使用中文解释ssm管理系统文件中util文件里PageHelper类解释以下代码package com.util; import java.util.ArrayList; import java.util.List; import javax.servlet.http.HttpServletRequest; public class PageHelper { public static void getPage(List<?> list, String name, List<String> nameList, List<String> valueList, int pageSize, String number, HttpServletRequest request, String method) { StringBuffer buffer = new StringBuffer(); String name2 = name.substring(0, 1).toUpperCase() + name.substring(1); String path = ""; String action = "getAll" + name2 + ".action"; if (method != null) { action = "query" + name2 + "ByCond.action"; } List<Object> objList = new ArrayList<Object>(); if (nameList != null && valueList != null) { for (int i = 0; i < nameList.size(); i++) { path += "&" + nameList.get(i) + "=" + valueList.get(i); } } int pageNumber = list.size(); int maxPage = pageNumber; if (maxPage % pageSize == 0) { maxPage = maxPage / pageSize; } else { maxPage = maxPage / pageSize + 1; } if (number == null) { number = "0"; } int start = Integer.parseInt(number) * pageSize; int over = (Integer.parseInt(number) + 1) * pageSize; int count = pageNumber - over; if (count <= 0) { over = pageNumber; } for (int i = start; i < over; i++) { Object obj = list.get(i); objList.add(obj); } buffer.append(" 共为"); buffer.append(maxPage); buffer.append("页 共有"); buffer.append(pageNumber); buffer.append("条 当前为第"); buffer.append((Integer.parseInt(number) + 1)); buffer.append("页 "); if ((Integer.parseInt(number) + 1) == 1) { buffer.append("首页"); } else { buffer.append("<a href="" + name + "/" + action + "?number=0" + path + "">首页</a>"); } buffer.append(" "); if ((Integer.parseInt(number) + 1) == 1) { buffer.append("上一页"); } else { buffer.append("<a href="" + name + "/" + action + "?number=" + (Integer.parseInt(number) - 1) + "" + path + "">上一页</a>"); } buffer.append(" "); if (maxPage <= (Integer.parseInt(number) + 1)) { buffer.append("下一页"); } else { buffer.append("<a href="" + name + "/" + action + "?number=" + (Integer.parseInt(number) + 1) + "" + path + "">下一页</a>"); } buffer.append(" "); if (maxPage <= (Integer.parseInt(number) + 1)) { buffer.append("尾页"); } else { buffer.append("<a href="" + name + "/" + action + "?number=" + (maxPage - 1) + "" + path + "">尾页</a>"); } String html = buffer.toString(); request.setAttribute("html", html); request.setAttribute(name + "List", objList); }

该代码是一个用于分页的工具类，主要包含一个静态方法getPage。该方法有以下参数：

- list: 需要分页的数据列表
- name: 数据对应的实体类名称
- nameList: 分页链接的参数名列表
- valueList: 分页链接的参数值列表
- pageSize: 每页显示的数据数量
- number: 当前页码
- request: HTTP请求对象
- method: 查询方法名

该方法的作用是根据传入的参数，生成分页链接，并将生成的链接添加到HTTP请求对象中。在生成分页链接时，会根据传入的参数生成对应的查询字符串，并将其添加到链接中。其中，name2是将实体类名称的首字母大写后的结果。path是请求路径，action是请求的动作。如果传入了method参数，则动作为"query"+name2+"ByCond.action"，否则动作为"getAll"+name2+".action"。objList是一个空的对象列表，暂时没有被使用。

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使用中文解释ssm管理系统文件action文件里的以下代码package com.action; import java.util.ArrayList; import java.util.List; import javax.annotation.Resource; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import com.entity.Marks; import com.entity.Programs; import com.entity.Student; import com.entity.Teacher; import com.service.MarksService; import com.service.ProgramsService; import com.service.StudentService; import com.service.TeacherService; import com.util.PageHelper; import com.util.VeDate; //定义为控制器 @Controller // 设置路径 @RequestMapping(value = "/marks", produces = "text/plain;charset=utf-8") public class MarksAction extends BaseAction { // 注入Service 由于标签的存在 所以不需要getter setter @Autowired @Resource private MarksService marksService; @Autowired @Resource private TeacherService teacherService; @Autowired @Resource private StudentService studentService; @Autowired @Resource private ProgramsService programsService; // 准备添加数据 @RequestMapping("createMarks.action") public String createMarks() { List<Student> studentList = this.studentService.getAllStudent(); this.getRequest().setAttribute("studentList", studentList); List<Programs> programsList = this.programsService.getAllPrograms(); this.getRequest().setAttribute("programsList", programsList); return "addmarks"; } // 添加数据 @RequestMapping("addMarks.action") public String addMarks(Marks marks) { double total = 0; List<Programs> programsList = this.programsService.getAllPrograms(); for (Programs p : programsList) { String pnum = this.getRequest().getParameter("num_" + p.getProgramsid()); System.out.println(pnum); total += Double.parseDouble(pnum); } String teacherid = (String) this.getSession().getAttribute("teacherid"); marks.setTeacherid(teacherid); marks.setAddtime(VeDate.getStringDateShort()); marks.setScore("" + VeDate.getDouble(total)); this.marksService.insertMarks(marks); return "redirect:/marks/createMarks.action"; }

这是一个使用 Spring MVC 框架开发的 SSM 管理系统中的 Action 文件，主要用于处理成绩相关的请求。在代码中，首先引入了一些依赖包和类，包括 ArrayList、List、Resource、Autowired、Controller、RequestMapping 等等。其中，@Controller 注解表示将该类定义为控制器，@RequestMapping 注解表示设置路径。

接下来，通过 @Autowired 和 @Resource 注解来注入 Service，即注入业务逻辑处理类，包括 MarksService、TeacherService、StudentService 和 ProgramsService。这些 Service 类中包含了对应的业务方法，用于处理查询、添加、修改和删除等操作。

在该 Action 中，通过 @RequestMapping 注解定义了两个请求处理方法：createMarks 和 addMarks。其中，createMarks 方法用于准备添加数据，即获取所有学生和课程信息，并将其设置到请求域中，最后返回一个字符串 "addmarks"，表示跳转到 addmarks.jsp 页面。而 addMarks 方法则用于添加数据，即获取表单中提交的成绩信息，计算总成绩，设置添加时间、教师 ID 和总成绩等属性，调用 marksService.insertMarks 方法将成绩信息插入到数据库中，最后返回一个字符串 "redirect:/marks/createMarks.action"，表示重定向到 createMarks 方法。

总之，该 Action 文件是 SSM 管理系统中成绩模块的控制器，用于处理成绩相关的请求，包括添加、查询和删除等操作。

ssm管理系统文件中util文件里PageHelper类解释以下代码package com.util; import java.util.ArrayList; import java.util.List; import javax.servlet.http.HttpServletRequest; public class PageHelper { public static void getPage(List<?> list, String name, List<String> nameList, List<String> valueList, int pageSize, String number, HttpServletRequest request, String method) { StringBuffer buffer = new StringBuffer(); String name2 = name.substring(0, 1).toUpperCase() + name.substring(1); String path = ""; String action = "getAll" + name2 + ".action"; if (method != null) { action = "query" + name2 + "ByCond.action"; } List<Object> objList = new ArrayList<Object>(); if (nameList != null && valueList != null) { for (int i = 0; i < nameList.size(); i++) { path += "&" + nameList.get(i) + "=" + valueList.get(i); } } int pageNumber = list.size(); int maxPage = pageNumber; if (maxPage % pageSize == 0) { maxPage = maxPage / pageSize; } else { maxPage = maxPage / pageSize + 1; } if (number == null) { number = "0"; } int start = Integer.parseInt(number) * pageSize; int over = (Integer.parseInt(number) + 1) * pageSize; int count = pageNumber - over; if (count <= 0) { over = pageNumber; } for (int i = start; i < over; i++) { Object obj = list.get(i); objList.add(obj); } buffer.append("&nbsp;&nbsp;共为"); buffer.append(maxPage); buffer.append("页&nbsp; 共有"); buffer.append(pageNumber); buffer.append("条&nbsp; 当前为第"); buffer.append((Integer.parseInt(number) + 1)); buffer.append("页 &nbsp;"); if ((Integer.parseInt(number) + 1) == 1) { buffer.append("首页"); } else { buffer.append("<a href=\"" + name + "/" + action + "?number=0" + path + "\">首页</a>"); } buffer.append("&nbsp;&nbsp;"); if ((Integer.parseInt(number) + 1) == 1) { buffer.append("上一页"); } else { buffer.append("<a href=\"" + name + "/" + action + "?number=" + (Integer.parseInt(number) - 1) + "" + path + "\">上一页</a>"); } buffer.append("&nbsp;&nbsp;"); if (maxPage <= (Integer.parseInt(number) + 1)) { buffer.append("下一页"); } else { buffer.append("<a href=\"" + name + "/" + action + "?number=" + (Integer.parseInt(number) + 1) + "" + path + "\">下一页</a>"); } buffer.append("&nbsp;&nbsp;"); if (maxPage <= (Integer.parseInt(number) + 1)) { buffer.append("尾页"); } else { buffer.append("<a href=\"" + name + "/" + action + "?number=" + (maxPage - 1) + "" + path + "\">尾页</a>"); } String html = buffer.toString(); request.setAttribute("html", html); request.setAttribute(name + "List", objList); }

The `PageHelper` class in the `util` package of the SSM management system is used to implement pagination functionality for displaying data in pages.

The `getPage` method takes the following parameters:

- `list`: the list of objects to be paginated
- `name`: the name of the entity being paginated
- `nameList`: a list of parameter names used for filtering the data
- `valueList`: a list of parameter values used for filtering the data
- `pageSize`: the number of objects to be displayed per page
- `number`: the current page number
- `request`: the HTTP servlet request object
- `method`: the name of the method used for filtering the data

The method first constructs the URL for the pagination links by appending the `action` parameter to the entity name. If a filter method is provided, it replaces the default `getAll` method with the filter method.

Next, it creates a new list to hold the paginated data and calculates the total number of pages based on the size of the original data list and the page size. It then adds the relevant parameters to the URL for each page and constructs the HTML code for the pagination links.

Finally, it sets the paginated data list and pagination HTML code as attributes of the request object to be passed back to the view for display.