Regular Expressions, or Regex (for short), are APIs for defining string patterns that can be used to find, manipulate, and manipulate strings in Java. Email and password validation are some of the string ranges that regex often use to set limits. Regular expressions are provided under Java. util.regex package. It consists of 3 classes and 1 interface. So, in summary, we can conclude that Java regular expressions are used to find, match, and retrieve data from strings.
Approach: We can convert String to String Array using the split method of the String class and Regular Expression.
Methods:
Method 1: Using split() method only
Example:
// Java program to demonstrate how to convert String to // String Array using Regular Expression in Java // Importing all classes from // java.util package import java.util.*; // Importing Matcher class that searches through a text for // multiple occurences of a regular expression import java.util.regex.Matcher; // Importing Pattern class import java.util.regex.Pattern; // Importing Pattern class to compile regex // Class class GFG { // Main driver method public static void main(String[] args) { // Random string input String gfg = "Welcome, to, GFG"; // Splitting of string into characters and // storing it in an array string // separated by comma in between characters String[] str = gfg.split(","); // Traversing the above array // using for each loop for (String s : str) { // Print the characters of the array // formed from input string System.out.println(s); } } }
Output
Welcome to GFG
Method 2: Using ‘?!^’ regular expression along with split() method
Approach:
With the split method, we will use the ?!^ Regular Expression that split the string. And extract data of character sequence.
Example:
// Java program to demonstrate how to convert String to // String Array using Regular Expression in Java // Importing all classes from // java.util package import java.util.*; // Importing Matcher and Pattern classes from // java.util.regex package because // Matcher Class searches through a text for // multiple occurences of a regular expression import java.util.regex.Matcher; // Pattern Class to compile regex import java.util.regex.Pattern; // Class class GFG { // Main driver method public static void main(String[] args) { // Random input string String gfg = "Welcome, to, GFG"; // Split the above input string // using split() method and // store the input string elements as an array String[] str = gfg.split("(?!^)"); // Print all the elements of an array System.out.println(Arrays.toString(str)); } }
Output
[W, e, l, c, o, m, e, ,, , t, o, ,, , G, F, G]