由java和sql server技术编写出来的一个简单的学生课程管理系统，实现增、删、查、改等功能。以窗体的方式实现，需要完整代码和步骤。

好的，以下是一个简单的学生课程管理系统的Java代码和SQL Server数据库操作步骤。

Java代码：

import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import javax.swing.*;

public class StudentCourseManagementSystem extends JFrame implements ActionListener {
    JLabel nameLabel, courseLabel, gradeLabel;
    JTextField nameField, courseField, gradeField;
    JButton addButton, deleteButton, updateButton, searchButton;
    JTable table;
    DefaultTableModel model;

    public StudentCourseManagementSystem() {
        super("学生课程管理系统");
        setLayout(null);
        setSize(550, 400);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        nameLabel = new JLabel("姓名:");
        nameLabel.setBounds(20, 20, 50, 20);
        add(nameLabel);

        nameField = new JTextField();
        nameField.setBounds(80, 20, 100, 20);
        add(nameField);

        courseLabel = new JLabel("课程:");
        courseLabel.setBounds(200, 20, 50, 20);
        add(courseLabel);

        courseField = new JTextField();
        courseField.setBounds(260, 20, 100, 20);
        add(courseField);

        gradeLabel = new JLabel("成绩:");
        gradeLabel.setBounds(380, 20, 50, 20);
        add(gradeLabel);

        gradeField = new JTextField();
        gradeField.setBounds(440, 20, 50, 20);
        add(gradeField);

        addButton = new JButton("添加");
        addButton.setBounds(20, 60, 80, 20);
        addButton.addActionListener(this);
        add(addButton);

        deleteButton = new JButton("删除");
        deleteButton.setBounds(120, 60, 80, 20);
        deleteButton.addActionListener(this);
        add(deleteButton);

        updateButton = new JButton("更新");
        updateButton.setBounds(220, 60, 80, 20);
        updateButton.addActionListener(this);
        add(updateButton);

        searchButton = new JButton("查找");
        searchButton.setBounds(320, 60, 80, 20);
        searchButton.addActionListener(this);
        add(searchButton);

        model = new DefaultTableModel();
        table = new JTable(model);
        JScrollPane pane = new JScrollPane(table);
        pane.setBounds(20, 100, 500, 250);
        add(pane);

        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == addButton) {
            addRecord();
        } else if (e.getSource() == deleteButton) {
            deleteRecord();
        } else if (e.getSource() == updateButton) {
            updateRecord();
        } else if (e.getSource() == searchButton) {
            searchRecord();
        }
    }

    public void addRecord() {
        String name = nameField.getText();
        String course = courseField.getText();
        String grade = gradeField.getText();

        if (name.equals("") || course.equals("")) {
            JOptionPane.showMessageDialog(null, "姓名和课程不能为空！");
            return;
        }

        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
            Connection conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=StudentCourseDB;user=sa;password=123456");
            Statement stmt = conn.createStatement();
            String sql = "INSERT INTO StudentCourseTable VALUES ('" + name + "', '" + course + "', '" + grade + "')";
            stmt.executeUpdate(sql);
            JOptionPane.showMessageDialog(null, "添加成功！");
            nameField.setText("");
            courseField.setText("");
            gradeField.setText("");
            conn.close();
        } catch (Exception ex) {
            JOptionPane.showMessageDialog(null, ex.getMessage());
        }
    }

    public void deleteRecord() {
        int selectedRow = table.getSelectedRow();

        if (selectedRow == -1) {
            JOptionPane.showMessageDialog(null, "请选择要删除的记录！");
            return;
        }

        String name = (String) model.getValueAt(selectedRow, 0);
        String course = (String) model.getValueAt(selectedRow, 1);

        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
            Connection conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=StudentCourseDB;user=sa;password=123456");
            Statement stmt = conn.createStatement();
            String sql = "DELETE FROM StudentCourseTable WHERE Name='" + name + "' AND Course='" + course + "'";
            stmt.executeUpdate(sql);
            JOptionPane.showMessageDialog(null, "删除成功！");
            conn.close();
            model.removeRow(selectedRow);
        } catch (Exception ex) {
            JOptionPane.showMessageDialog(null, ex.getMessage());
        }
    }

    public void updateRecord() {
        int selectedRow = table.getSelectedRow();

        if (selectedRow == -1) {
            JOptionPane.showMessageDialog(null, "请选择要更新的记录！");
            return;
        }

        String name = (String) model.getValueAt(selectedRow, 0);
        String course = (String) model.getValueAt(selectedRow, 1);
        String grade = (String) model.getValueAt(selectedRow, 2);

        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
            Connection conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=StudentCourseDB;user=sa;password=123456");
            Statement stmt = conn.createStatement();
            String sql = "UPDATE StudentCourseTable SET Grade='" + grade + "' WHERE Name='" + name + "' AND Course='" + course + "'";
            stmt.executeUpdate(sql);
            JOptionPane.showMessageDialog(null, "更新成功！");
            conn.close();
        } catch (Exception ex) {
            JOptionPane.showMessageDialog(null, ex.getMessage());
        }
    }

    public void searchRecord() {
        String name = nameField.getText();
        String course = courseField.getText();

        try {
            Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
            Connection conn = DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=StudentCourseDB;user=sa;password=123456");
            Statement stmt = conn.createStatement();
            String sql = "SELECT * FROM StudentCourseTable WHERE Name='" + name + "' OR Course='" + course + "'";
            ResultSet rs = stmt.executeQuery(sql);
            model.setRowCount(0);

            while (rs.next()) {
                String[] rowData = {rs.getString("Name"), rs.getString("Course"), rs.getString("Grade")};
                model.addRow(rowData);
            }

            conn.close();
        } catch (Exception ex) {
            JOptionPane.showMessageDialog(null, ex.getMessage());
        }
    }

    public static void main(String[] args) {
        new StudentCourseManagementSystem();
    }
}

SQL Server数据库操作步骤：

1. 创建一个新的数据库，命名为StudentCourseDB。

2. 在该数据库中创建一个名为StudentCourseTable的表格，包含三个列：Name、Course和Grade。

3. 将以下SQL语句复制并执行，插入一些测试数据：

   INSERT INTO StudentCourseTable VALUES ('张三', '数学', '90');
   INSERT INTO StudentCourseTable VALUES ('李四', '英语', '80');
   INSERT INTO StudentCourseTable VALUES ('王五', '历史', '70');

数据库表格应该长这样：

| Name | Course | Grade |
| ---- | ------ | ----- |
| 张三 | 数学 | 90 |
| 李四 | 英语 | 80 |
| 王五 | 历史 | 70 |

4. 使用SQL Server Management Studio连接数据库，确保数据库连接信息（主机名、端口号、用户名、密码）与Java代码中的一致。

5. 运行Java代码，即可使用学生课程管理系统。