viewpageaction.java

一个汽车售后服务站的典型的进销管理系统,B/S模式的

/*
 * Generated by MyEclipse Struts
 * Template path: templates/java/JavaClass.vtl
 */
package com.xfaccp.struts.action.others;

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

import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

import com.xfaccp.base.PageInfo;
import com.xfaccp.base.ViewPageForm;


/** 
 * MyEclipse Struts
 * Creation date: 09-02-2007
 * 
 * XDoclet definition:
 * @struts.action
 */
public class ViewPageAction extends Action {
	/*
	 * Generated Methods
	 */

	/** 
	 * Method execute
	 * @param mapping
	 * @param form
	 * @param request
	 * @param response
	 * @return ActionForward
	 */
	public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response) {
		
		
        String targetPage = ((ViewPageForm) form).getTargetPage();

        HttpSession session = request.getSession();

        PageInfo pager = (PageInfo) session.getAttribute("pager");
        
        /*
         * 这种方法让用户输入查看的页面是不太稳当的
         * 由于输入错误或转换等错误等都会对应用程序造出混乱
         * 解决方案：可以将所有的页数值放入下拉列框中让用户选择就好了！！
         */
        try {
        	// 判断是否超出页面范围
            if ((Integer.parseInt(targetPage) > pager.getTotalPages()) ||
                    (Integer.parseInt(targetPage) < 1))
            {
            	//若超出则仍定位到当前页面
                targetPage = String.valueOf(pager.getCurrentPage());

            }
            // 如果输入的不是数字，也就是抛出NumberFormatException异常，
        } catch (NumberFormatException e) {
            e.printStackTrace();
            targetPage = String.valueOf(pager.getCurrentPage());

        }
        request.removeAttribute(mapping.getAttribute());
        return (new ActionForward("/displayAllBooks.do?viewPage=" + targetPage));

	}
}