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 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]
  • 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

/
/
g

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 = "Data Transfer Element (\\d+):(Full|Empty)(?: \\(Storage Element (\\d+) Loaded\\):VolumeTag = (\\w+))?"; final String string = "Storage Changer /dev/sg2:2 Drives, 48 Slots ( 0 Import/Export )\n" + "Data Transfer Element 0:Full (Storage Element 2 Loaded):VolumeTag = ALF029L5 \n" + "Data Transfer Element 1:Empty\n" + " Storage Element 1:Full \n" + " Storage Element 2:Empty\n" + " Storage Element 3:Empty\n" + " Storage Element 4:Full \n" + " Storage Element 5:Full :VolumeTag=AEF812LV \n" + " Storage Element 6:Full :VolumeTag=ALF021L5 \n" + " Storage Element 7:Full :VolumeTag=ALF019L5 \n" + " Storage Element 8:Full \n" + " Storage Element 9:Full :VolumeTag=ALF035L5 \n" + " Storage Element 10:Full :VolumeTag=AEF839LV \n" + " Storage Element 11:Full :VolumeTag=ALF018L5 \n" + " Storage Element 12:Empty\n" + " Storage Element 13:Full :VolumeTag=AEF832LV \n" + " Storage Element 14:Full :VolumeTag=ALF002L5 \n" + " Storage Element 15:Full :VolumeTag=ALF020L5 \n" + " Storage Element 16:Full :VolumeTag=ALF016L5 \n" + " Storage Element 17:Full :VolumeTag=AEF831LV \n" + " Storage Element 18:Full \n" + " Storage Element 19:Full :VolumeTag=AEF814LV \n" + " Storage Element 20:Full :VolumeTag=ALF010L5 \n" + " Storage Element 21:Full :VolumeTag=ALF022L5 \n" + " Storage Element 22:Full :VolumeTag=ALF001L5 \n" + " Storage Element 23:Full :VolumeTag=AEF830LV \n" + " Storage Element 24:Full :VolumeTag=ALF008L5 \n" + " Storage Element 25:Full :VolumeTag=ALF038L5 \n" + " Storage Element 26:Full \n" + " Storage Element 27:Full :VolumeTag=ALF034L5 \n" + " Storage Element 28:Full :VolumeTag=ALF009L5 \n" + " Storage Element 29:Full :VolumeTag=AEF821LV \n" + " Storage Element 30:Full :VolumeTag=ALF013L5 \n" + " Storage Element 31:Full :VolumeTag=AEF822LV \n" + " Storage Element 32:Full :VolumeTag=ALF006L5 \n" + " Storage Element 33:Full :VolumeTag=ALF028L5 \n" + " Storage Element 34:Full :VolumeTag=AEF813LV \n" + " Storage Element 35:Full :VolumeTag=ALF007L5 \n" + " Storage Element 36:Full :VolumeTag=ALF012L5 \n" + " Storage Element 37:Full :VolumeTag=ALF005L5 \n" + " Storage Element 38:Full :VolumeTag=ALF027L5 \n" + " Storage Element 39:Full :VolumeTag=ALF025L5 \n" + " Storage Element 40:Full :VolumeTag=AEF823LV \n" + " Storage Element 41:Full :VolumeTag=ALF036L5 \n" + " Storage Element 42:Full :VolumeTag=ALF017L5 \n" + " Storage Element 43:Full :VolumeTag=AEF811LV \n" + " Storage Element 44:Full :VolumeTag=AEF810LV \n" + " Storage Element 45:Full :VolumeTag=ALF024L5 \n" + " Storage Element 46:Full :VolumeTag=ALF003L5 \n" + " Storage Element 47:Full :VolumeTag=ALF032L5 \n" + " Storage Element 48:Full :VolumeTag=ALF039L5 "; final Pattern pattern = Pattern.compile(regex); 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