w(TAG, "Failed to read value.", error.toException());
            }
        });



    }
}

4.student

package abhiandroid.com.practice;

public class student {

    public String name ;

    public student(){

    }

    public student(String name) {
        this.name = name;

    }
}

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