用Java和sql server做一个商品管理系统的程序

好的，以下是一个简单的商品管理系统的Java程序示例。该程序使用Java Swing作为GUI库，使用SQL Server作为后端数据库。

首先，我们需要创建一个数据库表来存储商品信息。以下是一个示例的SQL Server表定义：

CREATE TABLE products (
  id INT PRIMARY KEY IDENTITY,
  name VARCHAR(50) NOT NULL,
  price DECIMAL(10, 2) NOT NULL,
  quantity INT NOT NULL
);

然后，我们将使用Java JDBC API来连接SQL Server数据库并执行查询和更新操作。

import java.sql.*;

public class ProductManager {
  private static final String DB_URL = "jdbc:sqlserver://localhost:1433;databaseName=mydb;";
  private static final String USER = "myuser";
  private static final String PASS = "mypassword";

  public static void main(String[] args) {
    try (Connection conn = DriverManager.getConnection(DB_URL, USER, PASS)) {
      System.out.println("Connected to database!");

      // create a new product
      createProduct(conn, "iPhone 12 Pro", 999.99, 10);

      // print all products
      printProducts(conn);

      // update the price of a product
      updateProductPrice(conn, 1, 899.99);

      // delete a product
      deleteProduct(conn, 2);
    } catch (SQLException e) {
      System.out.println(e.getMessage());
    }
  }

  private static void createProduct(Connection conn, String name, double price, int quantity) throws SQLException {
    String sql = "INSERT INTO products(name, price, quantity) VALUES (?, ?, ?)";

    try (PreparedStatement statement = conn.prepareStatement(sql)) {
      statement.setString(1, name);
      statement.setDouble(2, price);
      statement.setInt(3, quantity);

      int rowsInserted = statement.executeUpdate();
      if (rowsInserted > 0) {
        System.out.println("A new product was inserted successfully!");
      }
    }
  }

  private static void printProducts(Connection conn) throws SQLException {
    String sql = "SELECT * FROM products";

    try (Statement statement = conn.createStatement();
         ResultSet result = statement.executeQuery(sql)) {

      while (result.next()) {
        int id = result.getInt("id");
        String name = result.getString("name");
        double price = result.getDouble("price");
        int quantity = result.getInt("quantity");

        System.out.println(id + ", " + name + ", " + price + ", " + quantity);
      }
    }
  }

  private static void updateProductPrice(Connection conn, int id, double price) throws SQLException {
    String sql = "UPDATE products SET price = ? WHERE id = ?";

    try (PreparedStatement statement = conn.prepareStatement(sql)) {
      statement.setDouble(1, price);
      statement.setInt(2, id);

      int rowsUpdated = statement.executeUpdate();
      if (rowsUpdated > 0) {
        System.out.println("The product was updated successfully!");
      }
    }
  }

  private static void deleteProduct(Connection conn, int id) throws SQLException {
    String sql = "DELETE FROM products WHERE id = ?";

    try (PreparedStatement statement = conn.prepareStatement(sql)) {
      statement.setInt(1, id);

      int rowsDeleted = statement.executeUpdate();
      if (rowsDeleted > 0) {
        System.out.println("The product was deleted successfully!");
      }
    }
  }
}

这个程序使用`createProduct`方法来创建一个新的商品，使用`printProducts`方法来打印所有商品，使用`updateProductPrice`方法来更新商品价格，使用`deleteProduct`方法来删除商品。这些方法都使用Java JDBC API来执行SQL查询和更新操作。

注意，为了运行这个程序，你需要下载并安装SQL Server JDBC驱动程序，并将其添加到你的Java类路径中。

这只是一个简单的示例程序，你可能需要根据你的具体需求进行修改和扩展。希望这可以帮助到你。