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 = "ACPOWER\":\"([\\d\\.]+)"; final String string = "{\"UPTIME\":\"00d 00:45:26\",\"RSSI\":96,\"VERSION\":\"1.10 04.05.2023 06:16\",\"DEVICENAME\":\"T2SG8BBF6C\",\"STATICIP\":\"192.168.88.68\",\"STATICGW\":\"192.168.88.1\",\"STATICSN\":\"255.255.255.0\",\"VGRID\":236.8,\"VBAT\":25.6,\"SETACPOWER\":700,\"TEMP\":42,\"DAC\":23637,\"CALSTEP\":0,\"MAXPOWER\":\"700\",\"POWERLIMIT\":700,\"VBATCUTOFF\":24,\"VBATREBOOT\":24.5,\"SUN2IP\":\"\",\"SUN3IP\":\"\",\"SUN2ROUNDTRIP\":\"0\",\"SUN2SETPOINT\":0,\"SUN2POWERLIMIT\":0,\"SUN3ROUNDTRIP\":\"0\",\"SUN3SETPOINT\":0,\"SUN3POWERLIMIT\":0,\"METERURL\":\"http://192.168.88.57/status\",\"METER_USER\":\"admin\",\"METER_PASS\":\"\",\"JSONKEYS\":\"total_power\",\"METERINTERVAL\":\"500\",\"METERREADOUT\":142,\"ZEPCTARGET\":\"15\",\"ZEPCAVERAGE\":\"20\",\"MQTT_SERVER\":\"\",\"MQTT_PORT\":\"1883\",\"MQTT_USER\":\"\",\"MQTT_PASS\":\"\",\"HADISCOVERY\":0,\"MQTT_ACSETPOINTOVR_NAME\":\"T2SG8BBF6C/ACSETPOINTOVR\",\"MQTT_ACSETPOINTOVR_VALUE\":\"\",\"MQTT_DACOVR_NAME\":\"T2SG8BBF6C/DACOVR\",\"MQTT_DACOVR_VALUE\":\"\",\"MQTT_CALSTEPOVR_NAME\":\"T2SG8BBF6C/CALSTEPOVR\",\"MQTT_CALSTEPOVR_VALUE\":\"\",\"MQTT_METEROVR_NAME\":\"T2SG8BBF6C/METEROVR\",\"MQTT_METEROVR_VALUE\":\"\",\"MQTT_MAXPOWEROVR_NAME\":\"T2SG8BBF6C/MAXPOWEROVR\",\"MQTT_MAXPOWEROVR_VALUE\":\"\",\"MQTT_TARGETOVR_NAME\":\"T2SG8BBF6C/TARGETOVR\",\"MQTT_TARGETOVR_VALUE\":\"\",\"MQTT_ACSETPOINT_NAME\":\"T2SG8BBF6C/ACSETPOINT\",\"MQTT_ACSETPOINT_VALUE\":7000,\"MQTT_ACDISPLAY_NAME\":\"T2SG8BBF6C/ACDISPLAY\",\"MQTT_ACDISPLAY_VALUE\":7211,\"MQTT_VGRID_NAME\":\"T2SG8BBF6C/VGRID\",\"MQTT_VGRID_VALUE\":2368,\"MQTT_VBAT_NAME\":\"T2SG8BBF6C/VBAT\",\"MQTT_VBAT_VALUE\":256,\"MQTT_DAC_NAME\":\"T2SG8BBF6C/DAC\",\"MQTT_DAC_VALUE\":23637,\"MQTT_CALSTEP_NAME\":\"T2SG8BBF6C/CALSTEP\",\"MQTT_CALSTEP_VALUE\":0,\"MQTT_TEMPERATURE_NAME\":\"T2SG8BBF6C/TEMPERATURE\",\"MQTT_TEMPERATURE_VALUE\":42,\"MQTT_METER_NAME\":\"T2SG8BBF6C/METER\",\"MQTT_METER_VALUE\":\"2963.35\",\"MQTT\":\"not set\",\"ACPOWER\":\"721.10 W\",\"ACPOWERSUN2\":\"not set\",\"ACPOWERSUN3\":\"not set\",\"METERPOWER\":\"2963.35 W\",\"ZEPCPOWER\":\"2083.90 W\"}"; 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