-
java.lang.StringBuffer class comes with many helper methods to manipulate string. One of the methods is overloaded indexOf() method used to search for the first occurrence of a string in the buffer.
- public int indexOf(String searchString): Returns an int value of the index number of first occurrence of searchString in the buffer. Returns -1 if the searchString is not found.
- public synchronized int indexOf(String searchString, int searchIndex): Returns an int value of the index number of first occurrence of searchString in the buffer where search starts from searchIndex. Returns -1 if the searchString is not found.
Let us see what Java API says about indexOf() StringBuffer:
Following indexOf() StringBuffer example illustrates the usage of two overloaded method in all possible ways.
public class Demo
{
public static void main(String args[])
{ // hello comes in 3 places
StringBuffer sb1 = new StringBuffer("123hello456hello789hello");
// to find 1st occurrence of hello
int x = sb1.indexOf("hello");
System.out.println("First Occurrence of hello: " + x);
// to find first occurrence of hello starting from 9th index number
x = sb1.indexOf("hello", 9);
System.out.println("Occurrence of hello from index 9: " + x);
x = sb1.indexOf("world"); // world does not exist
System.out.println("Occurrence of world which does not exist: " + x);
}
}

Output screenshot on indexOf() StringBuffer example
Pass your comments and suggestions on this tutorial "indexOf() StringBuffer Example".