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

/
/
gm

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 = "\\s+([\\d]+[*]*[\\.]*[\\d]*[\\.]*[\\d]*)"; final String string = "PORO -- Generated : Petrel\n" + "-- Property name in Petrel : PHIT_Object Cutoff60\n" + " 28*0.00 0.03 0.03 9502*0.00 0.01 0.01 9502*0.00 0.01 0.01 9502*0.00 0.02 0.02 9502*0.00 0.02 0.01 9502*0.00 0.03 0.02 0.00 0.00\n" + " 9500*0.00 0.02 0.03 9502*0.00 0.03 0.02 9502*0.00 0.03 0.03 9502*0.00 0.01 0.01 9502*0.00 0.01 0.01 0.02 9501*0.00 0.01 0.01 0.01\n" + " 9501*0.00 0.02 0.03 0.02 9501*0.00 0.01 0.01 0.01 9501*0.00 0.02 0.02 0.02 9501*0.00 0.02 0.02 0.02 9501*0.00 0.01 0.02 0.02 0.00\n" + " 9500*0.00 0.01 0.02 0.02 9501*0.00 0.01 0.01 0.01 9501*0.00 0.02 0.02 0.02 9501*0.00 0.03 0.02 0.02 5*0.00 0.03 0.03 0.00 0.00\n" + " 9492*0.00 0.04 0.04 0.04 5*0.00 0.03 0.01 9494*0.00 0.01 0.02 0.02 5*0.00 0.02 0.02 9494*0.00 0.01 0.02 0.01 0.00 0.00 0.00 0.00\n" + " 0.00 0.01 0.02 0.02 9493*0.00 0.01 0.01 0.01 5*0.00 0.01 0.01 0.01 9493*0.00 0.03 0.04 0.02 0.02 0.00 0.00 0.00 0.00 0.02 0.03\n" + " 0.03 9493*0.00 0.01 0.01 0.01 0.01 0.00 0.00 5*0.01 9499*0.00 5*0.02 9493*0.00 0.03 0.03 0.03 0.04 0.00 0.00 0.03 0.02 0.02 0.02\n" + " 0.02 9493*0.00 0.03 0.02 0.01 0.01 0.00 6*0.01 9493*0.00 0.01 0.01 0.01 0.02 0.00 0.01 0.01 0.01 0.01 0.02 0.02 0.00 0.00 0.00\n" + " 9490*0.00 0.03 0.03 0.02 0.02 0.00 0.01 0.02 0.01 0.02 0.01 0.02 9494*0.00 0.03 0.01 0.01 0.00 0.01 0.01 0.01 0.01 0.02 0.02 0.00\n" + " 9492*0.00 0.03 0.03 0.02 0.02 0.02 0.01 0.01 0.02 0.02 0.01 0.03 9493*0.00 0.02 0.02 0.02 8*0.01 9493*0.00 0.03 0.03 0.02 0.02\n" + " 0.01 0.01 0.02 0.02 0.02 0.02 0.03 9493*0.00 5*0.02 0.01 0.01 0.01 0.01 0.02 0.03 9494*0.00 0.03 0.01 0.02 0.03 0.02 0.02 0.03\n" + " 0.02 0.02 0.03 0.02 9496*0.00 0.01 0.01 0.01 0.01 0.00 0.00 0.02 0.03 9496*0.00 0.02 0.01 0.02 0.01 0.03 0.03 0.03 0.01 0.00 0.00\n" + " 9495*0.00 0.01 0.00 0.01 0.01 0.01 0.02 0.01 0.01 9500*0.00 0.01 0.01 9495*0.00 0.02 0.03 0.01 0.01 0.02 0.01 0.02 0.02 0.03 0.03\n" + " 0.03 421*0.00 0.03 53*0.00 0.06 2560*0.00 0.06 53*0.00 0.05 6402*0.00 0.02 0.02 0.03 0.02 0.03 0.02 0.02 0.03 0.03 0.03 0.03 0.00\n" + " 420*0.00 0.06 53*0.00 0.07 2560*0.00 0.06 53*0.00 0.04 6402*0.00 0.03 0.04 0.03 5*0.02 0.03 0.03 0.03 421*0.00 0.07 0.00 0.00 0.00\n" + " 50*0.00 0.07 2560*0.00 0.06 53*0.00 0.05 6402*0.00 0.02 0.02 0.03 0.02 0.02 0.01 0.02 0.02 0.03 0.03 0.03 421*0.00 0.05 0.00 0.00\n" + " 51*0.00 0.06 2560*0.00 0.07 6456*0.00 0.01 0.04 0.03 0.01 0.02 0.00 0.00 0.02 0.02 0.02 0.01 421*0.00 0.06 0.00 0.00 0.00 0.00\n" + " 49*0.00 0.07 2560*0.00 0.08 53*0.00 0.07 53*0.00 0.06 6348*0.00 0.03 0.03 0.03 0.00 0.00 0.00 0.00 0.02 0.02 0.02 0.01 0.00 0.00\n" + " 419*0.00 0.06 53*0.00 0.07 2560*0.00 0.08 53*0.00 0.07 6402*0.00 0.04 0.04 0.04 5*0.00 0.03 0.03 0.03 421*0.00 0.05 0.00 0.00 0.00\n" + " 50*0.00 0.06 2506*0.00 0.06 53*0.00 0.05 53*0.00 0.06 6402*0.00 0.01 8*0.00 0.03 476*0.00 0.06 2506*0.00 0.07 0.00 0.00 0.00 0.00\n" + " 49*0.00 0.06 53*0.00 0.05 53*0.00 0.04 6508*0.00 0.01 108*0.00 0.02 162*0.00 0.05 53*0.00 0.06 2506*0.00 0.06 0.00 0.00 0.00 0.00\n" + " 49*0.00 0.05 53*0.00 0.06 9395*0.00 0.08 6509*0.00 9*0.01 45*0.00 0.01 106*0.00 0.01 108*0.00 0.02 162*0.00 0.04 0.00 0.00 0.00\n" + " 50*0.00 0.05 53*0.00 0.02 1712*0.00 0.02 7248*0.00 0.02 0.01 0.02 0.02 0.01 0.03 0.03 0.03 46*0.00 0.04 0.01 0.00 0.00 0.00 0.00\n" + " 0.00 0.00 0.02 99*0.00 0.01 108*0.00 0.01 77*0.00 0.03 53*0.00 0.04 30*0.00 0.05 53*0.00 0.06 53*0.00 0.03 0.00 0.00 0.00 0.00\n" + " 157*0.00 0.04 1550*0.00 0.03 102*0.00 0.03 636*0.00 0.07 53*0.00 0.08 6454*0.00 0.01 0.01 0.01 0.01 0.00 0.00 0.00 0.01 0.01 0.01\n" + " 44*0.00 0.01 0.01 6*0.00 0.01 0.01 98*0.00 0.01 108*0.00 0.01 77*0.00 0.01 53*0.00 0.02 30*0.00 0.04 53*0.00 0.04 0.00 0.00 0.00\n" + " 50*0.00 0.02 161*0.00 0.04 1550*0.00 0.05 102*0.00 0.05 636*0.00 0.07 53*0.00 0.07 53*0.00 0.06 6400*0.00 0.02 0.02 0.01 0.02 0.00\n" + " 0.00 0.00 0.00 0.01 45*0.00 0.03 0.01 6*0.00 0.01 0.01 0.02 0.02 96*0.00 0.01 108*0.00 0.03 162*0.00 0.03 53*0.00 0.04 0.00 0.00\n" + " 51*0.00 0.02 107*0.00 0.02 53*0.00 0.05 1550*0.00 0.02 102*0.00 0.03 636*0.00 0.10 2754*0.00 0.02 3753*0.00 0.01 0.01 0.01 0.02\n" + " 0.02 0.01 0.00 0.00 0.01 45*0.00 0.02 0.01 6*0.00 0.01 99*0.00 0.01 108*0.00 0.02 162*0.00 0.05 53*0.00 0.07 0.00 0.00 0.00 0.00\n" + " 49*0.00 0.04 107*0.00 0.04 53*0.00 0.07 1550*0.00 0.02 102*0.00 0.04 0.03 635*0.00 0.08 53*0.00 0.07 53*0.00 0.06 0.00 0.00 0.00\n" + " 50*0.00 0.05 269*0.00 0.05 53*0.00 0.05 2268*0.00 0.03 53*0.00 0.03 3699*0.00 0.03 0.03 0.02 0.02 0.02 0.02 0.03 0.02 0.00 0.00\n" + " 44*0.00 0.03 0.02 106*0.00 0.01 108*0.00 0.02 162*0.00 0.05 53*0.00 0.06 53*0.00 0.05 107*0.00 0.03 53*0.00 0.05 0.00 0.00 0.00\n" + " 1650*0.00 0.04 636*0.00 0.07 53*0.00 0.08 53*0.00 0.05 53*0.00 0.04 323*0.00 0.04 6022*0.00 0.02 0.02 0.01 0.02 0.02 0.02 0.02\n" + " 0.02 0.02 0.01 0.03 43*0.00 0.03 0.02 0.00 0.01 0.01 0.00 0.00 0.00 0.02 0.01 0.02 0.02 96*0.00 0.01 108*0.00 0.03 0.00 0.00 0.00\n" + " 128*0.00 0.02 30*0.00 0.07 53*0.00 0.05 53*0.00 0.04 107*0.00 0.04 53*0.00 0.06 1653*0.00 0.03 690*0.00 0.06 0.00 0.00 0.00 0.00\n" + " 49*0.00 0.04 53*0.00 0.05 269*0.00 0.04 53*0.00 0.04 2268*0.00 0.02 53*0.00 0.02 539*0.00 0.02 53*0.00 0.03 0.03 0.00 0.00 0.00\n" + " 49*0.00 0.05 0.04 52*0.00 0.04 0.04 52*0.00 0.04 701*0.00 0.03 53*0.00 0.03 2187*0.00 0.01 0.01 0.02 0.02 0.02 0.02 0.00 0.01 0.00\n" + " 0.01 0.03 43*0.00 0.03 0.01 0.00 0.01 0.01 0.00 0.00 0.00 0.00 0.01 0.02 0.03 96*0.00 0.01 108*0.00 0.04 131*0.00 0.02 0.00 0.00\n" + " 28*0.00 0.04 53*0.00 0.05 53*0.00 0.03 107*0.00 0.02 53*0.00 0.05 5045*0.00 0.02 593*0.00 0.02 53*0.00 0.01 0.01 0.00 0.00 0.00\n" + " 49*0.00 0.02 0.02 52*0.00 0.01 0.02 52*0.00 0.01 2943*0.00 0.04 0.04 0.00 0.03 0.02 0.02 0.00 0.02 0.00 0.02 0.00 0.00 0.00 0.00\n" + " 40*0.00 0.05 0.03 0.00 0.02 0.02 0.00 0.00 0.00 0.00 0.02 0.03 97*0.00 0.02 108*0.00 0.03 162*0.00 0.05 53*0.00 0.07 0.00 0.00\n" + " 51*0.00 0.05 107*0.00 0.04 53*0.00 0.06 5639*0.00 0.03 54*0.00 0.02 53*0.00 0.03 52*0.00 0.03 0.03 52*0.00 0.02 0.00 0.00 0.00 /"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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