将String转化为Long，并将Long转化为Date

package org.ljh.test.javaee;

import java.text.SimpleDateFormat;
import java.util.Date;

public class StringToLongToDate {

	public static String parseTime(String s){

		//将字符串转化为Long类型
		Long timeLong = Long.parseLong(s);
		//将Long类型转化为Date
		Date date = new Date(timeLong);

		//将Date类型格式化
		SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		String dateString = sdf.format(date);
		return dateString;

	}

	public static void main(String[] args){
		System.out.println(parseTime("5223456789236"));
	}

}

输出结果：2135-07-12 00:13:09