Can't access a public variable [duplicate]

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• What does a “Cannot find symbol” compilation error mean? 2 answers

I'm trying to use a variable through a getter, but I cant't seem to access the variable. Here is the code, its a random number generator which is supposed to decide a random color. Any help is greatly appreciated.

import java.util.Random;

public class RNG {

  public void startRNG(){

    int START = 1;
    int END = 10;
    Random random = new Random();
    for (int idx = 1; idx <= 10; ++idx){
      showRandomInteger(START, END, random);
    }
  }

  public void showRandomInteger(int aStart, int aEnd, Random aRandom) {
    long range = (long)aEnd - (long)aStart + 1;
    long fraction = (long)(range * aRandom.nextDouble());
    int randomNumber =  (int)(fraction + aStart); // The variable I'm trying to access

  }

  public int getRandomNumber() {
      return randomNumber; // Can't access randomNumber
  }

  public void colorChooser() {
      switch (getRandomNumber()) {
      case 1:
          break;
      case 2:
          break;
      case 3:
          break;
      case 4:
          break;
      case 5:
          break;
      case 6:
          break;
      case 7:
          break;
      case 8:
          break;
      case 9:
          break;
      case 10:
          break;
      }
  }

}