Construct the same String three different ways

StringBufferDemo.java

/**
 * StringBufferDemo: construct the same String three different ways.
 */
public class StringBufferDemo {
 public static void main(String[] argv) {
 String s1 = "Hello" + ", " + "World";
 System.out.println(s1);
 // Build a StringBuffer, and append some things to it.
 StringBuffer sb2 = new StringBuffer( );
 sb2.append("Hello");
 sb2.append(',');
 sb2.append(' ');
 sb2.append("World");
 // Get the StringBuffer's value as a String, and print it.
 String s2 = sb2.toString( );
 System.out.println(s2);
 // Now do the above all over again, but in a more
 // concise (and typical "real-world" Java) fashion.
 StringBuffer sb3 = new StringBuffer( ).append("Hello").
 append(',').append(' ').append("World");
 System.out.println(sb3.toString( ));
 // Exercise for the reader: do it all again but without
 // creating ANY temporary variables.
 }
}