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

r"
"
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 = "(?:ALARM[\\s]*)(?:\\d*)[A-Za-z\\s\\d\\.=]*(?:Alarm\\sraised\\stime)\\s+=\\s+([\\d\\-]+\\s[\\d\\:]+)\\s+(?:Location\\sinfo)\\s+=\\s+Local\\sCell\\sID=([\\d]+)(?:,\\s[a-zA-Z]+\\s[A-Z]+\\s[A-Z]+\\s[a-zA-Z\\=,]+\\s[a-zA-Z\\=-]+\\s[a-zA-Z\\=-]+\\s[a-zA-Z\\=-_,]+)[\\s\\,A-Za-z0-9=\\_]*(?:eNodeB\\sID=)([0-9]+)(?:,.+\\s\\s+.+\\s+)(?:Cleared\\stype)\\s+=\\s+([a-zA-Z ]+)(?:[\\sA-Za-z\\s=]*)([\\d-]*\\s[\\d:]+)"; final String string = "L_SAMBIL\n" + "+++ L_SAMBIL 2020-09-21 11:53:53\n" + "O&M #1502\n" + "%%/*1882154167*/LST ALMLOG:ALMTP=all,CLRFLG=cleared-1&uncleared-1,CLRSD=2020&09&21,CLRED=2020&09&22,STARTAID=29240,ENDAID=29240;%%\n" + "RETCODE = 0 Operation succeeded\n\n" + "ALARM 72712 Fault Major eNodeB 29240 Signaling \n" + " Sync serial No. = 162656\n" + " Alarm name = Cell Unavailable\n" + " Alarm raised time = 2020-09-21 06:36:19\n" + " Location info = Local Cell ID=2, Cell FDD TDD indication=FDD, NB-IoT Cell Flag=FALSE, Cell Name=L_SAMBIL2, eNodeB ID=15080, Cell ID=2, Specific Problem=External link fault\n" + " Function = eNodeB Function Name=L_SAMBIL, objId=0\n" + " Cleared type = Normally cleared\n" + " Cleared time = 2020-09-21 06:39:42\n" + " Special info = RAT_INFO=L, AFFECTED_RAT=L, DID=NULL\n" + " Special info1 = AF_L=L_SAMBIL\n\n" + "ALARM 72713 Fault Major eNodeB 29240 Signaling \n" + " Sync serial No. = 162655\n" + " Alarm name = Cell Unavailable\n" + " Alarm raised time = 2020-09-21 06:36:19\n" + " Location info = Local Cell ID=3, Cell FDD TDD indication=FDD, NB-IoT Cell Flag=FALSE, Cell Name=L_SAMBIL3, eNodeB ID=15080, Cell ID=3, Specific Problem=External link fault\n" + " Function = eNodeB Function Name=L_SAMBIL, objId=0\n" + " Cleared type = Normally cleared\n" + " Cleared time = 2020-09-21 06:39:41\n" + " Special info = RAT_INFO=L, AFFECTED_RAT=L, DID=NULL\n" + " Special info1 = AF_L=L_SAMBIL\n\n" + "ALARM 72711 Fault Major eNodeB 29240 Signaling \n" + " Sync serial No. = 162654\n" + " Alarm name = Cell Unavailable\n" + " Alarm raised time = 2020-09-21 06:36:19\n" + " Location info = Local Cell ID=1, Cell FDD TDD indication=FDD, NB-IoT Cell Flag=FALSE, Cell Name=L_SAMBIL1, eNodeB ID=15080, Cell ID=1, Specific Problem=External link fault\n" + " Function = eNodeB Function Name=L_SAMBIL, objId=0\n" + " Cleared type = Normally cleared\n" + " Cleared time = 2020-09-21 06:39:41\n" + " Special info = RAT_INFO=L, AFFECTED_RAT=L, DID=NULL\n" + " Special info1 = AF_L=L_SAMBIL\n" + "(Number of results = 3)\n\n" + "--- END"; 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