JSP与ajax无刷新判断日志重复并保存实例

<%@ page language="java" import="java.util.*,jform.Allclass" contentType="text/html;charset=gb2312"%>  
  
  
  
  
  
  
  
  

/* 
     * 日志查重 
     */ 
    int isSave=1;  
    public int logRepeat(String log_title)  
    {  
        ResultSet rs=null;  
        Statement stm=null;  
        StringBuffer sb = new StringBuffer();  
        //sb.append("select * from log_add where log_title = ").append("'");  
        //sb.append("这是一个测试的日志3").append("'");  
        String sq="select * from log_add where log_title = ?";   
        //String sql="select * from log_add where log_title=";   
        try{  
            stm= dd.con.createStatement();  
            pstm=dd.con.prepareStatement(sq);  
            pstm.setString(1, log_title);  
            rs=pstm.executeQuery();  
            //rs=stm.executeQuery(sb.toString());  
            //rs=stm.executeQuery(sq);  
            //rs.next();  
            if(rs.next())isSave=-1;  
            //System.out.println(sb.toString());  
            //System.out.println(log_title);  
            //System.out.println(dd.con);  
            }  
            catch(Exception e){  
                System.out.print(e);  
            }  
            return isSave;  
    }