Java JDBC连接数据库问题实例

原创比眉伴天荒 2024-12-04 22:57 26阅读 0赞

在Java中使用JDBC（Java Database Connectivity）来连接数据库，通常需要以下步骤和一个实例：

1. **导入库**：首先在项目中引入相关的JDBC驱动，例如MySQL的JDBC驱动是`mysql-connector-java.jar`。

2. **建立连接**：创建`Connection`对象是与数据库交互的关键。示例代码如下：

```java
import java.sql.Connection;
import java.sql.DriverManager;

public class DatabaseConnection {
    private static final String DB_URL = "jdbc:mysql://localhost:3306/mydatabase";
    private static final String USER = "username";
    private static final String PASS = "password";

public static Connection getConnection() {
        try {
            Connection connection = DriverManager.getConnection(DB_URL, USER, PASS));
            System.out.println("Connected to Database");
            return connection;
        } catch (Exception e) {
            e.printStackTrace();
            return null; // Return null if connection fails
        }
    }

public static void main(String[] args) {
        Connection connection = getConnection();
        if (connection != null) {
            try {
                // Perform operations on the connected database
                // For example, creating a table:
                String createTableSQL = "CREATE TABLE Employees (" +
                        "ID INT AUTO_INCREMENT," +
                        "Name VARCHAR(50)," +
                        "Position VARCHAR(10))" +
                        ";";
                connection.createStatement().execute(createTableSQL));
                System.out.println("Table created successfully.");
            } catch (Exception e) {
                System.err.println("Error in database operation: " + e.getMessage());
                e.printStackTrace();
            }
        } else {
            System.out.println("Failed to connect to the database.");
        }

connection.close(); // Close the connection when done
    }
}
```

这个实例中，我们连接了一个MySQL数据库，并创建了一个名为`Employees`的表。如果连接成功，你将在控制台看到相应的操作结果和提示信息。