StringBuffer class Demo.

StringBufferDemo.java

/*
 * StringBufferDemo.java
 *
 * StringBuffer class Demo.
 *
 * A thread-safe, mutable sequence of characters.
 * A string buffer is like a String, but can be modified.
 * At any point in time it contains some particular sequence of characters,
 * but the length and content of the sequence can be changed through certain method calls.
 *
 * Usage:
 *   javac StringBufferDemo.java && java StringBufferDemo
 */

class StringBufferDemo {

  public static void main(String args[]) {

    StringBuffer sb = new StringBuffer("hello");
    sb.append("java");
    System.out.println(sb);
  }

}