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 = "(?s-i)(<User>\\s*USER_NAME\\s*<\\/User>.*?<Password>\\s*)(\\S+)(\\s*<\\/Password>)"; final String string = " <Connection type=\"Teradata\" autoCommit=\"True\">\n" + " <Path>Teradata\\BEDW - USER_NAME1</Path>\n" + " <AutoConnect>False</AutoConnect>\n" + " <DefaultOnStartup>False</DefaultOnStartup>\n" + " <Database>\n" + " </Database>\n" + " <Host>teraprd2.ca.host.com</Host>\n" + " <User>USER_NAME1</User>\n" + " <Category>F00000FF:Production</Category>\n" + " <Password>ENCRYPTED_PWD1</Password>\n" + " <WinAuth>False</WinAuth>\n" + " <LastConnectionDate>2019-09-11T16:32:09.1945969</LastConnectionDate>\n" + " <SessionMode>Teradata</SessionMode>\n" + " <SessionCharacterSet>UTF16</SessionCharacterSet>\n" + " <PortNumber>1025</PortNumber>\n" + " <DataEncryption>False</DataEncryption>\n" + " <ResponseBufferSize>1040000</ResponseBufferSize>\n" + " </Connection>\n" + " </Connections>\n" + " <Groups />\n" + "</Group>\n" + "<Group name=\"EFBI - USER_NAME\" description=\"\">\n" + " <Path>Teradata</Path>\n" + " <Connections>\n" + " <Connection type=\"Teradata\" autoCommit=\"True\">\n" + " <Name>USER_NAME @TERADEVL (EFBI_DEV1_USAGE_METRICS_B)</Name>\n" + " <Path>Teradata\\EFBI - USER_NAME</Path>\n" + " <AutoConnect>False</AutoConnect>\n" + " <DefaultOnStartup>False</DefaultOnStartup>\n" + " <Database>EFBI_DEV1_USAGE_METRICS_B</Database>\n" + " <Host>teradevl.ca.host.com</Host>\n" + " <User>USER_NAME</User>\n" + " <Category>BCCF87FF:Development</Category>\n" + " <Password>ENCRYPTED_PWD2</Password>\n" + " <WinAuth>False</WinAuth>\n" + " <LastConnectionDate>2019-04-30T15:41:31.3601044</LastConnectionDate>\n" + " <SessionMode>Teradata</SessionMode>\n" + " <SessionCharacterSet>UTF16</SessionCharacterSet>\n" + " <PortNumber>1025</PortNumber>\n" + " <DataEncryption>False</DataEncryption>\n" + " <DefaultDatabase>EFBI_DEV1_USAGE_METRICS_B</DefaultDatabase>\n" + " <ResponseBufferSize>1040000</ResponseBufferSize>\n" + " </Connection>\n"; final String subst = "$1(NEW_ENCRYPTED_PWD)$3"; 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