java显示数据库表中的内容
时间: 2024-01-22 13:21:31 浏览: 21
要在Java中显示数据库表中的内容,您可以使用Java JDBC API来连接到数据库并执行查询。以下是一个简单的示例代码,它连接到MySQL数据库并显示"employees"表中的数据:
```java
import java.sql.*;
public class DisplayTableData {
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;
try {
// Register JDBC driver
Class.forName("com.mysql.jdbc.Driver");
// Open a connection
System.out.println("Connecting to database...");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "username", "password");
// Execute a query
System.out.println("Creating statement...");
stmt = conn.createStatement();
String sql = "SELECT * FROM employees";
rs = stmt.executeQuery(sql);
// Extract data from result set
while (rs.next()) {
// Retrieve by column name
int id = rs.getInt("id");
String name = rs.getString("name");
int age = rs.getInt("age");
String address = rs.getString("address");
// Display values
System.out.print("ID: " + id);
System.out.print(", Name: " + name);
System.out.print(", Age: " + age);
System.out.println(", Address: " + address);
}
} catch (SQLException se) {
// Handle errors for JDBC
se.printStackTrace();
} catch (Exception e) {
// Handle errors for Class.forName
e.printStackTrace();
} finally {
// Close resources
try {
if (rs != null) rs.close();
if (stmt != null) stmt.close();
if (conn != null) conn.close();
} catch (SQLException se) {
se.printStackTrace();
}
}
}
}
```
在上面的示例中,您需要将“username”和“password”替换为您自己的MySQL数据库用户名和密码。您还需要将“test”替换为您要连接的数据库名称。
运行上面的代码将显示“employees”表中的所有数据。您可以根据需要修改查询以显示特定的列或行。