Java 跨服务器将一个库的表数据同步到另一个库 demo

下面是一个简单的 Java demo，演示如何跨服务器将一个库的表数据同步到另一个库：

import java.sql.*;

public class DataSyncDemo {

    public static void main(String[] args) {

        // 源库连接信息
        String srcUrl = "jdbc:mysql://localhost:3306/src_db";
        String srcUser = "root";
        String srcPassword = "123456";

        // 目标库连接信息
        String destUrl = "jdbc:mysql://192.168.1.100:3306/dest_db";
        String destUser = "admin";
        String destPassword = "password";

        // 表名和字段名
        String tableName = "users";
        String[] columnNames = { "id", "name", "age" };

        Connection srcConn = null;
        Connection destConn = null;
        Statement srcStmt = null;
        PreparedStatement destStmt = null;
        ResultSet rs = null;

        try {
            // 连接源库
            srcConn = DriverManager.getConnection(srcUrl, srcUser, srcPassword);
            srcStmt = srcConn.createStatement();
            String sql = "SELECT * FROM " + tableName;
            rs = srcStmt.executeQuery(sql);

            // 连接目标库
            destConn = DriverManager.getConnection(destUrl, destUser, destPassword);
            destStmt = destConn.prepareStatement(
                "INSERT INTO " + tableName + " (" + String.join(",", columnNames) + ") VALUES (?, ?, ?)"
            );

            // 遍历源库结果集，插入到目标库
            while (rs.next()) {
                for (int i = 0; i < columnNames.length; i++) {
                    destStmt.setObject(i + 1, rs.getObject(columnNames[i]));
                }
                destStmt.addBatch();
            }
            destStmt.executeBatch();

            System.out.println("Data sync succeeded.");

        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            try {
                rs.close();
                srcStmt.close();
                destStmt.close();
                srcConn.close();
                destConn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}

这个 demo 连接了两个 MySQL 数据库，将源库中的 `users` 表同步到了目标库中。需要根据实际情况修改连接信息、表名和字段名等。