stringbuffer

 StringBuffer useinfo=new StringBuffer();
 Connection conn=lianjie.getConn();
 Statement stmt=conn.createStatement();
 ResultSet rs=stmt.executeQuery("select * from messagebook");
 
 try{
 while(rs.next()){
  useinfo.append("\n");
  useinfo.append(""+rs.getString("uid")+"");
  useinfo.append(""+rs.getString("name")+"");
  useinfo.append(""+rs.getString("ip")+"");
  useinfo.append(""+rs.getString("email")+"");
  useinfo.append(""+rs.getString("exactpost")+"");
  useinfo.append(""+rs.getString("content")+"");
  useinfo.append("");
 }
 }catch(Exception ex){
  System.out.println(ex);
 }