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

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 = "(?si)m_dwErrorCode\\s*=\\s*(?<code>\\dx\\d+);\\s*_stprintf\\(.*?\\(.*?\\((?<description>.*?)\\).*?;\\s*m_dwOutError\\s*=\\s*(?<error>[\\w_]+);\\s*m_OutSeverity\\s*=\\s*(?<severity>[\\w_]+)"; final String string = "m_dwErrorCode = 0; \n" + "m_dwOutError = HOP_OK; \n" + "m_OutSeverity = CCC_INFORMATION; \n" + "_stprintf(m_OutDevStr, _T(\"\"));\n" + "if (0x00000000 & value)\n" + "{\n" + " \n" + " m_dwErrorCode = 0x0;\n" + " /* Ready state. */\n" + " // m_StatusStr = \" Ready(eSTATUS_READY)\";\n" + "}\n" + "if (0x00000001 & value)\n" + "{\n" + " m_bProceeding = true;\n" + " /* proceed */\n" + " //m_StatusStr = \" Proceeding(eSTATUS)\";\n" + "}\n" + "if (0x00002000 & value)\n" + "{\n" + " m_bEmpty = true;\n" + " // We only want to check this error only at certain times.\n" + " if (m_bCheckEmpty)\n" + " {\n" + " if ((m_Attributes.dwMediaID == CUBE1) ||\n" + " (m_Attributes.dwMediaID == CUBE2) ||\n" + " /*(m_Attributes.dwMediaID == SCALLOPED) ||*/ // Added\n" + " (m_Attributes.dwMediaID == FOLDED))\n" + " {\n\n" + " m_dwErrorCode = 0x00002000;\n" + " _stprintf(m_OutDevStr, _T(\"0x1000 - %s(MP Tray Empty)\"), errorStr);\n" + " m_dwOutError = HOP_TRAY_EMPTY;\n" + " m_OutSeverity = CCC_INFORMATION;\n" + " }\n" + " }\n" + " //HOP_TRAY_EMPTY\n" + " ///* MSI empty. */\n" + " //m_bTrayEmpty = true;\n" + " //// m_StatusStr = \" MSI empty(eSTATUS_MSI_EMPTY)\";\n" + "}\n" + "if (0x00004000 & value)\n" + "{\n" + " /* empty. */\n" + " m_dwErrorCode = 0x4000;\n" + " _stprintf(m_OutDevStr, _T(\"0x4000 - %s(Tray 1 empty)\"), errorStr);\n" + " m_dwOutError = HOP_TRAY_01_EMPTY;\n" + " m_OutSeverity = CCC_INFORMATION;\n" + "}\n" + "if (0x00008000 & value)\n" + "{\n" + " /* Tray 2 empty. */\n" + " m_dwErrorCode = 0x8000;\n" + " _stprintf(m_OutDevStr, _T(\"0x8000 - %s(Tray 2 empty)\"), errorStr);\n" + " m_dwOutError = HOP_TRAY_02_EMPTY;\n" + " m_OutSeverity = CCC_INFORMATION;\n" + "}\n" + "if (0x00010000 & value)\n" + "{\n" + " /* Tray 3 empty. */\n" + " m_dwErrorCode = 0x10000;\n" + " _stprintf(m_OutDevStr, _T(\"0x10000 - %s(Tray 3 empty)\"), errorStr);\n" + " m_dwOutError = HOP_TRAY_03_EMPTY;\n" + " m_OutSeverity = CCC_INFORMATION;\n" + "}"; 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