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

/
/

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)Rx Power[\\s\\t]+\\(mW\\)\\|[\\s\\t]+(.*?)[\\s\\t]+\\|.*?\\|.*?\\|[\\s\\t]+HIGH[\\s\\t]+(.*?)[\\s\\t]+\\|[\\s\\t]+(.*?)[\\s\\t]+\\|.*?\\|.*?\\|.*?\\|.*?\\|.*?\\|[\\s\\t]+LOW[\\s\\t]+(.*?)[\\s\\t]+\\|[\\s\\t]+(-?\\d+)[\\s\\t]+\\|"; final String string = "+--------------------- XCVR DIAGNOSTICS - Port 9 -----------------+\n" + "| | | Alarm | Warning |\n" + "| Output | Value | Threshold | Flag | Threshold | Flag |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Temp (degC)| 27.961 | HIGH 83.000 | 0 | HIGH 80.000 | 0 |\n" + "| | | LOW -13.000 | 0 | LOW -10.000 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Tx Bias (mA)| 35.002 | HIGH 80.000 | 0 | HIGH 75.000 | 0 |\n" + "| | | LOW 15.000 | 0 | LOW 20.000 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Tx Power (mW)| 0.59930 | HIGH 1.41250 | 0 | HIGH 1.25890 | 0 |\n" + "| | | LOW 0.19950 | 0 | LOW 0.25120 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Tx Power (dBm)| -2.2236 | HIGH +1.4999 | 0 | HIGH +0.9999 | 0 |\n" + "| | | LOW -7.0006 | 0 | LOW -5.9998 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Rx Power (mW)| 0.57770 | HIGH 1.77830 | 0 | HIGH 1.58490 | 0 |\n" + "| | | LOW 0.01000 | 0 | LOW 0.01580 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Rx Power (dBm)| -2.3830 | HIGH +2.5001 | 0 | HIGH +2.0000 | 0 |\n" + "| | | LOW -20.0000 | 0 | LOW -18.0134 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Aux1 | 3.32770 | HIGH 3.63000 | 0 | HIGH 3.50000 | 0 |\n" + "| | | LOW 3.00000 | 0 | LOW 3.10000 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Aux2 | 0.00000 | HIGH 5.50000 | 0 | HIGH 5.30000 | 0 |\n" + "| | | LOW 4.50000 | 0 | LOW 4.70000 | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| 1.8V | | HIGH | 0 | HIGH | 0 |\n" + "| | | LOW | 0 | LOW | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| -5.2V | | HIGH | 0 | HIGH | 0 |\n" + "| | | LOW | 0 | LOW | 0 |\n" + "+---------------+----------+---------------+------+---------------+------+\n" + "| Fault/Status Flags |\n" + "+--------+-------+--------+--------+--------+--------+--------+----------+\n" + "| TX_NR | TX | TX_CDR | RX_NR | | RX_CDR | | Reset |\n" + "| Status | Fault | Unlock | Status | RX_LOS | Unlock | MOD_NR | Complete |\n" + "+--------+-------+--------+--------+--------+--------+--------+----------+\n" + "| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |\n" + "+--------+-------+--------+--------+--------+--------+--------+----------+\n" + "|APD Sply| TEC | Wavelength | Bad Ch | New Ch | UnSupp | |\n" + "| Fault | Fault | Unlocked | Req | Acq | TxDith | |\n" + "+--------+-------+-----------------+--------+--------+--------+----------+\n" + "| 0 | 0 | 0 | 0 | 0 | 0 | |\n" + "+--------+-------+-----------------+--------+--------+--------+----------+\n" + "| General Control/Status Signals |\n" + "+---------+---------+--------+--------+--------+-------+-----+-----------+\n" + "| TX | Soft TX | | P_Down | Soft | | RX | Data_Not |\n" + "| Disable | Disable | MOD_NR | State | P_Down | INTRn | LOS | _Ready |\n" + "+---------+---------+--------+--------+--------+-------+-----+-----------+\n" + "| 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 |\n" + "+---------+---------+--------+--------+--------+-------+-----+-----------+\n" + "| TX_NR | TX | TX_CDR | RX_NR | RX_CDR | Tx | Tx | |\n" + "| State | Fault | Unlock | State | Unlock | Tune | Dith | |\n" + "+---------+---------+--------+--------+--------+-------+-----+-----------+\n" + "| 0 | 0 | 0 | 0 | 0 | 0 | 0 | |\n" + "+---------+---------+--------+--------+--------+-------+-----+-----------+\n" + "| Module Capabilites |\n" + "+-------------------------+-----------------------+----------------------+\n" + "| Laser First Freq (GHz) | Laser Last Freq (GHz) | Grid Spacing (GHz) |\n" + "+-------------------------+-----------------------+----------------------+\n" + "| 0 | 0 | 0 |\n" + "+-------------------------+-----------------------+----------------------+\n" + "| Frequency Channel Control |\n" + "+---------------------------------+--------------------------------------+\n" + "| Channel Number Set | Frequency Error (GHz) |\n" + "+---------------------------------+--------------------------------------+\n" + "| 0 | 0 |\n" + "+---------------------------------+--------------------------------------+"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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