Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A single character of: a, b, c or d
    [[ab][cd]]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Character class intersection
    [\w&&[^\d]]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

"
"
gmiu

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "([\\p{InHiragana}+|\\p{InKatakana}+|\\p{IsHan}+]+[県都府道])(.*)"; final String string = "〒100-0001 北海道千代田区千代田1−1−1\n" + "青森県\n" + "岩手県\n" + "宮城県\n" + "秋田県\n" + "山形県\n" + "福島県\n" + "茨城県\n" + "栃木県\n" + "群馬県\n" + "埼玉県\n" + "千葉県\n" + "東京都\n" + "神奈川県\n" + "新潟県\n" + "富山県\n" + "石川県\n" + "福井県\n" + "山梨県\n" + "長野県\n" + "岐阜県\n" + "静岡県\n" + "愛知県\n" + "三重県\n" + "滋賀県\n" + "京都府\n" + "大阪府\n" + "兵庫県\n" + "奈良県\n" + "和歌山県\n" + "鳥取県\n" + "島根県\n" + "岡山県\n" + "広島県\n" + "山口県\n" + "徳島県\n" + "香川県\n" + "愛媛県\n" + "高知県\n" + "福岡県\n" + "佐賀県\n" + "長崎県\n" + "熊本県\n" + "大分県\n" + "宮崎県\n" + "鹿児島県\n" + "沖縄県"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html