loginaction.java

struts+hibernate+spring的一个很好的例子

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.ActionMessages;
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.dao.UserDAO;
import com.demo.struts.forms.LoginForm;
import com.demo.struts.util.Constants;

public class LoginAction extends DispatchAction {

	protected UserDAO userDAO;

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

	public UserDAO getUserDAO() {
		return userDAO;
	}

	public void setUserDAO(UserDAO userDAO) {
		this.userDAO = userDAO;
	}

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

		ActionMessages messages = new ActionMessages();
		ActionForward forward = new ActionForward();
		LoginForm loginForm = (LoginForm) form;

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

			// 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
			boolean isValid = valid(request, loginForm);
			if (isValid) {
				session.setAttribute(Constants.USERNAME_KEY, username);

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

		} catch (Exception e) {
			messages.add(ActionMessages.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 (!messages.isEmpty()) {
			saveErrors(request, messages);
			request.setAttribute("loginFormBean", loginForm);
			forward = mapping.findForward(Constants.FAILURE_KEY);
		} else {
			forward = mapping.findForward(Constants.SUCCESS_KEY);
		}

		// Finish with
		return (forward);
	}

	private boolean valid(HttpServletRequest request, LoginForm loginForm) {
		if (getUserDAO().isValid(loginForm.getUsername(),
				loginForm.getPassword())) {
			return true;
		} else {
			return false;
		}
	}
}