Java JDBC连接数据库并执行SQL操作的实战案例

原创 Love The Way You Lie 2024-09-06 01:15 80阅读 0赞

以下是一个简单的Java JDBC连接MySQL数据库，并执行SQL操作（例如，获取数据）的实战案例。请根据你的实际数据库和表结构进行调整。

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

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

public static void main(String[] args) {
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;

try {
            // 1. Connect to the database
            connection = DriverManager.getConnection(DB_URL, USER, PASS));

// 2. Create a statement for SQL execution
            statement = connection.createStatement();

// 3. Execute the SQL query (in this case, get all rows from a table)
            resultSet = statement.executeQuery("SELECT * FROM my_table");

// 4. Process the result set (fetch data and handle them as needed)
            while (resultSet.next()) {
                int id = resultSet.getInt("id");
                String name = resultSet.getString("name");

System.out.println("ID: " + id + ", Name: " + name);
            }

} catch (Exception e) {
            e.printStackTrace();
        } finally {
            // 5. Close all resources
            if (resultSet != null) {
                resultSet.close();
            }
            if (statement != null) {
                statement.close();
            }
            if (connection != null) {
                connection.close();
            }
        }

// Add any additional methods or logic here
}
```

请将上述代码中的数据库URL、用户名和密码替换为你的实际信息。同时，确保你的MySQL服务器已经启动并且监听3306端口。