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

Substitution

Processing...

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 = "^.*added:[\\s\\S]*?(?=^[^+-])"; final String string = "demo, demo-setga, Deployment (apps) has changed:\n" + "...\n" + "- image: \"imagedemo43\"\n" + "+ image: \"imagedemo44\"\n" + "...\n" + "demo, demo-app1, Deployment (apps) has been removed:\n" + "- # Source: /charts/app1/templates/deploy.yaml\n" + "- apiVersion: apps/v1\n" + "- imagePullSecrets:\n" + "- - name: demo-registry\n" + "+\n" + "demo, demo-app2, Deployment (apps) has changed:\n" + "...\n" + "- value: 4.2.0\n" + "+ value: 4.3.0\n" + "...\n" + "demo, demo-app4, Deployment (apps) has been added:\n" + "-\n" + "+ apiVersion: apps/v1\n" + "+ kind: Deployment\n" + "+ metadata:\n" + "+ heritage: Helm\n" + "+ imagePullSecrets:\n" + "+ - name: demo-registry\n" + "demo, demo-app9, Deployment (apps) has changed:\n" + "...\n" + "- value: 2.2.0\n" + "+ value: 4.3.0\n" + "...\n" + "demo, demo-app5, PodDisruptionBudget (policy) has been added:\n" + "-\n" + "+ apiVersion: policy/v1beta1\n" + "+ kind: PodDisruptionBudget\n" + "+ metadata:\n" + "+ app: app5\n" + "+ release: demo\n" + "../helm_var/test/dev/secrets.yaml.dec\n" + "demo, demo-app8, PodDisruptionBudget (policy) has been added:\n" + "-\n" + "+ # Source: test/charts/app5/templates/pdb.yaml\n" + "+ apiVersion: policy/v1beta1\n" + "+ matchLabels:\n" + "+ app: app5\n" + "+ release: demo\n" + "demo, demo-app9, Deployment (apps) has changed:\n" + "...\n" + "- value: 4.1.0\n" + "+ value: 9.3.0\n" + "..."; final String subst = ""; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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