StringBuilder方法插入，删除和deleteCharAt。

public class Main 

{

   public static void main(String[] args)
   /** 
   来 自 
   N o w  J a v a  . c o m
   **/

   {

      Object objectRef = "hello";  

      String string = "goodbye";  

      char[] charArray = {'a', 'b', 'c', 'd', 'e', 'f'};

      boolean booleanValue = true;

      char characterValue = 'K';

      int integerValue = 7;

      long longValue = 10000000;

      float floatValue = 2.5f; // f suffix indicates that 2.5 is a float

      double doubleValue = 33.333;


      StringBuilder buffer = new StringBuilder();


      buffer.insert(0, objectRef)

            .insert(0, "  ") // each of these contains new line

            .insert(0, string)

            .insert(0, "  ")// 来 自 n o w j a v a . c o m - 时代Java

            .insert(0, charArray)

            .insert(0, "  ")

            .insert(0, charArray, 3, 3)

            .insert(0, "  ")

            .insert(0, booleanValue)

            .insert(0, "  ")

            .insert(0, characterValue)

            .insert(0, "  ")

            .insert(0, integerValue)

            .insert(0, "  ")

            .insert(0, longValue)

            .insert(0, "  ")

            .insert(0, floatValue)

            .insert(0, "  ")

            .insert(0, doubleValue);