1.1 CRUD
CRUD(Create，Retrieve or Read?，Update，Delete)是信息管理系统中经常要执行的操作的简称。接下来我们分别描述这几种操作的执行流程。
1.1.1 查询项目信息
执行项目信息查询列表显示的文件请求处理顺序如下：
1、 ProjectListSearchAction
2、 projectlist.jsp
ProjectListSearchAction代码如下：
package com.ort.strutsdemo.simpledemo.controller;
/**
* <p>Title: Struts Training </p>
* <p>Description: Struts内部培训Demo</p>
* <p>Copyright: Copyright (c) 2004</p>
* <p>Company: </p>
* @author Liuz
* @version 1.0
*/
import org.apache.struts.action.*;
import javax.servlet.http.*;
import com.ort.strutsdemo.simpledemo.business.BusinessDelegate;
import com.boss.module.operation.object.Project;
import com.ort.strutsdemo.simpledemo.Constants;
import com.ort.strutsdemo.simpledemo.controller.exception.ExceptionBean;
import com.boss.module.operation.object.searchresult.help.ResultSetIterator;
import com.ort.strutsdemo.simpledemo.ui.ProjectForm;
import com.boss.module.operation.object.searchgene.ProjectSearchGene;
/**
*
* <p>Title: Struts Training </p>
* <p>Description: 项目查询结果数据的装载</p>
* <p>Copyright: Copyright (c) 2004</p>
* <p>Company: ORT</p>
* @author Liuz
* @version 1.0
*/
public class ProjectListSearchAction
extends Action {
BusinessDelegate businessDelegate = null;
public ActionForward execute(ActionMapping actionMapping,
ActionForm actionForm,
HttpServletRequest request,
HttpServletResponse response) {
try {
DynaActionForm form = (DynaActionForm) actionForm;
//定义分页所需要变量
int page= ((Integer)form.get("page")).intValue();
int pageSize = 5;
int allSize = 0;
int pageCount = 0;
//获取用户输入查询值,并形成查询条件
String projectCode = (String)form.get("projectCode");
String projectCodeSign = (String)form.get("projectCodeSign");
String projectName = (String)form.get("projectName");
String projectNameSign = (String)form.get("projectNameSign");
ProjectSearchGene searchGene = new ProjectSearchGene(); //searchGene为一查询精灵，用以处理查询操作，在此不用过多关注，有机会在另文介绍
searchGene.setProjectCode(projectCode, projectCodeSign);
searchGene.setProjectName(projectName, projectNameSign);
//装载当前页面所需要显示项目列表数据
BusinessDelegate businessDelegate = BusinessDelegate.getInstance(); //业务层操作，不用关注
ResultSetIterator projectIterator = businessDelegate.
getProjectIterator(searchGene,pageSize);
java.util.List projects = projectIterator.getElements(page);
if (projects == null) {
projects = new java.util.ArrayList();
}
//将项目列表查询结果放置到请求对象中
request.removeAttribute(Constants.PROJECT_LISTFORM_KEY);
request.setAttribute(Constants.PROJECT_LISTFORM_KEY, projects);
//计算总页数
allSize = projectIterator.getAllSize();
pageCount = (allSize % pageSize == 0) ? allSize / pageSize :
allSize / pageSize + 1;
// System.err.print(pageCount);
form.set("pageCount", new Integer(pageCount));
//装载当前页面所需要现实小区信息
ResultSetIterator siteIterator = businessDelegate.getSitesIterator();
java.util.List sites = siteIterator.getElements(1);
request.getSession().setAttribute(Constants.SITE_LISTFORM_KEY,
sites);
//重定向到mapping中配置的input页面
// return actionMapping.findForward("success");
return actionMapping.getInputForward();
}
catch (Exception ex) {
com.ipbs.util.Log.println(
"[ProjectListSearchAction.java][Exception]:" + ex.getMessage());
ExceptionBean exception = new ExceptionBean();
exception.setErrorMsg(Constants.getExceptionMsg(ex));
exception.setReturnPath(actionMapping.findForward("failed.return").
getPath());
request.setAttribute(Constants.EXCEPTION_BEAN, exception);
return actionMapping.findForward("failed");
}
}
}
在上面的代码中，应用了一个常量类(Constants)，为了让大家看得更加明白，将其代码显示如下：
package com.ort.strutsdemo.simpledemo;
/**
* <p>Title: Struts Training </p>
* <p>Description: Struts内部培训Demo</p>
* <p>Copyright: Copyright (c) 2004</p>
* <p>Company: </p>
* @author Liuz
* @version 1.0
*/
public class Constants {
public static final String PROJECT_SINGLEFORM_KEY = "projectForm";
public static final String PROJECT_LISTFORM_KEY = "PROJECTS";
public static final String PROJECT_SEARCHFORM_KEY = "SEARCHPROJECTS";
public static final String PROJECT_CONTROLLERFORM_KEY = "PROJECTCONTROLLER";
public static final String SITE_LISTFORM_KEY = "SITES";
public static final String SITE_SINGLEFORM_KEY = "SITE";
public static final String EXCEPTION_BEAN = "EXCEPTIONBEAN";
/**
* 通过识别异常的基础类型，返回易懂的提示信息
* @param ex Exception 异常
* @return String 异常的描述信息
*/
public static final String getExceptionMsg(Exception ex){
String returnMsg="";
if(ex!=null){
if (ex instanceof com.boss.module.operation.command.exception.AlreadyExistException){
returnMsg = "数据已存在!";
return returnMsg;
}else if (ex instanceof com.boss.module.operation.command.exception.DbException){
returnMsg = "数据库错误!";
return returnMsg;
}else if(ex instanceof com.boss.module.operation.command.exception.InvalidObjectException){
returnMsg = "无效的数据!";
return returnMsg;
}else if(ex instanceof com.boss.module.operation.command.exception.InvalidPkException){
returnMsg = "无效的主键!";
return returnMsg;
}else if(ex instanceof com.boss.module.operation.command.exception.NotFoundException){
returnMsg = "数据不存在!";
return returnMsg;
}else if(ex instanceof com.boss.module.operation.command.exception.UnAuthorizationException){
returnMsg = "无权限!";
return returnMsg;
}else if(ex instanceof com.boss.module.operation.object.searchresult.exception.IteratorException){
returnMsg = "获取列表数据异常!";
return returnMsg;
}
}
return returnMsg;
}
}
