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;
            }
        }
    }
}