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 = "([\\w_]+)\\t([\\w_]+)\\t([\\w_]+)"; final String string = "albatross_v7 g_coeffExit ExtBandsExitCoeff\n" + "albatross_v7 g_dayFilter ExtDayNotToTrade\n" + "albatross_v7 g_period ExtBandsPeriod\n" + "albatross_v7 g_tradeDuration ExtTimeWindowDuration\n" + "albatross_v7 g_tradeStartTime ExtTimeWindowStart\n" + "double_rsi g_coeffRSIFast ExtCoeffRsiFast\n" + "double_rsi g_dayFilter ExtDayNotToTrade\n" + "double_rsi g_RSIDiffLevel ExtMinRsiDiff\n" + "double_rsi g_RSIPeriod ExtSlowRsiPeriod\n" + "double_rsi g_tradeDuration ExtTimeWindowDuration\n" + "double_rsi g_tradeStartTime ExtTimeWindowStart\n" + "double_rsi g_trend ExtTrendModeFilter\n" + "double_rsi g_volatility ExtVolatilityModeFilter\n" + "double_rsi_h4_ei g_coeffRSIFast ExtCoeffRsiFast\n" + "double_rsi_h4_ei g_dayFilter ExtDayNotToTrade\n" + "double_rsi_h4_ei g_exitParameter ExtExitParameter\n" + "double_rsi_h4_ei g_exitType ExtExitType\n" + "double_rsi_h4_ei g_RSIDiffLevel ExtMinRsiDiff\n" + "double_rsi_h4_ei g_RSIPeriod ExtSlowRsiPeriod\n" + "double_rsi_h4_ei g_tradeDuration ExtTimeWindowDuration\n" + "double_rsi_h4_ei g_tradeStartTime ExtTimeWindowStart\n" + "double_rsi_h4_ei g_trend ExtTrendModeFilter\n" + "double_rsi_h4_ei g_volatility ExtVolatilityModeFilter\n" + "hook g_CoeffExit ExtExitCoeff\n" + "hook g_Cycle ExtCycleModeFilter\n" + "hook g_CycleLevel ExtCycleLevel\n" + "hook g_CyclePeriod ExtCyclePeriod\n" + "hook g_Exit ExtExitType\n" + "hook g_Order ExtOrderMode\n" + "hook g_OrderBar ExtBarsNumber\n" + "hook g_OrderPendingBar ExtOrderDeleteBar\n" + "hook g_RSIPeriod ExtRsiPeriod\n" + "hook g_Setup ExtEntrySetup\n" + "hook g_Threshold ExtRsiThreshold\n" + "hook g_Trend ExtTrendModeFilter\n" + "hook g_TrendPeriod ExtTrendPeriod\n" + "hook g_Volatility ExtVolatilityModeFilter\n" + "hook g_TradeDuration ExtTimeWindowDuration\n" + "hook g_TradeStartTime ExtTimeWindowStart\n" + "metaphor_v5 g_barsNumber ExtBarsNumber\n" + "metaphor_v5 g_coeffBarsExit ExtExitCoeffBars\n" + "metaphor_v5 g_dayFilter ExtDayNotToTrade\n" + "metaphor_v5 g_tradeDuration ExtTimeWindowDuration\n" + "metaphor_v5 g_tradeStartTime ExtTimeWindowStart\n" + "metaphor_v6 g_barsNumber ExtBarsNumber\n" + "metaphor_v6 g_BBKCPeriod ExtBbkcPeriod\n" + "metaphor_v6 g_coeffBarsExit ExtExitCoeffBars\n" + "metaphor_v6 g_dayFilter ExtDayNotToTrade\n" + "metaphor_v6 g_tradeDuration ExtTimeWindowDuration\n" + "metaphor_v6 g_tradeStartTime ExtTimeWindowStart\n" + "metaphor_v6_quick g_barsNumber ExtBarsNumber\n" + "metaphor_v6_quick g_BBKCPeriod ExtBbkcPeriod\n" + "metaphor_v6_quick g_coeffBarsExit ExtExitCoeffBars\n" + "metaphor_v6_quick g_dayFilter ExtDayNotToTrade\n" + "metaphor_v6_quick g_tradeDuration ExtTimeWindowDuration\n" + "metaphor_v6_quick g_tradeStartTime ExtTimeWindowStart\n" + "rsi_snr g_dayFilter ExtDayNotToTrade\n" + "rsi_snr g_RSIPeriod ExtRsiPeriod\n" + "rsi_snr g_SNRLevel ExtSnrLevel\n" + "rsi_snr g_SNRPeriod ExtSnrPeriod\n" + "rsi_snr g_tradeDuration ExtTimeWindowDuration\n" + "rsi_snr g_tradeStartTime ExtTimeWindowStart\n" + "rsi_snr g_trend ExtTrendModeFilter\n" + "rsi_snr g_volatility ExtVolatilityModeFilter\n" + "rsi_snr_h1_ei g_dayFilter ExtDayNotToTrade\n" + "rsi_snr_h1_ei g_exitParameter ExtExitParameter\n" + "rsi_snr_h1_ei g_exitType ExtExitType\n" + "rsi_snr_h1_ei g_RSIPeriod ExtRsiPeriod\n" + "rsi_snr_h1_ei g_SNRLevel ExtSnrLevel\n" + "rsi_snr_h1_ei g_SNRPeriod ExtSnrPeriod\n" + "rsi_snr_h1_ei g_tradeDuration ExtTimeWindowDuration\n" + "rsi_snr_h1_ei g_tradeStartTime ExtTimeWindowStart\n" + "rsi_snr_h1_ei g_trend ExtTrendModeFilter\n" + "rsi_snr_h1_ei g_volatility ExtVolatilityModeFilter\n" + "rush_v2_h1 g_counter ExtEntrySignalCounter\n" + "rush_v2_h1 g_dayFilter ExtDayNotToTrade\n" + "rush_v2_h1 g_exitBar ExtExitBar\n" + "rush_v2_h1 g_tradeDuration ExtTimeWindowDuration\n" + "rush_v2_h1 g_tradeStartTime ExtTimeWindowStart\n" + "super_smoother_ei g_dayFilter ExtDayNotToTrade\n" + "super_smoother_ei g_DiffPeriod ExtRsiPeriodDiff\n" + "super_smoother_ei g_exitParameter ExtExitParameter\n" + "super_smoother_ei g_exitType ExtExitType\n" + "super_smoother_ei g_PeriodFast ExtFastRsiPeriod\n" + "super_smoother_ei g_tradeDuration ExtTimeWindowDuration\n" + "super_smoother_ei g_tradeStartTime ExtTimeWindowStart\n" + "super_smoother_ei g_trend ExtTrendModeFilter\n" + "super_smoother_ei g_volatility ExtVolatilityModeFilter"; final String subst = "update t_strategy\\n set t_strategy_parameters = replace(t_strategy_parameters, '$2', '$3')\\n where t_strategy_ea = '$1' and\\n t_strategy_parameters like '%$2%' and\\n t_strategy_version = '1.1';"; 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