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 = "(?P<syslog_date>\\S+\\s+\\d+\\s+\\d+:\\d+:\\d+)\\s+0\\s+(?P<log_date>\\d+-\\d+-\\d+T\\d+:\\s\\d+:\\d+[^\\s]+)\\s+.*?(?:(?P<device>[^\\s:]+)\\s+)?(?P<application>ora_[^\\s:]+_Audit)\\s+-\\s+-\\s+Audit\\[\\d+\\]:\\s+(?:[^]]+]\\s+)?(?:LENGTH:\\s+\\\"(?P<length>\\d+)\\\".*?)?SESSIONID:(?:\\[\\d+\\])?\\s+\\\"(?P<sessionid>\\d+)\\\".*?ENTRYID:(?:\\[\\d+\\])?\\s+\\\"(?P<entryid>\\d+)\\\".*?(?:STATEMENT:(?:\\[\\d+\\])?\\s+\\\"(?P<statement>.*?)\\\")?.*?USERID:(?:\\[\\d+\\])?\\s+\\\"(?P<userid>.*?)\\\".*?(?:USERHOST:(?:\\[\\d+\\])\\s+\"(?:(?P<host_domain>[^\\\\\"]+)\\\\+)?(?P<userhost>[^\"]*)\")?\\s+(?:TERMINAL:(?:\\[\\d+\\])\\s+\"(?P<terminal>[^\"]*)\"\\s+)?ACTION:(?:\\[\\d+\\])?\\s+\\\"(?P<action>\\d+)\\\".*?RETURNCODE:(?:\\[\\d+\\])?\\s+\\\"(?P<code>.*?)\\\".*?(?:COMMENT\\$TEXT:(?:\\[\\d+\\])?.*?\\\"Authenticated\\s+by:\\s+(?P<auth_by>\\S+)(?:\\;\\s+Client\\s+address:\\s+\\(ADDRESS\\=\\(PROTOCOL\\=tcp\\)\\(HOST\\=(?P<host>\\d+\\.\\d+\\.\\d+\\.\\d+)\\)\\(PORT\\=(?P<port>\\d+)\\)\\).*?|\"\\s+)|OBJ\\$CREATOR:(?:\\[\\d+\\])?\\s+\\\"(?P<objcreator>[^\"]*)\"\\s+.*?OBJ\\$NAME:(?:\\[\\d+\\])?\\s+\\\"(?P<objname>[^\"]*)\"\\s+)OS\\$USERID:(?:\\[\\d+\\])?\\s+\\\"(?P<osuserid>[^\"]*)\"\\s*(?:(?!PRIV\\$)\\S+\\s+)*(?:PRIV\\$USED:(?:\\[\\d+\\])?\\s+\"(?P<priv>[^\"]*)\")?"; final String string = "Mar 31 00:02:54 0 2020-03-31T00: 02:53.629415+02:00 localhost ora_AM_Audit - - Audit[29579]: LENGTH: \"379\" SESSIONID:[9] \"130549450\" ENTRYID:[1] \"1\" STATEMENT:[1] \"1\" USERID:[15] \"EFACTURA_CDATOS\" USERHOST:[9] \"EFPRE-TRX\" ACTION:[3] \"100\" RETURNCODE:[1] \"0\" COMMENT$TEXT:[102] \"Authenticated by: DATABASE; Client address: (ADDRESS=(PROTOCOL=tcp)(HOST=192.168.200.237)(PORT=44530))\" OS$USERID:[9] \"efamerica\" DBID:[10] \"3787855415\" PRIV$USED:[1] \"5\" CURRENT_USER:[15] \"EFACTURA_CDATOS\""; 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