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 = "devSummaryJson=\\{.*(?=\\}]\\})"; final String string = "{\"expand\": \"names,schema\",\"startAt\": 0,\"maxResults\": 50,\"total\": 1,\"issues\": [{\"expand\": \"operations,versionedRepresentations,editmeta,changelog,renderedFields\",\"id\": \"641955\",\"self\": \"https://rb-tracker.bosch.com/tracker19/rest/api/latest/issue/641955\",\"key\": \"EDATOOL-1411\",\"fields\": {\"created\": \"2022-12-06T11:14:36.000+0100\",\"customfield_10000\": \"{summaryBean=com.atlassian.jira.plugin.devstatus.rest.SummaryBean@24a1688f[summary={pullrequest=com.atlassian.jira.plugin.devstatus.rest.SummaryItemBean@23f2f23c[overall=PullRequestOverallBean{stateCount=0, state='OPEN', details=PullRequestOverallDetails{openCount=0, mergedCount=0, declinedCount=0}},byInstanceType={}], build=com.atlassian.jira.plugin.devstatus.rest.SummaryItemBean@321de5ab[overall=com.atlassian.jira.plugin.devstatus.summary.beans.BuildOverallBean@6ca82c6[failedBuildCount=0,successfulBuildCount=0,unknownBuildCount=0,count=0,lastUpdated=<null>,lastUpdatedTimestamp=<null>],byInstanceType={}], review=com.atlassian.jira.plugin.devstatus.rest.SummaryItemBean@5fc3e1e6[overall=com.atlassian.jira.plugin.devstatus.summary.beans.ReviewsOverallBean@7a2d42e3[stateCount=0,state=<null>,dueDate=<null>,overDue=false,count=0,lastUpdated=<null>,lastUpdatedTimestamp=<null>],byInstanceType={}], deployment-environment=com.atlassian.jira.plugin.devstatus.rest.SummaryItemBean@2740d0b0[overall=com.atlassian.jira.plugin.devstatus.summary.beans.DeploymentOverallBean@75ceaa2c[topEnvironments=[],showProjects=false,successfulCount=0,count=0,lastUpdated=<null>,lastUpdatedTimestamp=<null>],byInstanceType={}], repository=com.atlassian.jira.plugin.devstatus.rest.SummaryItemBean@35c2a9a2[overall=com.atlassian.jira.plugin.devstatus.summary.beans.CommitOverallBean@2568cfa3[count=0,lastUpdated=<null>,lastUpdatedTimestamp=<null>],byInstanceType={}], branch=com.atlassian.jira.plugin.devstatus.rest.SummaryItemBean@40c4eee[overall=com.atlassian.jira.plugin.devstatus.summary.beans.BranchOverallBean@4131b89[count=0,lastUpdated=<null>,lastUpdatedTimestamp=<null>],byInstanceType={}]},errors=[],configErrors=[]], devSummaryJson={\\\"cachedValue\\\":{\\\"errors\\\":[],\\\"configErrors\\\":[],\\\"summary\\\":{\\\"pullrequest\\\":{\\\"overall\\\":{\\\"count\\\":0,\\\"lastUpdated\\\":null,\\\"stateCount\\\":0,\\\"state\\\":\\\"OPEN\\\",\\\"details\\\":{\\\"openCount\\\":0,\\\"mergedCount\\\":0,\\\"declinedCount\\\":0,\\\"total\\\":0},\\\"open\\\":true},\\\"byInstanceType\\\":{}},\\\"build\\\":{\\\"overall\\\":{\\\"count\\\":0,\\\"lastUpdated\\\":null,\\\"failedBuildCount\\\":0,\\\"successfulBuildCount\\\":0,\\\"unknownBuildCount\\\":0},\\\"byInstanceType\\\":{}},\\\"review\\\":{\\\"overall\\\":{\\\"count\\\":0,\\\"lastUpdated\\\":null,\\\"stateCount\\\":0,\\\"state\\\":null,\\\"dueDate\\\":null,\\\"overDue\\\":false,\\\"completed\\\":false},\\\"byInstanceType\\\":{}},\\\"deployment-environment\\\":{\\\"overall\\\":{\\\"count\\\":0,\\\"lastUpdated\\\":null,\\\"topEnvironments\\\":[],\\\"showProjects\\\":false,\\\"successfulCount\\\":0},\\\"byInstanceType\\\":{}},\\\"repository\\\":{\\\"overall\\\":{\\\"count\\\":0,\\\"lastUpdated\\\":null},\\\"byInstanceType\\\":{}},\\\"branch\\\":{\\\"overall\\\":{\\\"count\\\":0,\\\"lastUpdated\\\":null},\\\"byInstanceType\\\":{}}}},\\\"isStale\\\":true}}\"}}]}"; 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