String Class Java

#java

Strings

Strings are variables used in Java for storing text. They are immutable which means they cannot be changed.

There are two different ways to create strings:

String literal
String s1= "John";

Using the new keyword
String s2 = new String("Tim");

indexOf()- returns the position of the first occurrence of a specified string as an integer.
System.out.println(s1.indexOf("o"));
1

length()-returns the length of the string as an integer.
System.out.println(s2.length());
3

substring()-returns characters from a string from a specified beginning to a specified end point.
System.out.println(s1.substring(1,3));
oh

toLowerCase()/toUpperCase()- converts the string to uppercase or lowercase.
System.out.println(s1.toUpperCase());
JOHN