gradebean.java

在线教育平台： 从小学

package edu;

import java.sql.*;

public class GradeBean {
	private int id;

	private String grade;

	public void setId(int id) {
		this.id = id;
	}

	public int getId() {
		return id;
	}

	public void setGrade(String grade) {
		this.grade = grade;
	}

	public String getGrade() {
		return grade;
	}

	public ResultSet getGrades() {
		String sql = "select * from grade";
		SqlBean db = new SqlBean();
		ResultSet rs = db.executeQuery(sql);
		return rs;
	}

	public ResultSet getGrades(int id) {
		String sql = "select * from grade where grade_id='" + id + "'";
		SqlBean db = new SqlBean();
		ResultSet rs = db.executeQuery(sql);
		return rs;
	}

	public void updateGrade() {

		String sql = "update grade " + " set grade='" + grade
				+ "' where grade_id='" + id + "' ";
		SqlBean db = new SqlBean();
		db.executeInsert(sql);

	}

	public void deleteGrade() {

		String sql = "delete  from grade where grade_id ='" + id + "' ";
		SqlBean db = new SqlBean();
		db.executeDelete(sql);
	}

	public int deleteGrade(int id) {
		int num = 0;
		String sqlgrade = "delete  from grade where grade_id ='" + id + "' ";
		String sqlclass = "delete  from class where grade_id ='" + id + "' ";
		String sqlsubject = "delete  from subject where grade_id ='" + id
				+ "' ";
		SqlBean db = new SqlBean();
		db.executeDelete(sqlsubject);
		db.executeDelete(sqlclass);
		num = db.executeDelete(sqlgrade);
		return num;
	}

	public void addGrade() {
		String sql = "insert into grade(grade)  " + "VALUES('" + grade + "')";
		SqlBean db = new SqlBean();

		db.executeInsert(sql);
	}
}