Array tools and common exceptions

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1. Use of Arrays tool class
Java.util.Arrays class is the tool class for manipulating arrays, including various methods for manipulating arrays (such as sorting and searching).

Examples of Sort() methods:

2. Common in the use of arrays Exception
1. Array IndexOutOfBoundsException (ArrayIndexOutOfBoundsException)
int[] arr = new int[2];
System.out.println(arr[2]);
System.out.pirntln(arr[-1]);
Access to the array Occurs when a subscript does not exist in the.
2, NullPointerException (NullPointerException)
int[] arr = null;
System.out.println(arr[0]); The
arr reference does not point to the entity, but the element in the entity is to be manipulated.