JavaWeb项目开发案例精粹-第3章在线考试系统-004Service层

1.

 package com.sanqing.service;

 import java.util.List;

 import com.sanqing.po.Student;

 public interface StudentService {
     //判断是否为合法学生，从而决定是否允许登录
     public boolean allowLogin(String studentID,String password);
     //获得学生信息
     public Student getStudentInfo(String studentID);
     //设置学生成绩
     public void setStudentResult(String studentID,int result);
     //根据学生姓名查找学生
     public List<Student> getStudentByName(String studentName);
     //根据班级查找学生
     public List<Student> getStudentByClass(String sclass);
 }

2.

 package com.sanqing.service;

 import java.util.List;

 import com.sanqing.dao.StudentDAO;
 import com.sanqing.dao.StudentDAOImpl;
 import com.sanqing.po.Student;

 public class StudentServiceImpl implements StudentService{
     private StudentDAO studentDAO = new StudentDAOImpl();

     public boolean allowLogin(String studentID, String password) {

         Student student = studentDAO.findByStudentID(studentID);
         if(student == null) {//判断是否存在该ID的学生
             return false;
         }else {
             if(password.equals(student.getPassword())) {//判断密码是否相同
                 return true;
             }else{
                 return false;
             }

         }
     }

     public Student getStudentInfo(String studentID) {
         return studentDAO.findByStudentID(studentID);
     }

     public void setStudentResult(String studentID, int result) {
         Student student = studentDAO.findByStudentID(studentID);//根据ID查找到该学生
         student.setResult(result);//设置其成绩
         studentDAO.updateStudent(student);//更新学生信息
     }

     public List<Student> getStudentByName(String studentName) {
         return studentDAO.findByStudentName(studentName);
     }

     public List<Student> getStudentByClass(String sclass) {
         return studentDAO.findByStudentClass(sclass);
     }
 }

3.

 package com.sanqing.service;

 import java.util.List;

 import com.sanqing.po.Subject;
 import com.sanqing.util.Page;
 import com.sanqing.util.PageResult;

 public interface SubjectService {
     // 添加试题，首先判断该试题标题是否已经存在，如果已经则不能添加
     public boolean saveSubject(Subject subject);
     // 按分页信息查询试题
     public PageResult querySubjectByPage(Page page);
     // 查看试题详细信息
     public Subject showSubjectParticular(int subjectID);
     // 更新试题信息
     public void updateSubject(Subject subject);
     // 删除试题信息
     public void deleteSubject(int subjectID);
     //模糊查询试题信息
     public PageResult likeQueryBySubjectTitle(String subjectTitle,Page page);
     //随机查询试题记录
     public List<Subject> randomFindSubject(int number);
     //计算学生得分
     public int accountResult(List<Integer> subjectIDs,List<String> studentAnswers);
 }

4.

 package com.sanqing.service;

 import java.util.List;

 import com.sanqing.dao.SubjectDAO;
 import com.sanqing.dao.SubjectDAOImpl;
 import com.sanqing.po.Subject;
 import com.sanqing.util.Page;
 import com.sanqing.util.PageResult;
 import com.sanqing.util.PageUtil;

 public class SubjectServiceImpl implements SubjectService{
     private SubjectDAO subjectDAO =  new SubjectDAOImpl();

     public boolean saveSubject(Subject subject) {
         String subjectTile = subject.getSubjectTitle();
         if(subjectDAO.findSubjectByTitle(subjectTile) == null){ //如果该试题标题不存在，允许添加
             subjectDAO.addSubject(subject);
             return true;
         }else {
             return false;
         }
     }

     public PageResult querySubjectByPage(Page page) {
         page = PageUtil.createPage(page.getEveryPage(),
                 subjectDAO.findSubjectCount(),page.getCurrentPage());//根据总记录数创建分页信息
         List<Subject> list = subjectDAO.findSubjectByPage(page);//通过分页信息取得试题
         PageResult result = new PageResult(page,list);//封装分页信息和记录信息，返回给调用处
         return result;
     }

     public Subject showSubjectParticular(int subjectID) {
         return subjectDAO.findSubjectByID(subjectID);
     }

     public void updateSubject(Subject subject) {
         subjectDAO.updateSubject(subject);
     }

     public void deleteSubject(int subjectID) {
         subjectDAO.deleteSubject(subjectID);
     }

     public PageResult likeQueryBySubjectTitle(String subjectTitle, Page page) {
         page = PageUtil.createPage(page.getEveryPage(),
                 subjectDAO.findLinkQueryCount(subjectTitle),page.getCurrentPage());//根据总记录数创建分页信息
         List<Subject> list = subjectDAO.likeQueryByTitle(subjectTitle, page);//通过分页信息模糊查询试题
         PageResult result = new PageResult(page,list);//封装分页信息和记录信息，返回给调用处
         return result;
     }

     public List<Subject> randomFindSubject(int number) {
         return subjectDAO.randomFindSubject(number);
     }

     public int accountResult(List<Integer> subjectIDs,
             List<String> studentAnswers) {
         int GeneralPoint = 0;//总分
         for(int i = 0; i < subjectIDs.size(); i++) {
             String rightAnswer = subjectDAO.
                 findSubjectByID(subjectIDs.get(i)).getSubjectAnswer();//得到正确答案，通过试题ID
             if(rightAnswer.equals(studentAnswers.get(i))) {
                 GeneralPoint += 5;//加5分
             }
         }
         return GeneralPoint;
     }
 }

5.

 package com.sanqing.service;

 public interface TeacherService {
     //判断是否为合法老师，从而决定是否允许登录
     public boolean allowLogin(String teacherID,String password);
 }

6.

 package com.sanqing.service;

 import com.sanqing.dao.TeacherDAO;
 import com.sanqing.dao.TeacherDAOImpl;
 import com.sanqing.po.Teacher;

 public class TeacherServiceImpl implements TeacherService{
     private TeacherDAO teacherDAO = new TeacherDAOImpl();

     public boolean allowLogin(String teacherID, String password) {
         Teacher teacher = teacherDAO.findByTeacherID(teacherID);
         if(teacher == null) {//判断是否存在该ID的教师
             return false;
         }else {
             if(password.equals(teacher.getPassword())) {//判断密码是否相同
                 return true;
             }else{
                 return false;
             }
         }
     }
 }