Predefined Methods in String смотреть онлайн

Java Strings Predefined Methods
===============
String:- String is Group of characters
number :- single digit ,combination of digits
String in java is a predefined class which provides readymade methods to perform operations on group of characters
1. length() :- This method is used to count the no of characters that are available in the given string
String x="kannababu";
System.out.println(x.length());
Ex:-
class StrDemo
{
public static void main(String[] args)
{
String x="kannababu";
System.out.println(x.length());
}
}
2.String toLowerCase() :- This method is used to convert uppercase string into lowercase string
class StrDemo
{
public static void main(String[] args)
{
String x="KANNABABU";
System.out.println(x.toLowerCase());
}
}
3. String toUpperCase():- This method is used to convert lower string into uppercase string
class StrDemo
{
public static void main(String[] args)
{
String x="kannababu";
System.out.println(x.toUpperCase());
}
}
4. String concat(String str):-
class StrDemo
{
public static void main(String[] args)
{
String x="kannababu";
System.out.println(x.concat("is a trainer"));
}
}
5. String substring(int beginindex):- This method is used to return the substring from the given string
class StrDemo
{
public static void main(String[] args)
{
String x="kannababutrainer";
System.out.println(x.substring(5));
}
}
String substring(int beginindex,int endindex):- This method is used to return the substring from the given string
class StrDemo
{
public static void main(String[] args)
{
String x="kannababutrainer";
System.out.println(x.substring(5,9));
}
}
6. charAt():- This method returns the character at a specific position
String str="welcome";
char ch=str.charAt(0);
System.out.println(ch);
7. compareTo():-This method is used to compare 2 strings
class StrDemo
{
public static void main(String[] args)
{
String str1="welcome";
String str2="welcome";
System.out.println(str1.compareTo(str2));
}
}
8. replace():- replace a specific in the given string
class StrDemo
{
public static void main(String[] args)
{
String s="there,is,a,cat";
System.out.println(s.replace(',',' '));
}
}
Q) String s="sat56h72a";
wap to find the sum of the digits in the given string?
a-z 65-90
A-Z 97-122
0-9 48-57