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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

"
"
gmi

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(aS)\\s+((\\`)?\\w+(\\`)?)(\\s+|\\,|(FRom\\s+))"; final String string = " SELECT \n" + " a.WORKORDER_NO AS workOrderNo, \n" + " a.ORD_TYPE AS ordType, \n" + " a.ORD_NO AS ordNo, \n" + " a.RETURN_FLAG AS returnFlag, \n" + " a.AREA_ID AS areaId, \n" + " a.USER_NAME AS userName, \n" + " a.ADDR_DETAIL AS addrDetail, \n" + " a.HANDLE_STAFF_ID AS handleStaffId, \n" + " a.TAKE_STAFF_ID AS takeStaffId, \n" + " a.TAKE_TS AS takeTs, \n" + " a.RETURN_STAFF_ID AS returnStaffId, \n" + " a.RETURN_TS AS returnTs, \n" + " a.SUMMARY AS summary, \n" + " a.WO_TITLE AS woTitle, \n" + " a.INSTALL_FLAG AS installFlag, \n" + " a.START_TS AS startTs, \n" + " a.END_TS AS endTs, \n" + " a.GRID_ID AS gridId, \n" + " a.SCHEMA_ID AS schemaId, \n" + " a.PROJECT_ID AS projectId, \n" + " a.COMMENTS AS comments, \n" + " a.STATE AS `state`, \n" + " a.CREATE_USER AS createUser, \n" + " a.CREATE_DATE AS createDate, \n" + " a.MODIFY_USER AS modifyUser, \n" + " a.MODIFY_DATE AS modifyDate, \n" + " a.HANDLE_TEAM_ID AS handleTeamId, \n" + " a.PACKAGE_ID AS packageId, \n" + " a.PACKAGE_NAME AS packageName, \n" + " a.SUB_TYPE AS subType, \n" + " a.pre_work_order_no AS preWorkOrderNo, \n" + " a.IS_SYNC AS isSync, \n" + " a.IS_VIRTUAL AS isVirtual, \n" + " a.VIRTUAL_WORKORDER_NO AS virtualWorkOrderNo, \n" + " a.VIRTUAL_WORKORDER_RES_ID AS virtualWorkOrderResId, \n" + " a.IS_POLE AS isPole, \n" + " a.VER_NO AS verNo, \n" + " a.TASK_ID AS taskId, \n" + " \n" + " b.USER_NAME AS userName \n" + " \n" + " FROM oss_edn.edn_work_order a \n" + " LEFT JOIN oss_wfm.wfs_user_infor b ON a.HANDLE_STAFF_ID = b.USER_ID \n" + " WHERE a.WORKORDER_NO = :workOrderNo"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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