Android Text view set message

JAVA FILE

package com.example.viraj.blog_1_textview;
import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.widget.TextView;
public class MainActivity extends AppCompatActivity {private TextView t1;
    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        t1=(TextView)findViewById(R.id.id_text);
        t1.setText("HELLO WORLD TEXT VIEW SET SUCESSFULLY");
    }
}

XML FILE

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.viraj.blog_1_textview.MainActivity">

    <TextView
        android:id="@+id/id_text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>