MyBatis 实现动态排序的多表查询

public class OrderByPageUtils {


    /**
     * 将驼峰命名法转换为下划线命名法
     *
     * @param camelCaseString 驼峰命名的字符串
     * @return 下划线命名的字符串
     */
    public static String convertCamelToSnake(String camelCaseString) {
        StringBuilder result = new StringBuilder();
        for (char ch : camelCaseString.toCharArray()) {
            if (Character.isUpperCase(ch)) {
                result.append('_').append(Character.toLowerCase(ch));
            } else {
                result.append(ch);
            }
        }
        return result.toString();
    }

    /**
     * 根据前端传递的字段、排序方向和表别名生成排序 SQL 片段
     *
     * @param sortField     排序字段
     * @param sortDirection 排序方向 ("asc" 或 "desc")
     * @param tableAlias    表别名
     * @return 排序 SQL 片段
     */
    public static String getSortSql(String sortField, String sortDirection, String tableAlias) {
        if (sortField == null || sortDirection == null) {
            return "";
        }

        // 将驼峰命名法转换为下划线命名法
        String snakeCaseField = convertCamelToSnake(sortField);

        // 过滤排序字段，确保只有字母、数字和下划线
        String sanitizedSortField = snakeCaseField.replaceAll("[^a-zA-Z0-9_]", "");
        String sanitizedSortDirection = "asc".equalsIgnoreCase(sortDirection) ? "ASC" : "DESC";

        if (sanitizedSortField.isEmpty()) {
            return "";
        }

        // 加上表别名
        if (tableAlias != null && !tableAlias.isEmpty()) {
            sanitizedSortField = tableAlias + "." + sanitizedSortField;
        }

        return " ORDER BY " + sanitizedSortField + " " + sanitizedSortDirection;
    }
}

List<xxxxVO> selectTableList(@Param("sql") String sql);

<select id = "selectTableList" resultType="xxx.VO">
	select a.id,b.name from data as a
	inner join user as b on a.user_id = b.user_id
	<if test = "sql != null and sql != ''">
		${sql}
    </if>
</select>

// ... 业务处理
String sql = OrderByPageUtils.getSortSql(orderField.getSortField(), orderField.getSortDirection(), "a");

// dao
mapper.selectTableList(sql);