课程 6：编辑操作映射

操作映射表示一项在运行的操作。当它正在运行时，它将确定应用程序的流。

操作映射是一个配置文件条目，通常包含对操作类的引用。此条目可以包含对某操作可使用的表单 bean 的引用，此外，还可以定义仅对此操作可视的本地转发和异常。为 JavaServer Pages（JSP）页编写代码时，可以引用操作映射以触发某项操作。

操作类中包含在提交表单时就会调用的 execute 方法。在此方法中，可以提供逻辑以确定计算结果是“成功”（由指向输出 JSP 页的转发来定义）还是“失败”（由指向输入 JSP 页的转发来定义）。

要编辑操作映射：

在“项目资源管理器”中，浏览至 DayOfWeek\Java Resources: src\dayofweek.actions 文件夹。
双击 ComputeDayAction.java 文件以将它打开。
在该文件中，选择所有文本并按 Delete 键以删除这些文本。

复制以下代码并将它粘贴到该文件中：

package dayofweek.actions;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionError;
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 com.ibm.dayofweek.DateData;


/**
  * @version 	1.0
  * @author
 */

public class ComputeDayAction extends Action {

  /**
   * Constructor
   */
  public ComputeDayAction() {

    super();

  }

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

    		ActionErrors errors = new ActionErrors();
    		ActionForward forward = new ActionForward();
    // return value
    		DateData dateData = (DateData) form;
    		int year;
    		int month;
    		int day;
    		int dayOfWeek;
    		int valcen;
    		int valleap;
    		int valyear;
    		int valmon;
    		int valday;
    		int[] centuries = new int[4];
    		int[] months = new int[13];
    		String[] daysOfWeek = new String[7];
    		centuries[0] = 2;
    		centuries[1] = 0;
    		centuries[2] = 5;
    		centuries[3] = 3;
    		months[1] = 5;
    		months[2] = 1;
    		months[3] = 0;
    		months[4] = 3;
    		months[5] = 5;
    		months[6] = 1;
    		months[7] = 3;
    		months[8] = 6;
    		months[9] = 2;
    		months[10] = 4;
    		months[11] = 0;
    		months[12] = 2;
    		daysOfWeek[0] = "Sunday";
    		daysOfWeek[1] = "Monday";
    		daysOfWeek[2] = "Tuesday";
    		daysOfWeek[3] = "Wednesday";
    		daysOfWeek[4] = "Thursday";
    		daysOfWeek[5] = "Friday";
    		daysOfWeek[6] = "Saturday";

       try {
      			day = dateData.getDay();
      			month = dateData.getMonth();
      			year = dateData.getYear();
      			if (month < 3) {
        				year--; // Subtract 1 from year
      }
      			valcen = centuries[year / 100 % 4];
      			valleap = year % 100 / 4;
      			valyear = year % 100 % 7;
      			valmon = months[month];
      			valday = day % 7;
      			dayOfWeek = valcen + valleap + valyear + valmon + valday;
      			dayOfWeek = dayOfWeek % 7;
      			dateData.setDayOfWeek(daysOfWeek[dayOfWeek]);
      			request.setAttribute("dateData", dateData);

         } catch (Exception e) {

      			// Report the error using the appropriate name and ID.
      			errors.add("name", new ActionError("id"));
                  e.printStackTrace();
    }

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

    		if (!errors.isEmpty()) {
      			saveErrors(request, errors);
      			forward = mapping.findForward("failure");
             } else {
      			forward = mapping.findForward("success");
    }

    		// Finish with
    		return (forward);

  }

}

提示：您的项目中的包名可能不是 dayofweek.actions。在这种情况下，应将上述第一个代码行中的 dayofweek.actions 替换为您的包名。

保存并关闭该文件。

课程 6：编辑操作映射

课程要点