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*(lr_start_transaction.*\\))\\s*;\\s*$"; final String string = "lr_start_transaction(lr_eval_string(\"{scriptid}_0070_00000000_ASP-Hinzufuegen\");\n\n" + "Siebel_SWECount_var -= 3;\n\n" + "lr_save_int(Siebel_SWECount_var, \"Siebel_SWECount\");\n\n" + "web_save_timestamp_param(\"SiebelTimeStamp\", \n" + " LAST);\n\n" + "web_add_cookie(\"SWEUAID=6; DOMAIN={domain}\");\n\n" + "web_url(\"start.swe_60\", \n" + " \"URL={url_start}?SWECmd=ShowPopupFrames&SWEDIC=1&SWEU={url_start}%3fSWECmd%3dGetCachedFrame%26SWEC%3d47%26SWEFrame%3dtop._sweclient._swecontent._sweview._swetmp%26SRN%3d{Siebel_SRN10}%26SWESP%3d1%26SRN%3d{Siebel_SRN10}&SRN={Siebel_SRN10}\", \n" + " \"TargetFrame=\", \n" + " \"Resource=0\", \n" + " \"RecContentType=text/html\", \n" + " \"Referer=\", \n" + " \"Snapshot=t587.inf\", \n" + " \"Mode=HTML\", \n" + " LAST);\n\n" + "lr_end_transaction(lr_eval_string(\"{scriptid}_0070_00000000_ASP-Hinzufuegen\"),LR_AUTO); \n\n" + "lr_think_time(iThinktime);\n\n" + "lr_start_transaction(lr_eval_string(\"{scriptid}_0080_00000000_ASP-Hinzufuegen-Eingabe\");\n\n" + "Siebel_SWECount_var += 4;\n\n" + "lr_save_int(Siebel_SWECount_var, \"Siebel_SWECount\");\n\n" + "web_reg_find(\"Text=Error\",\"Search=Body\", \"Fail=Found\", LAST);\n\n" + "web_submit_data(\"start.swe_61\", \n" + " \"Action={url_start}\", \n" + " \"Method=POST\", \n" + " \"TargetFrame=\", \n" + " \"RecContentType=text/html\", \n" + " \"Referer=\", \n" + " \"Snapshot=t588.inf\", \n" + " \"Mode=HTML\", \n" + " \"EncodeAtSign=YES\", \n" + " ITEMDATA, \n" + " \"Name=SWEC\", \"Value={Siebel_SWECount}\", ENDITEM, \n" + " \"Name=SWEMethod\", \"Value=UpdatePrefMsg\", ENDITEM, \n" + " \"Name=SWERPC\", \"Value=1\", ENDITEM, \n" + " \"Name=SWECmd\", \"Value=InvokeMethod\", ENDITEM, \n" + " \"Name=SRN\", \"Value={Siebel_SRN10}\", ENDITEM, \n" + " \"Name=SWEIPS\", \"Value=@0*0*1*0*0*3*0*5*SWEBS1*1\", ENDITEM, \n" + " \"Name=SWEBS\", \"Value=1\", ENDITEM, \n" + " \"Name=SWEService\", \"Value=Message Bar\", ENDITEM, \n" + " LAST); "; final String subst = "\\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