java - How to convert ArrayList to Array

MainActivity.java 
 package com.cfsuman.me.javaexamples;  import android.graphics.Color; import android.graphics.drawable.ColorDrawable; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.Window; import android.widget.RelativeLayout; import android.widget.TextView;  import java.util.ArrayList; import java.util.List;   public class MainActivity extends AppCompatActivity {      @Override     protected void onCreate(Bundle savedInstanceState) {         requestWindowFeature(Window.FEATURE_ACTION_BAR);         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          // Set background color for action kafetaria         getSupportActionBar().setBackgroundDrawable(new ColorDrawable(Color.RED));          // Get widget reference from XML layout         RelativeLayout rl = (RelativeLayout) findViewById(R.id.rl);         TextView tv = (TextView) findViewById(R.id.tv);          // Empty the TextView         tv.setText("");          // Initializing a new ArrayList         List<String> stringList = new ArrayList<>();         // Put some elements to it         stringList.add("Red");         stringList.add("Yellow");         stringList.add("Crimson");         stringList.add("Magenta");          // Iterate over the ArrayList         tv.setText(tv.getText() + "String list : ");         for(int i=0;i<stringList.size();i++){             tv.setText(tv.getText() + stringList.get(i) + ", ");         }          /*             Convert the ArrayList to an Array             Both array and list element data type is String             So, it will convert a String data type ArrayList to String Array         */         String[] stringArray = stringList.toArray(new String[stringList.size()]);          // Iterate over the converted String Array         tv.setText(tv.getText() + "\nString array (converted) : ");         for(int i=0;i<stringArray.length;i++){             tv.setText(tv.getText() + stringArray[i] + ", ");         }          // Initialize an Integer ArrayList         List<Integer> integerList = new ArrayList<>();         // Put some number to the list         integerList.add(1);         integerList.add(2);         integerList.add(3);         integerList.add(4);         integerList.add(5);          // Iterate over the Integer ArrayList         tv.setText(tv.getText() + "\n\nInteger list : ");         for(int i=0;i<integerList.size();i++){             tv.setText(tv.getText() + "" + integerList.get(i) + ", ");         }          // Convert Integer ArrayList to Integer Array         Integer[] integerArray = integerList.toArray(new Integer[integerList.size()]);          // Iterate over the Integer Array         tv.setText(tv.getText() + "\nInteger array (converted) : ");         for(int i=0;i<integerArray.length;i++){             tv.setText(tv.getText() + "" + integerArray[i] + ", ");         }          // Initialize a Boolean ArrayList         List<Boolean> booleanList = new ArrayList<>();         // Add some Boolean value to it         booleanList.add(true);         booleanList.add(false);         booleanList.add(Boolean.FALSE);         booleanList.add(Boolean.TRUE);          // Iterate over the Boolean ArrayList         tv.setText(tv.getText() + "\n\nBoolean list : ");         for(int i=0;i<booleanList.size();i++){             tv.setText(tv.getText() + "" + booleanList.get(i) + ", ");         }          // Convert the Boolean list to Boolean Array         Boolean[] booleanArray = booleanList.toArray(new Boolean[booleanList.size()]);          // Loop through the converted Boolean Array         tv.setText(tv.getText() + "\nBoolean array (converted) : ");         for(int i=0;i<booleanArray.length;i++){             tv.setText(tv.getText() + "" + booleanArray[i] + ", ");         }     } }
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