编写Java程序访问数据表student,并显示表中的所有数据记录。
时间: 2024-05-01 21:23:15 浏览: 19
假设你已经有了连接数据库的代码和数据库连接对象`Connection conn`,可以按照以下步骤编写Java程序访问数据表student并显示表中的所有数据记录:
1. 创建查询语句字符串
```java
String query = "SELECT * FROM student";
```
2. 创建执行查询的`Statement`对象
```java
Statement stmt = conn.createStatement();
```
3. 执行查询并获取结果集
```java
ResultSet rs = stmt.executeQuery(query);
```
4. 遍历结果集并输出每条记录
```java
while (rs.next()) {
int id = rs.getInt("id");
String name = rs.getString("name");
int age = rs.getInt("age");
System.out.println("ID: " + id + ", Name: " + name + ", Age: " + age);
}
```
完整代码示例:
```java
import java.sql.*;
public class StudentTableReader {
public static void main(String[] args) {
Connection conn = null;
try {
// 连接数据库的代码
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb", "username", "password");
// 创建查询语句字符串
String query = "SELECT * FROM student";
// 创建执行查询的Statement对象
Statement stmt = conn.createStatement();
// 执行查询并获取结果集
ResultSet rs = stmt.executeQuery(query);
// 遍历结果集并输出每条记录
while (rs.next()) {
int id = rs.getInt("id");
String name = rs.getString("name");
int age = rs.getInt("age");
System.out.println("ID: " + id + ", Name: " + name + ", Age: " + age);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
// 关闭连接
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
}
```
注意:在实际代码中需要替换数据库连接信息,例如数据库URL、用户名和密码。