StringBuffer

Introduction#

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
 }
}