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
Processing...

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 = "(new=\\\"\\w+\\\").*(info=\\\"\\w+\\\")"; final String string = "<hello script=\"2.5\">\n" + "<welcome>\n" + " <hgsdhjaghjdghjagdjhgjdhgdajhgdajhgdhjjgfkjg\n" + " <number new=\"0x0000-0x3FF\" Id=\"bhi\" Range=\"4\" no_id=\"hello\" />\n" + " \n" + " < ----jsdjhsdjndkjjdhjdJHksdkjdnknnddnekfgrejgjorgj jregjgkrjglrjgojggjorjg -- >\n" + " < number new=\"0x02\" Id=\"bhi\" Unit=\"0\" Range=\"4\" info=\"0x00000012\" no_id=\"hi all\" />\n" + " < number new=\"0x04\" Id=\"bhi\" Unit=\"0\" Range=\"4\" info=\"0x0000023f\" no_id=\"dbhwd\" />\n" + " < ---- dfiuhdwiudi iwqdidffenfj odwqjdjqwgru jdqkkjwfkjfwn odHHOIJD JSDNKS nsk---- >\n" + " < number new=\"0x06\" Id=\"bhi\" Unit=\"0\" Range=\"4\" info=\"0x00000f22\" no_id=\"sjkdnkl jdsnj\" />\n" + " < number new=\"0x08\" Id=\"bhi\" Unit=\"0\" Range=\"4\" info=\"0x00000f1b\" no_id=\"dm o\" />\n" + " < -- bdheuh jwdhjwdkiwh ---- >\n" + " < number new=\"0x32\" Id=\"bhi\" Range=\"4\" info=\"0x000012f5\" no_id=\"he d kd\" />\n" + " < number new=\"0x336\" Id=\"bhi\" Range=\"4\" info=\"0x00000df2\" no_id=\"dnkwn\" />\n" + " < number new=\"0x428\" Id=\"bhi\" Range=\"4\" info=\"0x0001cbf2\" no_id=\"h nd\" />\n" + "< -- new model vdhjsb ---- >\n" + " < number new=\"0x06\" Id=\"bhi\" Unit=\"0\" unit_id=\"hi_all\" Range=\"2\" info=\"0x0f22\" no_id=\"sjkdnkl jdsnj' />\n" + " < number new=\"0x08\" Id=\"bhi\" Unit=\"0\" unit_id=\"this new\" Range=\"4\" info=\"0x00000f1b\" no_id=\"dm o\" /\n\n" + "< --- adhhj jdwjdkkj jsSDjkasdj jefnflefk kjsjfoekfle kajfofkp ksaokdfpef ---- >\n" + "< -- the end of file---- >"; 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