long long类型转Qtime

将long long类型转换为QTime需要先将long long类型转换为QDateTime，然后再使用QDateTime的time()方法获取QTime类型。示例代码如下：

long long timestamp = 1626769081000; // 示例long long类型时间戳
QDateTime datetime = QDateTime::fromMSecsSinceEpoch(timestamp); // 将long long类型转换为QDateTime类型
QTime time = datetime.time(); // 获取QDateTime类型的时间

其中，fromMSecsSinceEpoch()方法可以将long long类型的时间戳转换为QDateTime类型。如果需要将当前时间转换为QTime类型，则可以使用QTime的currentTime()方法获取当前时间。示例代码如下：

QTime time = QTime::currentTime(); // 获取当前时间

相关问题

linux下用getopt_long实现ls命令的代码

可以参考以下代码：

#include <stdio.h>
#include <getopt.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <sys/stat.h>
#include <string.h>

#define MAX_PATH 1024

static struct option long_options[] = {
    {"all", no_argument, NULL, 'a'},
    {"list", no_argument, NULL, 'l'},
    {"help", no_argument, NULL, 'h'},
    {NULL, 0, NULL, 0}
};

int main(int argc, char** argv) {
    int opt;
    int all_flag = 0, list_flag = 0;
    char path[MAX_PATH] = ".";

    while ((opt = getopt_long(argc, argv, "alh", long_options, NULL)) != -1) {
        switch (opt) {
        case 'a':
            all_flag = 1;
            break;
        case 'l':
            list_flag = 1;
            break;
        case 'h':
            printf("Usage: ls [OPTION] [DIRECTORY]\n");
            printf("List information about the FILEs (the current directory by default).\n\n");
            printf("Options:\n");
            printf("  -a, --all            do not ignore entries starting with .\n");
            printf("  -l, --list           use a long listing format\n");
            printf("  -h, --help           display this help and exit\n");
            exit(0);
        default:
            break;
        }
    }

    if (argc > optind) {
        strncpy(path, argv[optind], MAX_PATH);
    }

    DIR* dirp = opendir(path);
    if (dirp == NULL) {
        printf("Cannot open directory: %s\n", path);
        exit(1);
    }

    struct dirent *dp;
    while ((dp = readdir(dirp)) != NULL) {
        if (all_flag == 0 && dp->d_name[0] == '.') {
            continue;
        }

        char full_path[MAX_PATH];
        snprintf(full_path, sizeof(full_path), "%s/%s", path, dp->d_name);

        struct stat st;
        if (lstat(full_path, &st) == -1) {
            perror("lstat");
            continue;
        }

        if (list_flag == 1) {
            char buf[100];
            strftime(buf, sizeof(buf), "%b %d %H:%M", localtime(&st.st_mtime));
            printf("%c%s %ld %s %s %ld %s %s\n",
                   S_ISDIR(st.st_mode) ? 'd' : '-',
                   st.st_mode & S_IRUSR ? "r" : "-",
                   st.st_mode & S_IWUSR ? "w" : "-",
                   st.st_mode & S_IXUSR ? "x" : "-",
                   st.st_mode & S_IRGRP ? "r" : "-",
                   st.st_mode & S_IWGRP ? "w" : "-",
                   st.st_mode & S_IXGRP ? "x" : "-",
                   st.st_mode & S_IROTH ? "r" : "-",
                   st.st_mode & S_IWOTH ? "w" : "-",
                   st.st_mode & S_IXOTH ? "x" : "-",
                   st.st_nlink, getpwuid(st.st_uid)->pw_name,
                   getgrgid(st.st_gid)->gr_name,
                   st.st_size, buf, dp->d_name);
        } else {
            printf("%s  ", dp->d_name);
        }
    }

    closedir(dirp);
    printf("\n");
    return 0;
}

希望对你有所帮助！

用JAVA写一个定时任务，定时清理es mtime 30天之前的数据 采用 delete_by_query

可以使用 Quartz 定时任务框架来实现，以下是一个简单的示例代码：

首先引入相关依赖：

<dependency>
  <groupId>org.quartz-scheduler</groupId>
  <artifactId>quartz</artifactId>
  <version>2.3.2</version>
</dependency>
<dependency>
  <groupId>org.elasticsearch.client</groupId>
  <artifactId>elasticsearch-rest-high-level-client</artifactId>
  <version>7.0.0</version>
</dependency>

然后定义一个 Job 类来执行清理操作：

import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.deletebyquery.DeleteByQueryRequest;
import org.elasticsearch.action.deletebyquery.DeleteByQueryResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.quartz.Job;
import org.quartz.JobExecutionContext;
import org.quartz.JobExecutionException;

import java.io.IOException;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.util.Date;

public class EsCleanJob implements Job {
    private RestHighLevelClient esClient;

    public EsCleanJob(RestHighLevelClient esClient) {
        this.esClient = esClient;
    }

    @Override
    public void execute(JobExecutionContext context) throws JobExecutionException {
        System.out.println("开始清理es数据...");
        // 计算30天前的时间戳
        LocalDateTime thirtyDaysAgo = LocalDateTime.now().minusDays(30);
        long timestamp = thirtyDaysAgo.toInstant(ZoneOffset.of("+8")).toEpochMilli();
        // 构建 delete by query 请求
        DeleteByQueryRequest request = new DeleteByQueryRequest("index_name");
        request.setQuery(QueryBuilders.rangeQuery("mtime").lt(timestamp));
        // 执行 delete by query 操作
        try {
            DeleteByQueryResponse response = esClient.deleteByQuery(request, RequestOptions.DEFAULT);
            System.out.println("清理完成，删除 " + response.getDeleted() + " 条数据");
        } catch (IOException e) {
            throw new JobExecutionException("清理es数据失败", e);
        }
    }
}

最后在主函数中启动定时任务：

import org.elasticsearch.client.RestHighLevelClient;
import org.quartz.*;
import org.quartz.impl.StdSchedulerFactory;

public class EsCleanScheduler {
    public static void main(String[] args) throws SchedulerException {
        // 创建 es 客户端
        RestHighLevelClient esClient = new RestHighLevelClient(/* es 配置 */);
        // 创建 JobDetail 实例
        JobDetail jobDetail = JobBuilder.newJob(EsCleanJob.class).withIdentity("esCleanJob").build();
        // 创建 Trigger 实例
        Trigger trigger = TriggerBuilder.newTrigger()
                .withIdentity("esCleanTrigger")
                .withSchedule(SimpleScheduleBuilder.repeatSecondlyForever(86400)) // 每隔一天执行一次
                .build();
        // 创建 Scheduler 实例
        SchedulerFactory schedulerFactory = new StdSchedulerFactory();
        Scheduler scheduler = schedulerFactory.getScheduler();
        scheduler.start();
        scheduler.scheduleJob(jobDetail, trigger);
    }
}

这样就完成了定时清理 es 数据的任务。