How to use String indexof () in Java

There are four ways to find string substrings in Java (indexof ())

The IndexOf method returns an integer value that indicates the starting position of the substring in the string object. If no substring is found, 1 is returned.
If the startindex is negative, then startindex is treated as zero. If it is larger than the maximum character position index, it is treated as the largest possible index.

There are four ways to find string substrings in Java, as follows:
1, int indexOf (String str): Returns the index of the first occurrence of the specified substring in this string.
2, int indexOf (String str, int startIndex): Returns the index of the first occurrence of the specified substring in this string, starting at the specified index.
3, int lastIndexOf (string str): Returns the index of the specified substring that appears rightmost in this string.
4, int lastIndexOf (String str, int startIndex): Searches backward at the specified index, returning the index of the specified substring that last occurred in this string.

 Public classTest { Public Static voidMain (string[] args) {String s="xxccxxxxx"; //find out if the specified character is present from the beginning//The results are as followsSystem. out. println (S.indexof ("C"));//2//continues the search from the fourth character position, including the current positionSystem. out. println (S.indexof ("C",3));//3//The system returns 1 if the character is not in the specified string.System. out. println (S.indexof ("y"));//-1System. out. println (S.lastindexof ("x"));//6    }}

How to use String indexof () in Java