Servlet：
public class StaticsServlet extends HttpServlet{
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
PreparedStatement pstmt = null;
Connection conn = DB.getConnection(); //注意这里要获取到数据库的连接操作
request.setCharacterEncoding("UTF-8");
response.setContentType("text/html;charset=UTF-8");
ResultSet rs = null;
String sql = "select count(*) FROM recard ";//执行SQL进行统计
try {
pstmt = conn.prepareStatement(sql);
} catch (SQLException e2) {
// TODO Auto-generated catch block
e2.printStackTrace(); }
try {
rs = pstmt.executeQuery();
} catch (SQLException e1){
// TODO Auto-generated catch block
e1.printStackTrace(); }
int num = 0;
try {
while (rs.next()) { //防止在结果集之前运行出现异常
num = rs.getInt(1); //取出结果集的第一列的值情况
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
request.setAttribute("num", num);
request.getRequestDispatcher("/Statics.jsp").forward(request, response);
System.out.println("++++++++++++" + num);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doGet(request, response);
}Statics.jsp:
<body>
<% Integer num=(Integer)request.getAttribute("num");%>
<table>
<th>已借数量</th>
</table>
<td><%=num %></td>主要是连接数据库之后 对数据库进行统计操作
得到的数据会存放在结果集中 然后把结果集里面的数据拿出来
传给jsp页面