loginaction.java

java web开发者突击程序 Struts+Hibernate实例源码

package com.demo.struts.actions;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.log4j.Logger;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessage;
import org.apache.struts.actions.DispatchAction;

import com.demo.hibernate.beans.User;
import com.demo.hibernate.dao.UserDAO;
import com.demo.struts.forms.LoginForm;
import com.demo.struts.util.Constants;

public class LoginAction extends DispatchAction {

	Logger log = Logger.getLogger(this.getClass());

	public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {

		ActionErrors errors = new ActionErrors();
		ActionForward forward = new ActionForward();
		LoginForm loginForm = (LoginForm) form;

		try {
			// get parameters
			String username = loginForm.getUsername();
			String password = loginForm.getPassword();

			// invalidate the original session if exists
			HttpSession session = request.getSession(false);
			if (session != null) {
				session.invalidate();
			}

			// create a new session for the user
			session = request.getSession(true);

			// login			
			if (valid(loginForm)) {
				session.setAttribute(Constants.USERNAME_KEY, username);

				log.info("User " + username + " login.");
			} else {
				errors.add(ActionErrors.GLOBAL_MESSAGE, new ActionMessage(
						"login.message.failed"));
			}

		} catch (Exception e) {
			errors.add(ActionErrors.GLOBAL_MESSAGE, new ActionMessage(
					"login.message.failed"));

		}

		// If a message is required, save the specified key(s)
		// into the request for use by the <struts:errors> tag.

		if (!errors.isEmpty()) {
			saveErrors(request, errors);
			request.setAttribute("loginFormBean", loginForm);
			forward = mapping.findForward(Constants.FAILURE_KEY);
		} else {
			forward = mapping.findForward(Constants.SUCCESS_KEY);
		}

		// Finish with
		return (forward);
	}
	
	private boolean valid(LoginForm loginForm) {
		UserDAO userDAO = new UserDAO();
		User user = userDAO.valid(loginForm.getUsername(), loginForm.getPassword());
		if (user != null) {
			return true; 
		} else {
			return false;
		}
	}
}