JAVA （StringBuffer/StringBuilder）常用API

 public class Copy3 {

     public static void main(String[] args) {
         //构造实例化
         StringBuffer strbu = new StringBuffer("hello world\t");
         char[] a = {'l','o','y','o','u'};
         //调用方法

         System.out.println(1+"\t"+strbu.append(true));            //append(boolean b);
         System.out.println(2+"\t"+strbu.append('a'));            //append(char b);
         System.out.println(3+"\t"+strbu.append(a));                //append(char[] b);
         System.out.println(4+"\t"+strbu.capacity());            //capacity();
         System.out.println(5+"\t"+strbu.charAt(10));            //charAt(int index);
         System.out.println(6+"\t"+strbu.delete(3, 9));            //delete(int start, int end);
         System.out.println(7+"\t"+strbu.insert(5, false));        //insert(int offset, boolean b);
         System.out.println(8+"\t"+strbu.substring(7));            //substring(int start)
         System.out.println(9+"\t"+strbu.reverse() );            //reverse() 

     }

 }

运行结果