java更新mysql语句怎么写

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

public class UpdateExample {
    // 数据库连接信息
    static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";
    static final String DB_URL = "jdbc:mysql://localhost/yourdatabase";
    static final String USER = "username";
    static final String PASS = "password";

    public static void main(String[] args) {
        Connection conn = null;
        PreparedStatement pstmt = null;
        try {
            // 注册JDBC驱动
            Class.forName(JDBC_DRIVER);

            // 打开连接
            System.out.println("Connecting to database...");
            conn = DriverManager.getConnection(DB_URL, USER, PASS);

            // 执行更新操作
            String sql = "UPDATE your_table SET column_name = ? WHERE condition_column = ?";
            pstmt = conn.prepareStatement(sql);
            pstmt.setString(1, "new_value"); // 设置新的值
            pstmt.setString(2, "condition_value"); // 设置条件值

            int rowsUpdated = pstmt.executeUpdate();
            if (rowsUpdated > 0) {
                System.out.println("An existing user was updated successfully!");
            }
        } catch (SQLException se) {
            // 处理JDBC错误
            se.printStackTrace();
        } catch (Exception e) {
            // 处理Class.forName错误
            e.printStackTrace();
        } finally {
            // 关闭资源
            try {
                if (pstmt != null) pstmt.close();
            } catch (SQLException se2) {
            } // 什么都不做
            try {
                if (conn != null) conn.close();
            } catch (SQLException se) {
                se.printStackTrace();
            }
        }
    }
}