stubean.java

针对数据库操作制作的一个学生管理系统

package Cstudent;

import java.util.*;
import java.sql.*;
import javax.swing.*;

/**
 * 有关学生信息数据库操作的类
 */
public class StuBean {
	String sql;
	ResultSet rs = null;
	
	String Sno;
	String Sname;
	String Ssex;
	String Sage;
	String Sdept;
	

	String colName;//列名
	String colValue;//列值
	String colValue2;//列值

	int stuId;//学生的新学号
	
	/**
	 * 添加学生信息
	 */	
	public void stuAdd(String sno, String name, String sex, String age, String sdept ){
		
		Database DB = new Database();
		
		this.Sno = sno;
		this.Sname = name;
		this.Ssex = sex;
		this.Sage = age;
		this.Sdept = sdept;
		
		if(Sname == null||Sname.equals("")){
			JOptionPane.showMessageDialog(null, "请输入学生姓名", "错误", JOptionPane.ERROR_MESSAGE);
			return;
		}
		else{
			sql = "insert into Student(Sno,Sname,Ssex,Sage,Sdept) values ('"+Sno+"','"+Sname+"','"+Ssex+"','"+Sage+"','"+Sdept+"')";
            try{
				DB.OpenConn();
				DB.executeUpdate(sql);
				JOptionPane.showMessageDialog(null,"成功添加一条新的纪录！");

			}
			catch(Exception e){
				System.out.println(e);
				JOptionPane.showMessageDialog(null, "保存失败", "错误", JOptionPane.ERROR_MESSAGE); 
			}
			finally {
				DB.closeStmt();
				DB.closeConn();
			}
		}
	}

	/**
	 * 修改学生信息
	 */
	public void stuModify(String sno, String name, String sex, String age, String sdept){
		
		Database DB = new Database();
		
		this.Sno = sno;
		this.Sname = name;
		this.Ssex = sex;
		this.Sage = age;
		this.Sdept = sdept;
		
		if(Sname == null||Sname.equals("")){
			JOptionPane.showMessageDialog(null, "请输入学生姓名", "错误", JOptionPane.ERROR_MESSAGE);
			return;
		}
		else{
			sql = "update Student set Sname = '"+Sname+"', Ssex = '"+Ssex+"', Sage = '"+Sage+"', Sdept = '"+Sdept+"' where Sno = "+Integer.parseInt(Sno)+"";
			try{
				DB.OpenConn();
				DB.executeUpdate(sql);
				JOptionPane.showMessageDialog(null,"成功修改一条新的纪录！");
			}
			catch(Exception e){
				System.out.println(e);
				JOptionPane.showMessageDialog(null, "更新失败", "错误", JOptionPane.ERROR_MESSAGE); 
			}
			finally {
				DB.closeStmt();
				DB.closeConn();
			}
		}
	}

	/**
	 * 删除学生信息
	 */
	public void stuDel(String sno){
		
		Database DB = new Database();
		this.Sno = sno;
		
		sql = "delete from Student where Sno = "+Integer.parseInt(Sno)+"";
		try{
			DB.OpenConn();
			DB.executeUpdate(sql);
			JOptionPane.showMessageDialog(null,"成功删除一条新的纪录！");
		}
		catch(Exception e){
			System.out.println(e);
			JOptionPane.showMessageDialog(null, "删除失败", "错误", JOptionPane.ERROR_MESSAGE); 
		}
		finally {
			DB.closeStmt();
			DB.closeConn();
		}
	}

	/**
	 * 根据学号查询学生信息
	 */
	public String[] stuSearch(String sno){
		
		Database DB = new Database();
		this.Sno = sno;
		String[] s = new String[8];
		sql = "select * from Student where Sno = "+Integer.parseInt(Sno)+"";

		try{
			DB.OpenConn();
			rs = DB.executeQuery(sql);
			if(rs.next()){
				s[0] = rs.getString("Sname");
				s[1] = rs.getString("Ssex");
				s[2] = rs.getString("Sage");
				s[3] = rs.getString("Sdept");
				
			}
			else
				s = null;
		}
		catch(Exception e){
		}
		finally {
			DB.closeStmt();
			DB.closeConn();
		}
		return s;
	}

	/**
	 * 学生信息综合查询(按照一个条件进行查询)
	 */
	public String[][] stuAllSearch(String colname,String colvalue){
		this.colName = colname;
		this.colValue = colvalue;

		Database DB = new Database();
		String[][] sn = null;
		int row = 0;
		int i = 0;

		DB.toGBK(colvalue);
		
		if(colValue == null||colValue.equals("")){
			sql = "select * from Student";
		}
		else{
			sql = "select * from Student where "+colName+" = '"+colValue+"'";
		}
		try{
			DB.OpenConn();
			rs = DB.executeQuery(sql);

			if(rs.last()){
				row = rs.getRow();
			}
			
			if(row == 0){
				sn = null;
			}
			else{
				sn = new String[row][9];
				rs.first();
				rs.previous();
				while(rs.next()){
					sn[i][0] = rs.getString("Sno");
					sn[i][1] = rs.getString("Sname");
					sn[i][2] = rs.getString("Ssex");
					sn[i][3] = rs.getString("Sage");
					sn[i][4] = rs.getString("Sdept");
					i++;
				}
			}
		}
		catch(Exception e){
		}
		finally {
			DB.closeStmt();
			DB.closeConn();
		}
		return sn;
	}

	/**
	 * 学生信息综合查询(查询某范围内的记录)
	 */
	public String[][] stuAllSearch(String colname,String colvalue,String colvalue2){
		this.colName = colname;
		this.colValue = colvalue;
		this.colValue2 = colvalue2;
		
		Database DB = new Database();
		String[][] sn = null;
		int row = 0;
		int i = 0;
		sql = "select * from Student where "+colName+" between "+colValue+" and "+colValue2+"";
		try{
			DB.OpenConn();
			rs = DB.executeQuery(sql);

			if(rs.last()){
				row = rs.getRow();
			}
			
			if(row == 0){
				sn = null;
			}
			else{
				sn = new String[row][9];
				rs.first();
				rs.previous();
				while(rs.next()){
					sn[i][0] = rs.getString("Sno");
					sn[i][1] = rs.getString("Sname");
					sn[i][2] = rs.getString("Ssex");
					sn[i][3] = rs.getString("Sage");
					sn[i][4] = rs.getString("Sdept");
					i++;
				}
			}
		}
		catch(Exception e){
		}
		finally {
			DB.closeStmt();
			DB.closeConn();
		}
		return sn;
	}
	/**
	 * 获得新的学号
	 */
	public int getStuId(){
		Database DB = new Database();
		sql = "select max(Sno) from Student";
		try{
			DB.OpenConn();
			rs = DB.executeQuery(sql);
			if(rs.next()){
				stuId = rs.getInt(1) + 1;
			}
			else
				stuId = 1;
		}
		catch(Exception e){
		}
		finally {
			DB.closeStmt();
			DB.closeConn();
		}
		return stuId;
	}


	
	
	/**
	 * 获得Student表中的所有学号Sno
	 */
	public String[] getAllId(){
		String[] s = null;
		int row = 0;
		int i = 0;
		Database DB = new Database();
		sql = "select Sno from Student";
		
		try{
			DB.OpenConn();
			rs = DB.executeQuery(sql);
			if(rs.last()){
				row = rs.getRow();
			}

			if(row == 0){
				s = null;
			}
			else{
				s = new String[row];
				rs.first();
				rs.previous();
				while(rs.next()){
					s[i] = rs.getString(1);
					i++;
				}
			}
		}
		catch(Exception e){
			System.out.println(e);
		}
		finally {
			DB.closeStmt();
			DB.closeConn();
		}
		return s;
	}
}