session取值为空
登录成功 ，登录数据已经存入session ，经验证取证正常。但是向数据库添加数据的过程中 session取值竟然为空。费解！！
1.登录servlet 登录成功并转向，session成功写入。
- Java code
package ser;import impl.AccountImpl;import it.shopping.dao.IAccount;import it.shopping.pojo.Account;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class AccountSer extends HttpServlet{ private IAccount accountImpl = new AccountImpl(); private static final long serialVersionUID = -3708568559174453120L; public AccountSer() { super(); } public void destroy() { super.destroy(); // Just puts "destroy" string in log // Put your code here } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String status = request.getParameter("status"); if(status.equals("login")) { Account account = new Account(); account.setAlogin(request.getParameter("alogin")); account.setApass(request.getParameter("apass")); account =accountImpl.queryAccount(account); if(account == null) { request.setAttribute("error", "登录失败"); request.getRequestDispatcher("/alogin.jsp").forward(request, response); // response.sendRedirect("alogin.jsp"); } { request.getSession().setAttribute("account", account); // response.sendRedirect("/t31/admin/index.jsp"); // 重定向和请求装啊session值都不会失效！ request.getRequestDispatcher("/admin/index.jsp").forward(request, response); } } } public void init() throws ServletException { // Put your code here }}2.跳转至index.jsp成功，然后添加数据成功，跳转至servlet 即CategorySer.java成功
但是在category.setAccount((Account) req.getSession().getAttribute("account"));
session 取值竟然为空！！求解释！！
- Java code
package ser;import impl.CategoryImpl;import it.shopping.dao.ICategory;import it.shopping.pojo.Account;import it.shopping.pojo.Category;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class CategorySer extends HttpServlet{ private ICategory categoryImpl = new CategoryImpl(); public void destroy() { super.destroy(); }@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException{ this.doPost(req,resp);}@Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { String status = req.getParameter("status"); if(status.equals("savaCategory")); { Category category = new Category(); category.setCtype(req.getParameter("ctype")); category.setChot(Boolean.parseBoolean(req.getParameter("chot"))); category.setAccount((Account) req.getSession().getAttribute("account")); System.out.println(category.getAccount()); categoryImpl.queryCategory(category); resp.sendRedirect("/t31/admin/main.jsp"); } } public void init() throws ServletException { }}
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ＰＳ：account
- Java code
package it.shopping.pojo;public class Account{ private int aid; private String alogin; private String apass; public int getAid() { return aid; } public void setAid(int aid) { this.aid = aid; } public String getAlogin() { return alogin; } public void setAlogin(String alogin) { this.alogin = alogin; } public String getApass() { return apass; } public void setApass(String apass) { this.apass = apass; } }Category.java
- Java code
package it.shopping.pojo;public class Category{ private int cid; private String ctype; private Boolean chot; private Account account; public int getCid() { return cid; } public void setCid(int cid) { this.cid = cid; } public String getCtype() { return ctype; } public void setCtype(String ctype) { this.ctype = ctype; } public Boolean getChot() { return chot; } public void setChot(Boolean chot) { this.chot = chot; } public Account getAccount() { return account; } public void setAccount(Account account) { this.account = account; } }CategoryImp.java
- Java code
package impl;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import utils.JdbcUtils;import it.shopping.dao.ICategory;import it.shopping.pojo.Category;public class CategoryImpl implements ICategory{ @Overridepublic Category queryCategory(Category category) { Connection conn = null; PreparedStatement pre = null; String sql =" INSERT INTO category {?,?,?}"; ResultSet rs = null; try { System.out.println("hello3.0"); conn = JdbcUtils.getConnection(); pre = conn.prepareStatement(sql); System.out.println("hello4.0"); System.out.println(category.getAccount().getAid()); pre.setInt(1,category.getAccount().getAid()); pre.setString(2, category.getCtype()); pre.setBoolean(3,category.getChot()); System.out.println("hello6.0"); pre.executeQuery(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally { JdbcUtils.free(rs, pre, conn); } return category; }}[解决办法]