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java 如何从字符串里面提取时间

如何从字符串里面提取时间

今天接到一个需求,需要从一段带有时间串的字符串里面提取出时间保存。

"PDFS(iZh9k5gurgwcwpZ) 2020-01-01 21:27:36.560 >订单编号:1112233 提交订单成功! 跟踪号:待取跟踪号 内部单号:2342244"

需要从上面数据中心提取出 2020-01-01 21:27:36要怎么操作呢?

我们可以使用正则表达式

对时间串进行提取,并处理,代码如下:

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package com.epean.trade.framework.util;

import org.apache测试数据mons.lang.time.DateFormatUtils;

import org.apache测试数据mons.lang.time.DateUtils;

import java.text.ParseException;

import java.util.Date;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

/**

  * Created by chpeng on 2020/08/18 0008.

  */

public class StringDateUtils {

     /**

      *

      * @Description: 从字符串中截取出正确的时间

      * @param stringTime

      * @return:

      * @throws

      */

     public static Date cutDate(String stringTime) {

         String regs[] = { "\\d{4}年\\d{2}月\\d{2}日\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{2}时\\d{2}分" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}时\\d{2}分" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{1}时\\d{2}分" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}时\\d{2}分" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\d{2}时\\d{2}分" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{2}时" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{1}时" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}时" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{1}时" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\d{2}时" , "\\d{4}年\\d{2}月\\d{2}日" ,

                 "\\d{4}年\\d{2}月\\d{1}日" , "\\d{4}年\\d{1}月\\d{2}日" ,

                 "\\d{4}年\\d{1}月\\d{1}日" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{2}:\\d{1}:\\d{2}" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}:\\d{1}:\\d{2}" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{2}:\\d{2}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{1}:\\d{2}" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}:\\d{2}" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{1}:\\d{2}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\d{2}:\\d{2}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{2}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\s\\d{1}" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{2}" ,

                 "\\d{4}年\\d{1}月\\d{2}日\\s\\d{1}" ,

                 "\\d{4}年\\d{2}月\\d{2}日\\d{2}" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{2}" , "\\d{4}-\\d{2}-\\d{2}" ,

                 "\\d{4}-\\d{2}-\\d{1}" , "\\d{4}-\\d{1}-\\d{2}" ,

                 "\\d{4}-\\d{1}-\\d{1}" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}-\\d{1}-\\d{1}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{2}时" ,

                 "\\d{4}-\\d{2}-\\d{2}\\s\\d{1}时" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{2}时" ,

                 "\\d{4}-\\d{1}-\\d{2}\\s\\d{1}时" , "\\d{4}.\\d{2}.\\d{2}" ,

                 "\\d{4}.\\d{2}.\\d{1}" , "\\d{4}.\\d{1}.\\d{2}" ,

                 "\\d{4}.\\d{1}.\\d{1}" ,

                 "\\d{4}.\\d{2}.\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}.\\d{2}.\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{4}.\\d{1}.\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}.\\d{1}.\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{4}.\\d{1}.\\d{1}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{4}.\\d{2}.\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{4}.\\d{2}.\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{4}.\\d{1}.\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{4}.\\d{1}.\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{4}.\\d{2}.\\d{2}\\s\\d{2}" ,

                 "\\d{4}.\\d{2}.\\d{2}\\s\\d{1}" ,

                 "\\d{4}.\\d{1}.\\d{2}\\s\\d{2}" ,

                 "\\d{4}.\\d{1}.\\d{2}\\s\\d{1}" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{2}时" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{1}时" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{2}时" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{1}时" ,

                 "\\d{4}/\\d{2}/\\d{2}" ,

                 "\\d{4}/\\d{2}/\\d{1}" ,

                 "\\d{4}/\\d{1}/\\d{2}" ,

                 "\\d{4}/\\d{1}/\\d{1}" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{2}" ,

                 "\\d{4}/\\d{2}/\\d{2}\\s\\d{1}" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{2}" ,

                 "\\d{4}/\\d{1}/\\d{2}\\s\\d{1}" ,

                 "\\d{2}月\\d{2}日\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{2}月\\d{2}日\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{1}月\\d{2}日\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{2}月\\d{2}日\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{2}月\\d{2}日\\s\\d{2}时\\d{2}分" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}时\\d{2}分" ,

                 "\\d{1}月\\d{2}日\\s\\d{1}时\\d{2}分" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}时\\d{2}分" ,

                 "\\d{2}月\\d{2}日\\d{2}时\\d{2}分" ,

                 "\\d{2}月\\d{2}日\\s\\d{2}时" ,

                 "\\d{2}月\\d{2}日\\s\\d{1}时" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}时" ,

                 "\\d{1}月\\d{2}日\\s\\d{1}时" ,

                 "\\d{2}月\\d{2}日\\d{2}时" , "\\d{4}年\\d{2}月\\d{2}日" ,

                 "\\d{2}月\\d{1}日" , "\\d{4}年\\d{1}月\\d{2}日" ,

                 "\\d{1}月\\d{1}日" ,

                 "\\d{2}月\\d{2}日\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{2}月\\d{2}日\\s\\d{2}:\\d{1}:\\d{2}" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}:\\d{1}:\\d{2}" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{2}月\\d{2}日\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{2}月\\d{2}日\\s\\d{2}:\\d{2}" ,

                 "\\d{2}月\\d{2}日\\s\\d{1}:\\d{2}" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}:\\d{2}" ,

                 "\\d{1}月\\d{2}日\\s\\d{1}:\\d{2}" ,

                 "\\d{2}月\\d{2}日\\d{2}:\\d{2}" ,

                 "\\d{2}月\\d{2}日\\s\\d{2}" ,

                 "\\d{2}月\\d{2}日\\s\\d{1}" ,

                 "\\d{1}月\\d{2}日\\s\\d{2}" ,

                 "\\d{1}月\\d{2}日\\s\\d{1}" ,

                 "\\d{2}月\\d{2}日\\d{2}" ,

                 "\\d{2}-\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{2}-\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{1}-\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{1}-\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{2}-\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{2}-\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{2}-\\d{2}\\s\\d{2}" , "\\d{4}-\\d{2}-\\d{2}" ,

                 "\\d{2}-\\d{1}" , "\\d{4}-\\d{1}-\\d{2}" ,

                 "\\d{1}-\\d{1}" ,

                 "\\d{2}-\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{2}-\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{1}-\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{1}-\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{1}-\\d{1}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{2}-\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{2}-\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{1}-\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{1}-\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{2}-\\d{2}\\s\\d{2}时" ,

                 "\\d{2}-\\d{2}\\s\\d{1}时" ,

                 "\\d{1}-\\d{2}\\s\\d{2}时" ,

                 "\\d{1}-\\d{2}\\s\\d{1}时" , "\\d{4}.\\d{2}.\\d{2}" ,

                 "\\d{2}.\\d{1}" , "\\d{4}.\\d{1}.\\d{2}" ,

                 "\\d{1}.\\d{1}" ,

                 "\\d{2}.\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{2}.\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{1}.\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{1}.\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{1}.\\d{1}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{2}.\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{2}.\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{1}.\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{1}.\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{2}.\\d{2}\\s\\d{2}" ,

                 "\\d{2}.\\d{2}\\s\\d{1}" ,

                 "\\d{1}.\\d{2}\\s\\d{2}" ,

                 "\\d{1}.\\d{2}\\s\\d{1}" ,

                 "\\d{2}/\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{2}/\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{1}/\\d{2}\\s\\d{2}时\\d{2}分\\d{2}秒" ,

                 "\\d{1}/\\d{2}\\s\\d{1}时\\d{2}分\\d{2}秒" ,

                 "\\d{2}/\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{2}/\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{1}/\\d{2}\\s\\d{2}时\\d{2}分" ,

                 "\\d{1}/\\d{2}\\s\\d{1}时\\d{2}分" ,

                 "\\d{2}/\\d{2}\\s\\d{2}时" ,

                 "\\d{2}/\\d{2}\\s\\d{1}时" ,

                 "\\d{1}/\\d{2}\\s\\d{2}时" ,

                 "\\d{1}/\\d{2}\\s\\d{1}时" ,

                 "\\d{2}/\\d{2}" ,

                 "\\d{2}/\\d{1}" ,

                 "\\d{1}/\\d{2}" ,

                 "\\d{1}/\\d{1}" ,

                 "\\d{2}/\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{2}/\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{1}/\\d{2}\\s\\d{2}:\\d{2}:\\d{2}" ,

                 "\\d{1}/\\d{2}\\s\\d{1}:\\d{2}:\\d{2}" ,

                 "\\d{2}/\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{2}/\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{1}/\\d{2}\\s\\d{2}:\\d{2}" ,

                 "\\d{1}/\\d{2}\\s\\d{1}:\\d{2}" ,

                 "\\d{2}/\\d{2}\\s\\d{2}" ,

                 "\\d{2}/\\d{2}\\s\\d{1}" ,

                 "\\d{1}/\\d{2}\\s\\d{2}" ,

                 "\\d{1}/\\d{2}\\s\\d{1}" ,

         };

         String str = "" ;

         Date date = null ;

         for (String reg : regs) {

             String temp = match(reg, stringTime);

             if (temp.length() > str.length()) {

                 str = temp;

                 if (! "" .equals(str)) {

                     date = formatDate(str);

                 }

             }

         }

         return date;

     }

     /**

      *

      * @Description: 把String格式的时间转化为date

      * @param stringTime

      * @return:

      * @throws

      */

     public static Date formatDate(String stringTime) {

         Date date = null ;

         if (StringUtils.isNotBlank(stringTime)) {

             String[] pattern = new String[] { "yyyy年MM月dd日HH时mm分ss秒" ,

                     "yyyy年MM月dd日 HH时mm分ss秒" , "yyyy年MM月dd日HH时mm分" ,

                     "yyyy年MM月dd日 HH时mm分" , "yyyy年MM月dd日 HH时" , "yyyy年MM月dd日HH时" ,

                     "yyyy年MM月dd日" , "yyyy年MM月dd日HH:mm:ss" ,

                     "yyyy年MM月dd日 HH:mm:ss" , "yyyy年MM月dd日HH:mm" ,

                     "yyyy年MM月dd日 HH:mm" , "yyyy年MM月dd日 HH" , "yyyy年MM月dd日HH" ,

                     "yyyy-MM-dd HH时mm分ss秒" , "yyyy-MM-dd HH时mm分" ,

                     "yyyy-MM-dd HH时" , "yyyy-MM-dd" , "yyyy-MM-dd HH:mm:ss" ,

                     "yyyy-MM-dd HH:mm" , "yyyy-MM-dd HH" ,

                     "yyyy/MM/dd HH时mm分ss秒" , "yyyy/MM/dd HH时mm分" ,

                     "yyyy/MM/dd HH时" , "yyyy/MM/dd" , "yyyy/MM/dd HH:mm:ss" ,

                     "yyyy/MM/dd HH:mm" , "yyyy/MM/dd HH" , "yyyy.MM.dd HH:mm:ss" ,

                     "yyyy.MM.dd HH:mm" , "yyyy.MM.dd HH" , "yyyy.MM.dd" ,

                     "yyyyMMdd" , };

             try {

                 date = DateUtils.parseDate(stringTime, pattern);

             } catch (ParseException e) {

                 e.printStackTrace();

             }

         }

         return date;

     }

     public static String match(String reg, String stringTime) {

         Pattern p = Pattern测试数据pile(reg);

         Matcher m = p.matcher(stringTime);

         String s = "" ;

         if (m.find()) {

             s += m.group();

         }

         return s;

     }

     /**

      * 格式化

      * @Title: DateToString

      * @Description:

      * @param time

      * @return:

      * @throws

      */

     public static String DateToString(Date time) {

         String newDate = DateFormatUtils.format(time, "yyyy-MM-dd HH:mm:ss" );

         return newDate;

     }

    

     public static void main(String[] args) {

         String stringTime = "PDFS(iZh9k5gurgwcwpZ) 2020-01-01 21:27:36.560 >订单编号:1112233   提交订单成功!   跟踪号:待取跟踪号   内部单号:2342244" ;

         Date date = cutDate(stringTime);

         System.out.println(date);

         System.out.println(DateToString(date));

     }

}

我们测试一下:

没问题的。

从字符串中提取年份,要求输出1000-4999之间的所有年份

正则表达式

常用正则表达式:

\d : 数字字符匹配。等效于 [0-9] \D : 非数字字符匹配。等效于 [^0-9]。 {n} : n为非负整数,正好匹配n次 {n,} : n为非负整数,至少匹配n次 [a-z] : 字符范围。匹配指定范围内的任何字符,例如,"[a-z]"匹配"a"到"z"范围内的任何小写字母。 [^a-z] : 反向范围字符。匹配不在指定的范围内的任何字符。例如,"[^a-z]"匹配任何不在"a"到"z"范围内的任何字符。 \ : 将下一字符标记为特殊字符、文本、反向引用或八进制转义符 ^ : 匹配输入字符串开始的位置 $ : 匹配输入字符串结尾的位置。 * : 零次或多次匹配前面的字符或子表达式。例如,zo* 匹配"z"和"zoo"。* 等效于 {0,} + : 一次或多次匹配前面的字符或子表达式。例如,"zo+"与"zo"和"zoo"匹配,但与"z"不匹配。+ 等效于 {1,}。 ? : 零次或一次匹配前面的字符或子表达式。例如,"do(es)?"匹配"do"或"does"中的"do"。? 等效于 {0,1}。

?

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import java.util.*;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

public class JingDong {

     public static void main(String[] args) {

         Scanner sc = new Scanner(System.in);

         String str = sc.nextLine();

         String reg = "\\D[1-4]\\d{3}\\D" ; //eg:a2019a、a2019、2019a

       // 前面不能是数字,后面也不能是数字

         str = str + "a" ;

         str = "a" + str;

         Pattern p = Pattern测试数据pile(reg);

         Matcher matcher = p.matcher(str);

        while (matcher.find()){

             System.out.print(matcher.group( 0 ).substring( 1 , 5 ) + " " );

         }

     }

     public static boolean isNum( char a){

         if (Character.isDigit(a)){

             return true ;

         } else

             return false ;

     }

}

传统匹配:

?

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import java.util.*;

public class JingDong {

     public static void main(String[] args) {

         Scanner sc = new Scanner(System.in);

           String str = sc.nextLine();

         if (str.length()<= 2000 ){

             String out = "" ;

             for ( int i = 0 ; i < str.length()- 1 ;) {

                 if (isNum(str.charAt(i) )&& Integer.parseInt(String.valueOf(str.charAt(i))) <= 4 && Integer.parseInt(String.valueOf(str.charAt(i)))>= 1 ){

                     if (isNum(str.charAt(i+ 1 ))){

                         if (isNum(str.charAt(i+ 2 ))){

                             if (isNum(str.charAt(i+ 3 ))){

                                 if (!isNum(str.charAt(i+ 4 ))){

                                     out += str.substring(i,i+ 4 );

                                     out += " " ;

                                     i+= 4 ;

                                 }

                                 i+= 4 ;

                             } else

                             i++;

                         } else

                          i++;

                     } else

                         i++;

                 } else

                     i++;

             }

             System.out.println(out);

         }

     public static boolean isNum( char a){

         if (Character.isDigit(a)){

             return true ;

         } else

             return false ;

     }

}

以上为个人经验,希望能给大家一个参考,也希望大家多多支持。

原文链接:https://blog.csdn.net/flycp/article/details/108141694

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