jspの下にある木の展示



<%@ page language="java" contentType="text/html; charset=gbk"
    pageEncoding="gbk"%>
<%@page import="java.sql.*" %>
<%!
String str = "";//       html  
private void tree(Connection conn, int id, int level) {
    Statement stmt = null;
    ResultSet rs = null;
    String preStr = "";
    for(int i = 0; i < level; i++) {//    
        preStr += "----";
    }
    try{
        stmt = conn.createStatement();
        rs = stmt.executeQuery("select * from article where pid =" + id);

        while(rs.next()) {//           
            str += "<tr><td>" + rs.getInt("id") + "</td><td>" + preStr + 
                   rs.getString("title") + "</td>" + 
                   "</tr>";
            if(rs.getInt("isleaf") != 0) {//       
                tree(conn, rs.getInt("id"), level+1);
            }
        }
    } catch(SQLException e) {
        e.printStackTrace();
    } finally {
        try{
            if(null != rs) {
                rs.close();
                rs = null;
            }
            if(null != stmt) {
                stmt.close();
                stmt = null;
            }
        } catch(SQLException e) {
            e.printStackTrace();
        }
    }
}
%>
<%
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/bbs?user=root&password=root");
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("select * from article where pid = 0");

while(rs.next()) {//       
    str += "<tr><td>" + rs.getInt("id") + "</td><td>" + 
           rs.getString("title") + "</td>" +
           "</tr>";
    if(rs.getInt("isleaf") != 0) {//          
        tree(conn, rs.getInt("id"), 1);
    }
}
rs.close();
stmt.close();
conn.close();
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=gbk">
        <title>ShowArticleTree</title>
    </head>
    <body>
        <table border="1">
        	<!--       -->
            <%=str %>
        </table>
    </body>
</html>