# StringBuffer

Introduction to Java StringBuffer class.

# String Buffer class

Key Points :-

  • used to created mutable (modifiable) string.
  • **Mutable** :- Which can be changed.
  • is thread-safe i.e. multiple threads cannot access it simultaneously.
  • Methods :-

  • public synchronized StringBuffer append(String s)
  • public synchronized StringBuffer insert(int offset, String s)
  • public synchronized StringBuffer replace(int startIndex, int endIndex, String str)
  • public synchronized StringBuffer delete(int startIndex, int endIndex)
  • public synchronized StringBuffer reverse()
  • public int capacity()
  • public void ensureCapacity(int minimumCapacity)
  • public char charAt(int index)
  • public int length()
  • public String substring(int beginIndex)
  • public String substring(int beginIndex, int endIndex)
  • Example Showing diffrence between String and String Buffer implementation :-

    class Test {
     public static void main(String args[])
     {
      String str = "study";
      str.concat("tonight");
      System.out.println(str);      // Output: study
    
      StringBuffer strB = new StringBuffer("study");
      strB.append("tonight");
      System.out.println(strB);    // Output: studytonight
     }
    }