Why does an error occur when compiling a program using fragments?

Question

Android

I created a trial program using a fragment, but when I run it, it gives an error

with other programs, this did not happen.
File MainActivity.java

package com.example.redry.fragment;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
public class MainActivity extends FragmentActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

activity_main.xml

<?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=".MainActivity">
    <fragment
        android:name="com.example.redry.fragment.Fragment1"
        android:id="@+id/frag"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:layout="@layout/fragment_fragment1">
    </fragment>
</android.support.constraint.ConstraintLayout>

Fragment1.java

package com.example.redry.fragment;
import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class Fragment1 extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View viewHierarchy = inflater.inflate(R.layout.fragment_fragment1, container, false);
        return viewHierarchy;
    }
}

fragment_fragment1.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/colorAccent"
    tools:context=".Fragment1">
    <!-- TODO: Update blank fragment layout -->
</FrameLayout>

I'm just learning android, please help