Java example to convert string into string array using String.split()
method and using java.util.regex.Pattern
class.
Quick Reference:
//1. String to String[] String blogName = "how to do in java"; String[] words = null; // Method 1 :: using String.split() method words = blogName.split(" "); //[how, to, do, in, java] // Method 2 :: using Pattern.split() method Pattern pattern = Pattern.compile(" "); words = pattern.split(blogName); //[how, to, do, in, java] //2. String[] to String String newName = String.join(" ", words); //"how to do in java"
1) Convert String to String[]
1.1) String.split()
Use split()
method to split string into tokens by passing a delimiter (or regex) as method argument.
import java.util.Arrays; public class Main { public static void main(String[] args) { String names = "alex,brian,charles,david"; String[] namesArray = null; //Split string with comma namesArray = names.split(","); //Verify array content System.out.println(Arrays.toString(namesArray)); } } Output: [alex, brian, charles, david]
1.2) Pattern.split()
In Java, Pattern
is the compiled representation of a regular expression. Use Pattern.split()
method to convert string to string array, and using pattern as delimiter.
import java.util.Arrays; public class Main { public static void main(String[] args) { String names = "alex,brian,charles,david"; String[] namesArray = null; //Split string with comma Pattern pattern = Pattern.compile(","); namesArray = pattern.split( names ); //Verify array content System.out.println(Arrays.toString(namesArray)); } } Output: [alex, brian, charles, david]
2) String[] to String
Use String.join()
method to create string from String array. You need to pass two method arguments i.e.
- delimiter – the delimiter that separates each element
- array elements – the elements to join together
It will then return a new string that is composed of the ‘array elements’ separated by the ‘delimiter’.
public class Main { public static void main(String[] args) { String[] tokens = {"How","To","Do","In","Java"}; String blogName1 = String.join("", tokens); //without space String blogName2 = String.join(" ", tokens); //with one space String blogName3 = String.join("-", tokens); //with hyphen //Verify string System.out.println(blogName1); System.out.println(blogName2); System.out.println(blogName3); } } Output: HowToDoInJava How To Do In Java How-To-Do-In-Java
Drop me your questions in comments section.
Happy Learning !!
String.split() Java Doc
String.join() Java Doc
Pattern Java Doc
Arrays.toString() Java Doc
Hi Lokesh, can you please help me with this problem.
1. I want to store the float type array into the derby database and
2. also retrieve the data in the same form.