Difference between List vs Set in Java code of your Android App?

As shown in this video, the main difference are:

Set:

• every element is unique
• not ordered

List:

• can repeat the same element
• ordered

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Complete source code and other details:

package com.programmerworld.listvsset;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class MainActivity extends AppCompatActivity {

    private TextView textViewSet, textViewList;

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

        textViewList = findViewById(R.id.textViewList);
        textViewSet = findViewById(R.id.textViewSet);

    }


    public void buttonDisplay(View view){

        Set<String> stringsSet = new HashSet<>();

        stringsSet.add("Paris");
        stringsSet.add("Tokyo");
        stringsSet.add("Beijing");
        stringsSet.add("Seoul");
        stringsSet.add("Tokyo");

        textViewSet.setText(stringsSet.toString());

        List<String> stringsList = new ArrayList<>();

        stringsList.add("Paris");
        stringsList.add("Tokyo");
        stringsList.add("Beijing");
        stringsList.add("Seoul");
        stringsList.add("Tokyo");

        textViewList.setText(stringsList.toString());
    }
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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">

    <TextView
        android:id="@+id/textViewSet"
        android:layout_width="290dp"
        android:layout_height="175dp"
        android:text="Display Set"
        android:textSize="24sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.495"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.028" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="156dp"
        android:layout_marginTop="36dp"
        android:onClick="buttonDisplay"
        android:text="Display"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textViewList" />

    <TextView
        android:id="@+id/textViewList"
        android:layout_width="289dp"
        android:layout_height="159dp"
        android:layout_marginStart="60dp"
        android:layout_marginTop="32dp"
        android:text="Display List"
        android:textSize="24sp"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textViewSet" />

</androidx.constraintlayout.widget.ConstraintLayout>

With Duplicate entry of “Tokyo”

Without any duplicate entry: