Module 4 -Java string method

JAVA String method:

The java.lang.The String class provides many useful methods to perform operations on a sequence of char values.

String-First letter is uppercase, so string is a class.

Method 1:
char charAt(int index)
It returns a char value for the particular index.
Character at given index
Return type: Char

Output comment:
char in =s.charAt(0);
System.out.println(in);

Method 2:
int length()
The String class length() method returns the length of the specified String.
Number of characters in string
Return type: int

Output Comment:
int l=s.length ();
System.out.println(l);

Method 3:
trim()
Removes leading and trailing spaces
Return type: String

Output:
String v= s.trim();
System.out.println(v);

Method 4:
startsWith(prefix)
Checks if the string starts

Return type: boolean

Output:
boolean bo= s.startsWith("Sa");
System.out.println(bo);//True

Method 5:
endsWith(suffix)
Checks if the string ends with a specified sequence.

Return type: boolean

Output:
boolean lo= s.endsWith("Sa");
System.out.println(lo);//false

Method 6:
toCharArray()
Converts to a char array

Return type: char[]

Output:

Method 7:
isEmpty()
Checks if empty

Return type: boolean

Output:

isBlank()
The method is a predefined method in the String class that checks whether a string is empty or contains only whitespace characters.

Method 8:
toUpperCase()
The Java String toUpperCase () method converts it into the String's lowercase letters
Converts to upper case
Return type: String

Output:
String vv =s.toUpperCase();
System. out.println(vv);//SACHIN HELLO

Method 9:
toLowerCase()
The Java String toLowerCase () method converts it into the String's lowercase letters
Converts to lower case

**Return type: **String

Output:
String sv =s.toLowerCase();
System.out.println(sv);//sachin hello

Method 10:
subString method:
Returns substring from index to end
Return type: String (i)

Output:
String sub =s.substring(0)
System.out.println(sub);

Method 11:
replace() method:
Replace character or substring

Output:
String re= s.replace('S', 'H');
System.out.println(re);
Return type: String('i','j');

Method 12:
replaceAll();
Replace all words.

Output:
String str =s.replaceAll("Sachin", "Hello");
System.out.println(str);
Return type: String("String","String");

Method 13:
split();
Splits a string based on a regex.

Output:

Return type:

Method 14:
join();
The method combines multiple strings using a delimiter.

Output:
String result = si.join(" ", "I","Love", "Java");
System.out.println(result);
Return type: String();

Method 15:
contains()
Checks if a sequence of characters is present in the string.