What are the regular expressions commonly used in java

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1. Numeric validation expression

Demand expression number ^ [0-9] * the number of $n bit ^\ d {n} $mmurn bit ^\ d {m N} $zero and non-zero beginning numbers ^ (^ ([1-9] [0-9] *) + (. [0-9] {1m 2})? $positive or negative numbers with 1-2 decimal places ^ (\ -)?\ d + (\.\ d {1pc2})? $positive, negative, And decimal ^ (\-|\ +)?\ d+ (\.\ d+)? $positive real number ^ [0-9] + (. [0-9] {2}) with two decimal places? $positive real number ^ [0-9] + (. [0-9] {1 ^ 3})? $non-zero positive integer ^ [1-9]\ dcounting $or ^ ([1-9] [0-9] *) {1pm 3} $or ^\ +? [1-9] [0-9] * $non-zero negative integer ^\-[1-9] [] 0-9 "* $or ^-[1-9]\ dcircle $non-negative integer ^\ DX $or ^ [1-9]\ d* | 0$ non-positive integer ^-[1-9]\ d* | 0$ or ^ (-\ d+) | (0 +) $non-negative floating point number ^\ d+ (\.\ d+)? $or ^ [1-9]\ d*\ .\ d* | 0\.\ d* [1-9]\ d* | 0?\ .0 + | 0$ non-positive floating point ^ ((-\ d+ (\.\ d+)?) | (0 + (\ .0 +)?)) $or ^ (([1-9]\ d*\.\ d* | 0.\ d* [1-9]\ d*)) | 0?\ .0 + | 0$ positive floating point ^ [1-9]\ d*.\ d* | 0.\ d* [1-9]. 9] [0-9] $or ^ (([0-9] +. [0-9] * [1-9] [0-9] *) | ([0-9] * [1-9] [0-9] +) | ([0-9] * [1-9] [0-9] *)) $negative floating point ^-([1-9]\ d*\.\ d* | 0.\ d* [1-9]\ d* ) $or ^ (- ([0-9] +\. [0-9] * [1-9] [0-9] *) | ([0-9] * [1-9] [0-9] *) | ([0-9] * [1-9] [0-9] *) $floating point number ^ (-?\ d +) (\.\ d +)? $or ^ -? ([1-9]\ d *\.\ d * | 0\.\ d * [1-9]\ d* | 0?\ .0 + | 0) at least n bits ^\ d {n } $

2. Character validation expression

Demand expression Chinese character ^ [\ u4e00 -\ u9fa5] {0 } $English and numbers ^ [A-Za-z0-9] + $or ^ [A-Za-z0-9] {4pm 40} $all characters 3-20 in length ^. {3pm 20} $string of 26 letters ^ [A-Za-z] + $string of 26 uppercase letters ^ [Amurz] + $string of 26 lowercase letters ^ [A-Za-z] + $consisting of numbers and The 26-letter string ^ [A-Za-z0-9] + $consists of numbers, A string consisting of 26 English letters or underscores ^\ w {3 u9FA5A-Za-z0 20} $Chinese, English, numbers including underscores ^ [\ u4E00 -\ u9FA5A-Za-z0-9] + $, English, numbers but excluding symbols such as underscores ^ [\ u4E00 -\ u9FA5A-Za-z0-9] + $or ^ [\ u4E00 -\ u9FA5A-Za-z0-9] {2} 20} $can be entered with ^% &' Characters such as =? $\ "[^% &',; =? $\ x22] + prohibit the input of characters containing ~ [^ ~\ x22] +. * match any Chinese characters except\ n / [\ u4E00 -\ u9FA5] /

3. Special requirements expression

Requirement expression Email address ^\ w+ ([- +.]\ w+) * @\ w+ ([-.]\ w+) *\.\ w+ ([-.]\ w+) * $domain name [a-zA-Z0-9] [- a-zA-Z0-9] {0a-zA-Z0 62} (/. [a-zA-Z0-9] [- a-zA-Z0-9] {0jue 62}) + /.? InternetURL [a-zA-z] +: / / [^\ s] * Or ^ http://([\w-]+\.)+[\w-]+(/[\w-./?%&=]*)?$ Mobile phone number ^ (13 [0-9] | 14 [5 | 7] | 15 [0 | 1 | 2 | 3 | 5 | 6 | 7 | 8 | 9] | 18 [0 | 1 | 2 | 5 | 6 | 7 | 8 | 9])\ d {8} $phone number ("XXX-XXXXXXX", "XXXX-XXXXXXXX", "XXX-XXXXXXX", "XXX-XXXXXXXX", "XXXXXXX" and "XXXXXXXX) ^ (\ (\ d {3, 4} -) |\ d {3. 4} -)?\ d {7} $domestic telephone number (0511-4405222, 021-87888822)\ d {3} -\ d {8} |\ d {4} -\ d {7} ID card number (15 digits, 18 digits) ^\ d {15} |\ d {18} $short ID card number (number, number, 18 digits) End of letter x) ^ ([0-9]) {7Magne18} (x | X)? $or ^\ d {8pr 18} | [0-9x] {8pr 18} | [0-9X] {8p 18}? is the account legal (beginning with the letter)? Allow 5-16 bytes, alphanumeric underscore) ^ [a-zA-Z] [a-zA-Z0-9 _] {4jue 15} $

Password (starts with a letter, is between 6 and 18 in length and can only contain letters, numbers and underscores) ^ [a-zA-Z]\ w {5pc17} $strong password (must contain a combination of uppercase and lowercase letters and numbers, no special characters can be used The length is between 8 and 10) ^ (? =. *\ d) (? =. * [Amurz]) (? =. * [Amurz]). {8pm 10} $date format ^\ d {4} -\ d {1J 2} -\ d {1J 2} 12 months of a year (01x 09 and 1x 12) ^ (0? [1-9] | 1 [0-2]) 31 days of a month (01pm 09 and 1x 31) ^ (0? [ 1-9]) | (1 | 2) [0-9]) | 30 | 31) expressions of $"10000.00" and "10000.00" And expressions of "10000" and "10000" ^ [1-9] [0-9] * $without "points" Any number that does not start with 0, however, this also means that a character "0" does not pass the expression of ^ (0 | [1-9] [0-9] *) $, a 0 or a number that does not start with 0. We can also allow a negative sign ^ (0 | -? [1-9] [0-9] *) $0 or a number that may be negative and begins with a non-zero. Let the user start with 0. Remove the minus sign, too. What we want to add next is the possible decimal part ^ [0-9] + (. [0-9] +)? $it must be stated that there should be at least 1 digit after the decimal point, so "10." No, but "10" and "10.2" are passed by ^ [0-9] + (. [0-9] {2})? there must be two places ^ [0-9] + (. [0-9] {1)) after the $decimal point? $allows the user to write only one decimal place. Comma ^ [0-9] {1pc3} (, [0-9] {3}) * (. [0-9] {1pc2})? $1 to 3 digits, followed by any comma + 3 digits, comma becomes optional rather than necessary ^ ([0-9] + | [0-9] {1 + 3}) [0-9] {3}) *) (. [0-9] {1 u9fa5 2})? $xml file ^ ([a-zA-Z] + -?) + [a-zA-Z0-9] +\. [X | X] [m | M] [l | L] $Chinese characters [\ u4e00 -\ u9fa5] double-byte characters [^\ x00 -\ xff] (including Chinese characters) Can be used to calculate the length of a string (a double-byte character length meter)) blank lines\ n\ s *\ r (can be used to delete blank lines) HTML tag] * >. *? | (incomplete Need to find separately) the leading and trailing blank characters ^\ s* |\ sblank $or (^\ s*) | (\ sblank $) (can be used to delete white space characters at the beginning and end of a line (including spaces, tabs, page feeds, etc.) Very useful expression) Tencent QQ number [1-9] [0-9] {4 } (Tencent QQ number starts from 10000) China Postal Code [1-9]\ d {5} (?!\ d) (China Postal Code is 6 digits) IP address\ d +\.\ d + (useful when extracting IP address) IP address ((?): (?) 25 [0-5] | 2 [0-4]\ d | [01]?\ d?\ d)\\.) {3} ( ?: 25 [0-5] | 2 [0-4]\ d | [01]?\\ d?\\ d) IP-v4 address\\ b (?: 25 [0-5] | 2 [0-4] [0-9] | [01]? [0-9] [0-9]?)\\.) {3} (?: 25 [0-5] | 2 [0-4] [0-9] | [01]? [0-9] [0-9]) ?)\\ b (useful when extracting IP addresses) verify IP-v6 addresses

(([0-9a-fA-F] {1rect 4}:) {79a-fA-F 7} [0-9a-fA-F] {1pr 4} | ([0-9a-fA-F] {1pr 4}:) {1Mague 7}: | ([0-9a-fA-F] {1pr 4}:) {1pr 6}: [0-9a-fA-F] {1pr 4} | ([0-9a-fA-F] {1pm 4}:) {1pm 5} (: [0-9a-fA-F] {1pm 4}) {1pm 2}) | | ([0-9a-fA-F] {1score4}:) {19a-fA-F 4} (: [0-9a-fA-F] {1score4}) {19a-fA-F 3} | ([0-9a-fA-F] {1Power4}:) {19a-fA-F 3} (: [0-9a-fA-F] {1pr 4}) {1c4} | ([0-9a-fA-F] {1pr 4}:) {1pr 2} (: [0-9a-fA-F] {1pm 4}) {1pm 5} | ] {19a-fA-F 4}: (: [0-9a-fA-F] {1 9a-fA-F 4}) {1 9a-zA-Z 6}) | (: (: [0-9a-fA-F] {1 9a-zA-Z 4}) {1 9a-fA-F 7} |:) | (: [0-9a-fA-F] {0pr 4}) {0pr 4}% [0 -] {1 | |:: (ffff (: 0 {0 9a-fA-F 4}) {0Power1}:) {0ffff 1} ((25 [0-5]) | (2 [0-4] | 1 {0Power1} [0-9]) {0Magne1} [0-9]) {0Magne1} (25 [0-5] | (2 [0-4] | 1 {0quotient 1} [0-9]) {0jin1} [0-9]) | ([0-0] 1}:) {1pm 4}: (25) [0-5] | (2 [0-4] | 1 {0rect 1} [0-9]) {0rect 1} [0-9])\\.) {3jue 3} (25 [0-5] | (2 [0-4] | 1 {0jue 1} [0-9]))

Subnet mask ((?: 25 [0-5] | 2 [0-4]\ d | [01]?\\ d?\\ d)\\.) {3} (?: 25 [0-5] | 2 [0-4]\ d | [01]?\ d?\\ d)) check date

^ (?: (! 0000) [0-9] {4}-(: 0 [1-9] | 1 [0-2])-(?: 0 [1-9] | 1 [0-9] | 2 [0-8]) | (?: 0 [13-9] | 1 [0-2])-(?: 29 | 30) | (?: 0 [13578] | 1 [02])-31) | (?: [0-9] {2} (?: 0 [48]) | 2468] [048] | [13579] [26]) | (?: 0 [48] | [2468] [048] | [13579] [26]) 00)-02-

Format date check, has considered flat leap year $(date check in "yyyy-mm-dd" format, has considered flat leap year.) Extract comments to find CSS attributes ^\\ s * [a-zA-Z\\ -] +\\ s * [:] {1}\\ s [a-zA-Z0-9\\ s.#] + [;] {1} extract page hyperlinks

(] *) (href= "https?:\ /\ /) ((?! (: (?: (?: www\\.)?'. Implode ('| (?: www\\.), $follow_list).)) [^" rel= "external nofollow"] +) "((?. *\\ brel=) [^ >] *) (?: [^ >] *) >

Extract web page images\\

] * [src] * = * [\ "\] {0Magne1} ([^\"\] *) extract the web page color code ^ # ([A-Fa-f0-9] {6} | [A-Fa-f0-9] {3}) $file extension validation ^ ([a-zA-Z]\: |\)\\ ([^\] +\) * [^\\] \ /: *? "|] +\ .txt (l)? $judge the IE version ^. * MSIE [5-8] (?:\. [0-9] +)? (?!. * Trident\ / [5-9]\ .0). * $full-width symbol / [\ uFF00-\ uFFFF] / half-width symbol / [\ u0000 -\ u00FF] / above is all the content of the article" what are java regular expressions? " Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!