字符串方法concat。

public class Main 

{

   public static void main(String[] args)

   {
   /* from 
   时代Java公众号 - nowjava.com*/

      String s1 = "Happy ";

      String s2 = "Birthday";


      System.out.printf("s1 = %s\ns2 = %s\n\n",s1, s2);

      System.out.printf(

         "Result of s1.concat(s2) = %s\n", s1.concat(s2));

      System.out.printf("s1 after concatenation = %s\n", s1);

   } 

}