java替换字符串占位符 java字符串位置替换

/**
  * @创建日期 2013-07-15
  * @创建时间 14:25:59
  * @版本号 V 1.0
  */
public  class  CosTest {
     public  static  void  main(String[] args) {
         String sql =  "select * from teacher  where id = ? and name = ?" ;
         System.out.println(replaceString(sql, "101" , 2 ));
     }
 
     public  static  String replaceString(String str, String rstr,  int  a) {
         String searchStr =  "?" ;
         int  index = str.indexOf(searchStr);
         int  count =  1 ;
         while  (count != a) {
             index = str.indexOf(searchStr, index +  1 );
             count++;
         }
 
         return  str.substring( 0 , index) + rstr + str.substring(index +  1 );
     }
}