Android Atudio

public class MainActivity extends AppCompatActivity {
private TextView tv;
private ImageView iv;
public EditText name, username, email, number, password;
Button register;
FirebaseAuth mFirebaseAuth;
    @Override
    protected void onCreate(Bundle savedInstanceState) {

        mFirebaseAuth = FirebaseAuth.getInstance() ;
        email = findViewById(R.id.email);
        name = findViewById(R.id.name);
        username = findViewById(R.id.username);
        number = findViewById(R.id.number);
        password = findViewById(R.id.password);
      //  confirmpass = findViewById(R.id.confirmpass);
        register = findViewById(R.id.register);
        register.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v){
                String Email = email.getText().toString();
                String Name = name.getText().toString();
                String Uname = username.getText().toString().trim();
                String Num = number.getText().toString().trim();
                String Pwd = password.getText().toString().trim();
            //    String CPwd = confirmpass.getText().toString().trim();
                if(Email.isEmpty()) {
                email.setError("Please Enter Your Email");
                email.requestFocus();
                }
                else if(Name.isEmpty()){
                    name.setError("Please Enter Your Name");
                    name.requestFocus();
                }
                else if(Uname.isEmpty()){
                    username.setError("Please Enter an User Name");
                    username.requestFocus();
                }
                else if(Num.isEmpty()){
                    number.setError("Please Enter Your Contact Number");
                    number.requestFocus();
                }
                else if(Pwd.isEmpty()){
                    password.setError("Please Enter a Password");
                    password.requestFocus();
                }
             //   else if(CPwd.isEmpty()){
            //        confirmpass.setError("Please Confirm Your Password");
              //      confirmpass.requestFocus();
              //  }
                else if (Email.isEmpty() && Pwd.isEmpty()){
                    Toast.makeText(MainActivity.this,"Fields Are Empty!",Toast.LENGTH_SHORT).show();

                }
                else if (!(Email.isEmpty() && Pwd.isEmpty())){
                  mFirebaseAuth.createUserWithEmailAndPassword(Email, Pwd).addOnCompleteListener(MainActivity.this, new OnCompleteListener<AuthResult>() {
                      @Override
                      public void onComplete(@NonNull Task<AuthResult> task) {
                      if (!task.isSuccessful()){
                          Toast.makeText(MainActivity.this,"Sign Up Unsuccessful, Please Try Again",Toast.LENGTH_SHORT).show();
                      }else{
                          startActivity(new Intent(MainActivity.this,home.class));
                      }
                      }
                  });
                }
                else{
                    Toast.makeText(MainActivity.this,"Error Ocured!",Toast.LENGTH_SHORT).show();
                }
            }
        });




        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tv = (TextView) findViewById(R.id.tv);
        iv = (ImageView) findViewById(R.id.iv);
        Animation myanim = AnimationUtils.loadAnimation(this,R.anim.mytransition);
        tv.startAnimation(myanim);
        iv.startAnimation(myanim);
        final Intent i = new Intent(this,login.class);
        Thread timer =  new Thread(){
            public void run(){
                try{
                    sleep(3000);
                }
                catch (InterruptedException e){
                    e.printStackTrace();
                }
                finally {
                    startActivity(i);
                    finish();
                }
            }
        };
        timer.start();
    }
}