java 时间处理

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;
import java.util.Calendar;
import java.util.Date;

/**
 * @description:
 * @projectName:({PROJECT_NAME}
 * @see:{PACKAGE_NAME}
 * @author:fb
 * @createTime:2021/12/1 10:58
 * @version:1.0
 */
public class Test2021120102 {
  public static void main(String[] args) throws ParseException {
    System.out.println("获取当前时间戳");
    System.out.println(System.currentTimeMillis());
    System.out.println("时间戳格式化");
    System.out.println(
        new SimpleDateFormat("yyyy-MM-dd '----' HH:mm:ss z")
            .format(new Date(System.currentTimeMillis())));
    System.out.println(
        new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z").format(new Date(System.currentTimeMillis())));
    System.out.println(
        new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date(System.currentTimeMillis())));
    System.out.println("java.util.Date 获取时间");
    System.out.println(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date()));
    System.out.println("Calendar 获取时间");
    System.out.println(
        new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")
            .format(new Date(Calendar.getInstance().getTimeInMillis())));
    System.out.println(
        new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(Calendar.getInstance().getTime()));

    System.out.println("LoalDate 获取日期，没有时间");

    System.out.println(DateTimeFormatter.ofPattern("yyyy-MM-dd").format(LocalDate.now()));

    System.out.println("LoalTime 获取时间，没有日期");
    System.out.println(DateTimeFormatter.ofPattern("HH:mm:ss").format(LocalTime.now()));

    System.out.println("LoalDateTime 获取时间，没有日期");
    System.out.println(
        DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss").format(LocalDateTime.now()));
  }
}