JAVA

java.lang.arrayindexoutofboundsexception: index 3 out of bounds for length 3

Since in java the first position of an array is 0, if an array has 
length 3 then the last element is in position 2. 

Ex: array = [elem0, elem1, elem2] then the last elem is index 2 
and the array has length 3 

java.lang.ArrayIndexOutOfBoundsException

import java.util.Random;
public class demo{
  public static void main(String[]args){
    Random rand=new Random();
    int array[]=new int[10];
    for(int i=0;i<array.length;i++){
      array[i]=rand.nextInt(100);//random between 0 and 100
    }
    System.out.println(array[array.length]);// error java.lang.ArrayIndexOutOfBoundsException
    // because index start 0 and end array.length
  }

}

java.lang.arrayindexoutofboundsexception: -1

check the code if it is accesing the element at negative index

ArrayIndexOutOfBoundsException

class AccessArrayOutsie
{
    public static void main (String[] args)
    {
        int[] array = new int[3];
        array[0] = 3;
        array[1] = 5;
  	array[2] = 6;
 
        for (int i = 0; i <= array.length; i++)
            System.out.println(array[i]);
    }
}