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 = "<RawData>55014B467FFF0C10BEFF00+<\\/RawData>\\n\\n<PrimaryValue>(\\d+.\\d+)"; final String string = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n\n" + "-<Devices-Detail-Response xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns=\"http://www.embeddeddatasystems.com/schema/owserver\">\n\n" + "<PollCount>71</PollCount>\n\n" + "<DevicesConnected>2</DevicesConnected>\n\n" + "<LoopTime>2.048</LoopTime>\n\n" + "<DevicesConnectedChannel1>2</DevicesConnectedChannel1>\n\n" + "<DevicesConnectedChannel2>0</DevicesConnectedChannel2>\n\n" + "<DevicesConnectedChannel3>0</DevicesConnectedChannel3>\n\n" + "<DataErrorsChannel1>0</DataErrorsChannel1>\n\n" + "<DataErrorsChannel2>0</DataErrorsChannel2>\n\n" + "<DataErrorsChannel3>0</DataErrorsChannel3>\n\n" + "<VoltageChannel1>4.81</VoltageChannel1>\n\n" + "<VoltageChannel2>4.81</VoltageChannel2>\n\n" + "<VoltageChannel3>4.80</VoltageChannel3>\n\n" + "<VoltagePower>5.05</VoltagePower>\n\n" + "<DeviceName>OWServer_v2-Enet</DeviceName>\n\n" + "<HostName>EDSOWSERVER2</HostName>\n\n" + "<MACAddress>00:04:A3:BE:A9:F2</MACAddress>\n\n" + "<DateTime>2017-03-10 23:18:40</DateTime>\n\n\n" + "-<owd_DS18B20 Description=\"Programmable resolution thermometer\">\n\n" + "<Name>DS18B20</Name>\n\n" + "<Family>28</Family>\n\n" + "<ROMId>690516B3FC14FF28</ROMId>\n\n" + "<Health>7</Health>\n\n" + "<Channel>1</Channel>\n\n" + "<RawData>54014B467FFF0C10FDFF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000</RawData>\n\n" + "<PrimaryValue>21.2500 Deg C</PrimaryValue>\n\n" + "<Temperature Units=\"Centigrade\">21.2500</Temperature>\n\n" + "<UserByte1 Writable=\"True\">75</UserByte1>\n\n" + "<UserByte2 Writable=\"True\">70</UserByte2>\n\n" + "<Resolution>12</Resolution>\n\n" + "<PowerSource>255</PowerSource>\n\n" + "</owd_DS18B20>\n\n\n" + "-<owd_DS18B20 Description=\"Programmable resolution thermometer\">\n\n" + "<Name>DS18B20</Name>\n\n" + "<Family>28</Family>\n\n" + "<ROMId>020316B4A6C3FF28</ROMId>\n\n" + "<Health>7</Health>\n\n" + "<Channel>1</Channel>\n\n" + "<RawData>55014B467FFF0C10BEFF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000</RawData>\n\n" + "<PrimaryValue>21.3125 Deg C</PrimaryValue>\n\n" + "<Temperature Units=\"Centigrade\">21.3125</Temperature>\n\n" + "<UserByte1 Writable=\"True\">75</UserByte1>\n\n" + "<UserByte2 Writable=\"True\">70</UserByte2>\n\n" + "<Resolution>12</Resolution>\n\n" + "<PowerSource>255</PowerSource>\n\n" + "</owd_DS18B20>\n\n" + "</Devices-Detail-Response>"; 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