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 = "(<Group id=\"\\d+\">\\n\\t\\t\\t<Name>)(\\w+)_(\\w+)(<\\/Name>\\n\\t\\t\\t<Description>)([\\w+\\s]+)\\s-\\s([\\w+\\s]+)(<\\/Description>)"; final String string = " <Group id=\"100\">\n" + " <Name>generalAlarm_Group01</Name>\n" + " <Description>Group General Alarm 01</Description>\n" + " <Type>poll</Type>\n" + " <Content multipleGet=\"true\">\n" + " <Param>100</Param>\n" + " <Param>101</Param>\n" + " <Param>103</Param>\n" + " <Param>104</Param>\n" + " <Param>120</Param>\n" + " <Param>121</Param>\n" + " </Content>\n" + " </Group>\n" + " <Group id=\"110\">\n" + " <Name>generalConfig_Group01</Name>\n" + " <Description>Group General Config 01</Description>\n" + " <Type>poll</Type>\n" + " <Content multipleGet=\"true\">\n" + " <Param>105</Param>\n" + " <Param>106</Param>\n" + " <Param>107</Param>\n" + " <Param>108</Param>\n" + " <Param>109</Param>\n" + " <Param>110</Param>\n" + " <Param>111</Param>\n" + " <Param>112</Param>\n" + " <Param>113</Param>\n" + " </Content>\n" + " </Group>\n" + " \n" + " <Group id=\"1000\">\n" + " <Name>firstPriorityAlarmConfig_Group1000</Name>\n" + " <Description>First Priority Alarm Config Table - Group 1000</Description>\n" + " <Type>poll</Type>\n" + " <Content multipleGet=\"true\">\n" + " <Param>1000</Param>\n" + " </Content>\n" + " </Group>\n" + " <Group id=\"2000\">\n" + " <Name>secondPriorityAlarmConfig_Group2000</Name>\n" + " <Description>Second Priority Alarm Config Table - Group 2000</Description>\n" + " <Type>poll</Type>\n" + " <Content multipleGet=\"true\">\n" + " <Param>2000</Param>\n" + " </Content>\n" + " </Group>\n" + " <Group id=\"3000\">\n" + " <Name>thirdPriorityAlarmConfig_Group3000</Name>\n" + " <Description>Third Priority Alarm Config Table - Group 3000</Description>\n" + " <Type>poll</Type>\n" + " <Content multipleGet=\"true\">\n" + " <Param>3000</Param>\n" + " </Content>\n" + " </Group>"; final String subst = "$1$3_$2$4$6 - $5$7"; 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