daoimplement.courseDao.java Source code

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Here is the source code for daoimplement.courseDao.java

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/*
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 */
package daoimplement;

import model.Course;
import daointerface.courseInterface;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.springframework.orm.hibernate4.HibernateTemplate;

/**
 *
 * @author Administrator
 */
public class courseDao implements courseInterface<Course> {

    HibernateTemplate template;

    public void setTemplate(HibernateTemplate template) {
        this.template = template;
    }

    //Get new course ID to create a new Course row
    @Override
    public int getNewCourseID() {

        String hql = "SELECT max(course_id) FROM Course";

        List<Object> Id = template.find(hql); //query.list();

        int curID = 1;
        if (!(Id.get(0) == null)) {

            curID = (Integer) Id.get(0) + 1;
        }

        return curID;

    }

    //insert a new record
    @Override
    public void insert(Course entity) {
        template.save(entity);
        System.out.println("Called save(course)");
    }

    // update a record
    @Override
    public void update(Course entity) {
        template.update(entity);
    }

    // Select a course that has course_id  = id
    @Override
    public Course selectById(int id) {

        Course crs = template.get(Course.class, id);

        return crs;
    }

    //Delete a course
    @Override
    public void delete(Course course) {
        template.delete(course);
    }

    //Select all course in Course table
    @Override
    public List<Course> select() {

        List<Course> students = template.loadAll(Course.class);
        return students;
    }

    //Write all data of Course Table to a text file named filename
    @Override
    public void write_to_file(String filename) {

        //Create a file
        File file = new File(filename);
        if (!file.exists()) {
            File citydir = new File(file.getParent());
            if (!citydir.exists())
                citydir.mkdirs();

            try {
                file.createNewFile();
            } catch (IOException ex) {
                Logger.getLogger(courseDao.class.getName()).log(Level.SEVERE, null, ex);
            }
        }

        //Get information from Database

        List<Course> courses = template.loadAll(Course.class);

        //write to file
        PrintWriter fout = null;
        try {
            fout = new PrintWriter(new BufferedWriter(new FileWriter(file)));

            for (Course crs : courses) {
                int course_id = crs.getCourse_id();
                String course_name = crs.getCourse_name();

                fout.println(course_id + "," + course_name);
            }
            fout.close();
        } catch (IOException ex) {
            Logger.getLogger(courseDao.class.getName()).log(Level.SEVERE, null, ex);
        }

    }

    ////Import all data of Course Table from a text file named filename
    @Override
    public void insert_from_file(String filename) {
        File file = new File(filename);
        BufferedReader fin = null;

        if (!file.exists()) {
            System.out.println("File not exists!");
        } else {
            System.out.println("Insert data from file ....");

            try {
                fin = new BufferedReader(new FileReader(file));
                String line = null;
                line = fin.readLine();
                while (line != null) {
                    //slipt line data and add fields to Person object 

                    String[] components = line.split(",");
                    int course_id = Integer.parseInt(components[0]);
                    String course_name = components[1];

                    Course course = new Course(course_id, course_name);

                    //insert to database
                    this.insert(course);

                    //read next line
                    line = fin.readLine();

                }

                //close file           
                fin.close();

                System.out.println("end of inserting");

            } catch (IOException ex) {
                Logger.getLogger(courseDao.class.getName()).log(Level.SEVERE, null, ex);
            }

        }
    }

}