charAt(int index): get the char at specified index

The value of a single character can be obtained from a StringBuffer via the charAt( ) method.

char charAt(int index)

Returns the char value in this sequence at the specified index.

public class Main {
  public static void main(String[] argv) {
    StringBuffer sb = new StringBuffer();
    sb.append("java2s.com");
    
    char ch =  sb.charAt(0);
    
    System.out.println(ch);

  }
}

The output:

j

1. Create StringBuffer object
2. append
3. StringBuffer capacity()
4. charAt(int index): get the char at specified index
5. delete(int start, int end) and deleteCharAt(int index)
6. ensureCapacity( )
7. getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)
8. indexOf(String str)
9. lastIndexOf(String str)
10. StringBuffer length()
11. Insert(): add data in the middle of a StringBuffer
12. replace():replace a StringBuffer
13. StringBuffer reverse()
14. setCharAt(int index, char ch)
15. setLength
16. substring
17. toString():Convert StringBuffer to String