baseaction.java

本文论述了一个前台笔记本销售系统的开发过程

package com.set.appframe.web;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.apache.commons.fileupload.FileUpload;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.actions.DispatchAction;

import com.set.appframe.business.SpringBeanFactory;
import com.set.appframe.data.GenericValueObject;
import com.set.appframe.exception.SystemException;
import com.set.utils.AppSetting;
import com.set.utils.DateTimeUtils;
import com.set.utils.StringUtils;

/**
 * BaseAction is the Struts Action class that all application Action classes
 * should extend. It also provides routines to perform application level
 * operations, such as:<br>
 * (1) executes filters process all requests and responses in an Web
 * application;<br>
 * (2) handles errors in application with a standard error page;<br>
 * (3) formats output values to the display
 * 
 * @author Oliver Yip
 * @version 1.0, 11/04/03
 * @since 1.0
 */
public abstract class BaseAction extends DispatchAction {

	// private static ApplicationContext ctx = null;
	/**
	 * application setting for application.
	 * 
	 */
	protected AppSetting as = null;

	/**
	 * constructs a <code>BaseAction</code> object.
	 * 
	 * @param as
	 *            Application setting for the application
	 * 
	 */
	public BaseAction(AppSetting as) {
		this.as = as;
	}

	/**
	 * get a bean specificed in a xml file from spring bean factory
	 * 
	 * @param name
	 *            String
	 * @return Object
	 * @author zhifeng history : modified by zhifeng, change the implementation
	 *         of getBean() 2004-11-11
	 */
	public Object getBean(String name) throws SystemException {
		return SpringBeanFactory.getInstance().getBean(name);
	}

	/**
	 * process an HTTP request from Web user.
	 * <p>
	 * The method also handles validation errors from Action Form, and runs the
	 * pre-process and post-process filters.
	 * 
	 * @param mapping
	 *            Struts Action mapping
	 * @param form
	 *            Struts Action form
	 * @param request
	 *            Web HTTP request
	 * @param response
	 *            Web HTTP response
	 * @return Struts Action forward indicating JSP destination to reach after
	 *         the current HTTP request.
	 * @throws Exception
	 *             exceptions happened in handling request
	 * 
	 */
	public ActionForward execute(ActionMapping mapping, ActionForm form,
			javax.servlet.http.HttpServletRequest request,
			javax.servlet.http.HttpServletResponse response) throws Exception {
		ActionForward af = null;

		// Applying pre-process filters
		preProcessFilters(mapping, form, request, response);

		// Checking multipart
		boolean isMultipart = FileUpload.isMultipartContent(request);
		if (isMultipart) {
			af = uploadFile(mapping, form, request, response);
		} else {
			af = super.execute(mapping, form, request, response);
		}
		// Applying post-process filters
		postProcessFilters(mapping, form, request, response);

		return af;
	}

	protected ActionForward uploadFile(ActionMapping mapping, ActionForm form,
			javax.servlet.http.HttpServletRequest request,
			javax.servlet.http.HttpServletResponse response) throws Exception {
		return null;
	}

	/**
	 * executes pre-process filters before a Web request is processed
	 * 
	 * @param mapping
	 *            Struts Action mapping
	 * @param form
	 *            Struts Action form
	 * @param request
	 *            Web HTTP request
	 * @param response
	 *            Web HTTP response
	 * 
	 */
	protected abstract void preProcessFilters(ActionMapping mapping,
			ActionForm form, javax.servlet.http.HttpServletRequest request,
			javax.servlet.http.HttpServletResponse response);

	/**
	 * executes post-process filters after a Web request is processed
	 * 
	 * @param mapping
	 *            Struts Action mapping
	 * @param form
	 *            Struts Action form
	 * @param request
	 *            Web HTTP request
	 * @param response
	 *            Web HTTP response
	 * 
	 */
	protected abstract void postProcessFilters(ActionMapping mapping,
			ActionForm form, javax.servlet.http.HttpServletRequest request,
			javax.servlet.http.HttpServletResponse response);

	/**
	 * handles errors that happen in the application
	 * 
	 * @param mapping
	 *            Struts Action mapping
	 * @param request
	 *            Web HTTP request
	 * @param errKey
	 *            resource key for the error
	 * @param param
	 *            parameters to replace variables in resource string for the
	 *            error
	 * @param user
	 *            current user that experiences the error
	 * @param backURL
	 *            the URL link to return to after the error page has been
	 *            displayed
	 * @param additionalInfo
	 *            additional information for the error
	 * @param excp
	 *            exception that is associated with the error
	 * @return Struts Action forward indicating JSP destination to reach after
	 *         the current HTTP request.
	 * 
	 */
	protected abstract ActionForward handleError(ActionMapping mapping,
			javax.servlet.http.HttpServletRequest request, String errKey, String user, String backURL,Exception excp);

	/**
	 * handles validation errors that happen in the application
	 * 
	 * @param mapping
	 *            Struts Action mapping
	 * @param request
	 *            Web HTTP request
	 * @param err
	 *            validation errors that come from Action Form
	 * @return Struts Action forward indicating JSP destination to reach after
	 *         the current HTTP request.
	 * 
	 */
	protected ActionForward handleError(ActionMapping mapping,
			javax.servlet.http.HttpServletRequest request) {
		return handleError(mapping, request,"","","",null);
	}

	/**
	 * formats date value to display string according to application setting
	 * 
	 * @param d
	 *            date to format
	 * @return formatted display string for date
	 * 
	 */
	protected String formatDate(Date d) {
		return (d == null ? "" : as.dFormat(d));
	}

	/**
	 * formats date values in a GenericValueObject to display strings according
	 * to application setting.
	 * 
	 * @param gvo
	 *            the GenericValueObject to format
	 * @param fields
	 *            array of key strings for the name-value pairs in the
	 *            GenericValueObject to format
	 * @return the resulting GenericValueObject that has date values formatted
	 * 
	 */
	protected GenericValueObject formatDate(GenericValueObject gvo,
			String[] fields) {
		if (fields != null && gvo != null) {
			for (int i = 0; i < fields.length; i++) {
				Object o = gvo.getItem(fields[i]);
				if (o instanceof Date) {
					gvo.add(fields[i], formatDate((Date) o));
				}
			}
		}
		return gvo;
	}

	/**
	 * format long date field to date format
	 * 
	 * @param gvo
	 *            GenericValueObject
	 * @param fields
	 *            String[]
	 * @return GenericValueObject
	 */
	protected GenericValueObject formatDate2(GenericValueObject gvo,
			String[] fields) {
		if (fields != null && gvo != null) {
			for (int i = 0; i < fields.length; i++) {
				String o = gvo.getItemString(fields[i]);
				if (!"0".equals(o) && !"".equals(o)) {
					gvo.add(fields[i], DateTimeUtils.long2DateString(o));
				}
			}
		}
		return gvo;
	}

	/**
	 * @author hj
	 * @CREATEDDATE: 2005-06-17
	 * @param vgvo
	 *            List
	 * @param fields
	 *            String[]
	 * @return List
	 * @DISCRIPTION: 返回带几点几分的日期
	 */
	protected List formatDate3(List vgvo, String[] fields) {
		if (vgvo == null || fields == null) {
			return null;
		}
		List vRet = new ArrayList();
		Iterator eGVO = vgvo.iterator();
		while (eGVO.hasNext()) {
			GenericValueObject gvo = (GenericValueObject) eGVO.next();
			vRet.add(formatDate3(gvo, fields));
		}
		return vRet;
	}

	protected GenericValueObject formatDate3(GenericValueObject gvo,
			String[] fields) {
		if (fields != null && gvo != null) {
			for (int i = 0; i < fields.length; i++) {
				String o = gvo.getItemString(fields[i]);
				if (!"0".equals(o) && !"".equals(o)) {
					Date date = new Date(Long.parseLong(o));
					gvo.add(fields[i], DateTimeUtils.dateToLangString(date));