Java如何移至绝对行或相对行？
在此示例中，我们向您展示如何使用结果集absolute()和relative()方法从一个结果集行跳转到另一行。当您传递正数作为参数时，您将从第一条记录移至最后一条记录。但是，如果您传递负数作为参数，则会从最后一条记录向后移动。
package org.nhooo.example.jdbc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class MoveAbsoluteOrRelativeExample {
private static final String URL = "jdbc:mysql://localhost/nhooo";
private static final String USERNAME = "root";
private static final String PASSWORD = "";
public static void main(String[] args) {
try (Connection connection =
DriverManager.getConnection(URL, USERNAME, PASSWORD)) {
Statement statement = connection.createStatement(
ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_READ_ONLY);
String sql = "SELECT code, name, price FROM products";
ResultSet rs = statement.executeQuery(sql);
//移至第二行
rs.absolute(2);
System.out.println("You are now in: " + rs.getRow());
//从当前位置向前移动2条记录
//（第四行）
rs.relative(2);
System.out.println("You are now in: " + rs.getRow());
//移至结果集中的最后一行
rs.absolute(-1);
System.out.println("You are now in: " + rs.getRow());
//从当前位置向后移动3条记录
//（第二行）
rs.relative(-3);
System.out.println("You are now in: " + rs.getRow());
} catch (SQLException e) {
e.printStackTrace();
}
}
}该代码输出以下结果：
You are now in: 2 You are now in: 4 You are now in: 5 You are now in: 2
Maven依赖
<!-- https://search.maven.org/remotecontent?filepath=mysql/mysql-connector-java/8.0.17/mysql-connector-java-8.0.17.jar -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.17</version>
</dependency>