courseinput.java

自己写的学生选课系统,多多关照.以后共同学习

package student;

import java.awt.BorderLayout;

import javax.swing.JFrame;
import javax.swing.JLabel;
import java.awt.Rectangle;
import java.awt.Font;
import javax.swing.BorderFactory;
import javax.swing.JTextField;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.*; //要使用到ResultSet所以要引入SQL 包
import java.awt.*;

public class CourseInput extends JFrame {
    public CourseInput() {
        try {
            jbInit();
        } catch (Exception exception) {
            exception.printStackTrace();
        }
    }

    private void jbInit() throws Exception {
        setTitle("课程录入");
        setSize(400, 330);
        setLocation(400, 300);
        setVisible(true);
        getContentPane().setLayout(null);
        jLabel1.setFont(new java.awt.Font("宋体", Font.BOLD, 22));
        jLabel1.setBorder(BorderFactory.createRaisedBevelBorder());
        jLabel1.setText("课程录入");
        jLabel1.setBounds(new Rectangle(144, 26, 100, 48));
        jLabel3.setText("课程名称：");
        jLabel3.setBounds(new Rectangle(197, 93, 63, 22));
        jTextFieldName.setBounds(new Rectangle(266, 92, 101, 23));
        jLabel4.setText("学  分：");
        jLabel4.setBounds(new Rectangle(19, 144, 49, 29));
        jTextFieldCredit.setBounds(new Rectangle(79, 145, 101, 24));
        jLabel5.setText("学  期：");
        jLabel5.setBounds(new Rectangle(205, 146, 48, 24));
        jTextFieldSemste.setBounds(new Rectangle(265, 144, 101, 24));
        jLabel6.setText("学  时：");
        jLabel6.setBounds(new Rectangle(23, 192, 50, 28));
        jTextFieldPeriod.setBounds(new Rectangle(79, 194, 102, 24));
        jLabel7.setText("授课老师：");
        jLabel7.setBounds(new Rectangle(195, 198, 74, 20));
        jTextFieldTeacher.setBounds(new Rectangle(265, 195, 99, 24));
        jTextFieldNum.setBounds(new Rectangle(79, 94, 101, 23));
        jButton1.setBounds(new Rectangle(82, 242, 87, 30));
        jButton1.setText("提交");
        jButton1.addActionListener(new CourseInput_jButton1_actionAdapter(this));
        jButton2.setBounds(new Rectangle(207, 243, 82, 31));
        jButton2.setText("重置");
        jButton2.addActionListener(new CourseInput_jButton2_actionAdapter(this));
        this.getContentPane().add(jLabel2);
        this.getContentPane().add(jTextFieldNum);
        this.getContentPane().add(jTextFieldCredit);
        this.getContentPane().add(jLabel3);
        this.getContentPane().add(jTextFieldName);
        this.getContentPane().add(jTextFieldSemste);
        this.getContentPane().add(jLabel6);
        this.getContentPane().add(jTextFieldPeriod);
        this.getContentPane().add(jLabel7);
        this.getContentPane().add(jLabel5);
        this.getContentPane().add(jLabel4);
        this.getContentPane().add(jTextFieldTeacher);
        this.getContentPane().add(jLabel1);
        this.getContentPane().add(jButton1);
        this.getContentPane().add(jButton2);
        jLabel2.setText("课程号：");
        jLabel2.setBounds(new Rectangle(22, 93, 65, 22));
    }

    JLabel jLabel1 = new JLabel();
    JLabel jLabel2 = new JLabel();
    JTextField jTextFieldNum = new JTextField();
    JLabel jLabel3 = new JLabel();
    JTextField jTextFieldName = new JTextField();
    JLabel jLabel4 = new JLabel();
    JTextField jTextFieldCredit = new JTextField();
    JLabel jLabel5 = new JLabel();
    JTextField jTextFieldSemste = new JTextField();
    JLabel jLabel6 = new JLabel();
    JTextField jTextFieldPeriod = new JTextField();
    JLabel jLabel7 = new JLabel();
    JTextField jTextFieldTeacher = new JTextField();
    JButton jButton1 = new JButton();
    JButton jButton2 = new JButton();
    public void jButton1_actionPerformed(ActionEvent e) {

        if (jTextFieldNum.getText().trim().equals("")) {
            JOptionPane.showMessageDialog(this, "课程号不能为空");
        }
        //检查课程名是否为空
        if (jTextFieldNum.getText().trim().equals("")) {
            JOptionPane.showMessageDialog(this, "课程名不能为空");
        }
        //查询课程是否已经存在
        String sql = "select *from Course where Cno = '" +
                     jTextFieldNum.getText().trim() + "'";

        System.out.println(sql); //在控制台输出sql语句 以便调试
        ResultSet rs = DBManager.getResult(sql); //返回结果集
        try {
            if (rs.next()) {
                JOptionPane.showMessageDialog(this, "课程已经存在");
            } else {
                sql =
                        "insert into Course(Cno,Cname,Ccredit,Semester,Period,Teacher)  values('"
                        + jTextFieldNum.getText().trim() + "','"
                        + jTextFieldName.getText().trim() + "',"
                        + Float.parseFloat(jTextFieldCredit.getText().trim()) +
                        ","
                        + Integer.parseInt(jTextFieldSemste.getText().trim()) +
                        ",'"
                        + jTextFieldPeriod.getText().trim() + "','"
                        + jTextFieldTeacher.getText().trim() + "')";
                System.out.println(sql); //在控制台输出sql语句 以便调试

                if (DBManager.executeSql(sql)) {
                    JOptionPane.showMessageDialog(this, "课程录入成功！");
                } else {
                    JOptionPane.showMessageDialog(this, "课程录入失败！");
                }

            }

        } catch (SQLException ex) {
        }

    }

    //清空方法
    public void setNull() {
        jTextFieldNum.setText(null);
        jTextFieldName.setText(null);
        jTextFieldCredit.setText(null);
        jTextFieldSemste.setText(null);
        jTextFieldPeriod.setText(null);
        jTextFieldTeacher.setText(null);
    }

    public void jButton2_actionPerformed(ActionEvent e) {
        setNull(); //清空方法
    }
}


/***********************下面为监听类*******************************/
class CourseInput_jButton2_actionAdapter implements ActionListener {
    private CourseInput adaptee;
    CourseInput_jButton2_actionAdapter(CourseInput adaptee) {
        this.adaptee = adaptee;
    }

    public void actionPerformed(ActionEvent e) {
        adaptee.jButton2_actionPerformed(e);
    }
}


class CourseInput_jButton1_actionAdapter implements ActionListener {
    private CourseInput adaptee;
    CourseInput_jButton1_actionAdapter(CourseInput adaptee) {
        this.adaptee = adaptee;
    }

    public void actionPerformed(ActionEvent e) {
        adaptee.jButton1_actionPerformed(e);
    }
}