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

/
/
ig

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 = "\\b(FLOWLINKMEDIA ID=)"; final String string = "<FLOWLINKMEDIA ID=\"LDP_COMPLETE\">\n" + " <PART NAME=\"MAIN\">\n" + " <GRPH ZORDER=\"0\" W=\"4000\" H=\"3000\">\n" + " <SOURCE>back01.png</SOURCE>\n" + " </GRPH>\n" + " <GRPH ZORDER=\"1\" TP=\"#00FF00\">\n" + " <SOURCE LOCATION=\"VAR\">MKTAD:MAIN_TILE</SOURCE>\n" + " </GRPH>\n" + " </PART>\n" + " <PART NAME=\"OMP\">\n" + " <REGION NAME=\"REQUEST_BOTTOM\">\n" + " <TEXTBOX STYLE=\"REQUEST_PROMPT\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:INF_ONEMOMENT</SOURCE>\n" + " </TEXTBOX>\n" + " </REGION>\n" + " </PART>\n" + " </FLOWLINKMEDIA>\n\n" + " <FLOWLINKMEDIA ID=\"LDP_DEPOSITMENU\">\n" + " <SM NAME=\"SMDL\" />\n" + " <PART NAME=\"MAIN\">\n" + " <GRPH ZORDER=\"0\" W=\"4000\" H=\"3000\">\n" + " <SOURCE>back01.png</SOURCE>\n" + " </GRPH>\n" + " <REGION NAME=\"MARKETING_BANNER\">\n" + " <GRPH ZORDER=\"1\" TP=\"#00FF00\">\n" + " <SOURCE LOCATION=\"VAR\">MKTAD:OPENER_TILE</SOURCE>\n" + " </GRPH>\n" + " </REGION>\n" + " <REGION NAME=\"MAIN\">\n" + " <TEXTBOX STYLE=\"LINE1_LARGEPROMPT_WIDE\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:PRM_INT_LDPMENU</SOURCE>\n" + " </TEXTBOX>\n" + " <SPEECH SCR_COMP=\"PROMPT\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:TTS_PAUSE</SOURCE>\n" + " </SPEECH>\n" + " <TEXTBOX STYLE=\"PROMPT_SUBTEXT\">\n" + " <VARSOURCE>\n" + " <SOURCE LOCATION=\"VAR\">LANG:INF_BCREFERENCE</SOURCE>\n" + " <VAR NAME=\"BCTOACCT\">\n" + " <SOURCE LOCATION=\"VAR\">BUSOBJ:USERDATA\\TOACCT\\NAME_NUMBER</SOURCE>\n" + " </VAR>\n" + " </VARSOURCE>\n" + " </TEXTBOX>\n" + " <SPEECH SCR_COMP=\"PROMPT\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:TTS_PAUSE</SOURCE>\n" + " </SPEECH>\n" + " </REGION>\n" + " </PART>\n" + " <PART NAME=\"NAV_BAR\">\n" + " <REGION NAME=\"NAVIGATION_BAR\">\n" + " <GRPH ZORDER=\"1\" TP=\"#00FF00\">\n" + " <SOURCE>nav_bar.png</SOURCE>\n" + " </GRPH>\n" + " </REGION>\n" + " </PART>\n" + " <PART NAME=\"CANCEL\">\n" + " <ACTIONKEY VALUE=\"CANCEL\"/>\n" + " <REGION NAME=\"NAVIGATION_BAR_LEFT_BTN\" TOUCH=\"Y\">\n" + " <GRPH ZORDER=\"2\" Y=\"80\" X=\"90\">\n" + " <SOURCE>nav_exit.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"NAVBAR_LEFT_OPTION\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:FDK_CANCEL</SOURCE>\n" + " </TEXTBOX>\n" + " </REGION>\n" + " </PART>\n" + " <PART NAME=\"TYPE_PANEL\">\n" + " <REGION NAME=\"MAIN_PANEL\" TOUCH=\"N\">\n" + " <GRPH ZORDER=\"1\">\n" + " <SOURCE>main_panel.png</SOURCE>\n" + " </GRPH>\n" + " </REGION>\n" + " </PART>\n" + " <DISPLAYLIST LISTNAME=\"DEPTYPE\" EVENTNAME=\"FE_SELECTED\">\n" + " <POSITIONS>\n" + " <POS REGION_NAME=\"MAIN_PANEL_1OF3\" TOUCH=\"Y\">\n" + " <SPITEM ITEMNAME=\"SHOW\" ENABLEINPUT=\"Y\">\n" + " <GRPH ZORDER=\"3\">\n" + " <SOURCE>primary_tile_1.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\">\n" + " <VARSOURCE LOCATION=\"VAR\">\n" + " <SOURCE>LANG:INF_LDPMENU_</SOURCE>\n" + " <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE>\n" + " </VARSOURCE>\n" + " </TEXTBOX>\n" + " </SPITEM>\n" + " <SPITEM ITEMNAME=\"GHOST\" ENABLEINPUT=\"N\">\n" + " <GRPH ZORDER=\"1\" TP=\"#00FF00\">\n" + " <SOURCE>primary_tile_1_ghost.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_1OF2\">\n" + " <VARSOURCE LOCATION=\"VAR\">\n" + " <SOURCE>LANG:INF_LDPMENU_</SOURCE>\n" + " <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE>\n" + " </VARSOURCE>\n" + " </TEXTBOX>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_2OF2\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:MENU_TEMP_UNAVAILABLE</SOURCE>\n" + " </TEXTBOX>\n" + " </SPITEM>\n" + " <SPITEM ITEMNAME=\"HIDE\" ENABLEINPUT=\"N\"/>\n" + " <RESPONSE DISPLAYTIME=\"100\">\n" + " <GRPH ZORDER=\"0\" TP=\"#00FF00\">\n" + " <SOURCE>Highlight\\primary_tile_1.png</SOURCE>\n" + " </GRPH>\n" + " </RESPONSE>\n" + " </POS>\n" + " <POS REGION_NAME=\"MAIN_PANEL_2OF3\" TOUCH=\"Y\">\n" + " <SPITEM ITEMNAME=\"SHOW\" ENABLEINPUT=\"Y\">\n" + " <GRPH ZORDER=\"3\">\n" + " <SOURCE>primary_tile_1.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\">\n" + " <VARSOURCE LOCATION=\"VAR\">\n" + " <SOURCE>LANG:INF_LDPMENU_</SOURCE>\n" + " <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE>\n" + " </VARSOURCE>\n" + " </TEXTBOX>\n" + " </SPITEM>\n" + " <SPITEM ITEMNAME=\"GHOST\" ENABLEINPUT=\"N\">\n" + " <GRPH ZORDER=\"1\" TP=\"#00FF00\">\n" + " <SOURCE>primary_tile_1_ghost.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_1OF2\">\n" + " <VARSOURCE LOCATION=\"VAR\">\n" + " <SOURCE>LANG:INF_LDPMENU_</SOURCE>\n" + " <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE>\n" + " </VARSOURCE>\n" + " </TEXTBOX>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_2OF2\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:MENU_TEMP_UNAVAILABLE</SOURCE>\n" + " </TEXTBOX>\n" + " </SPITEM>\n" + " <SPITEM ITEMNAME=\"HIDE\" ENABLEINPUT=\"N\"/>\n" + " <RESPONSE DISPLAYTIME=\"100\">\n" + " <GRPH ZORDER=\"0\" TP=\"#00FF00\">\n" + " <SOURCE>Highlight\\primary_tile_1.png</SOURCE>\n" + " </GRPH>\n" + " </RESPONSE>\n" + " </POS>\n" + " <POS REGION_NAME=\"MAIN_PANEL_3OF3\" TOUCH=\"Y\">\n" + " <SPITEM ITEMNAME=\"SHOW\" ENABLEINPUT=\"Y\">\n" + " <GRPH ZORDER=\"3\">\n" + " <SOURCE>primary_tile_1.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\">\n" + " <VARSOURCE LOCATION=\"VAR\">\n" + " <SOURCE>LANG:INF_LDPMENU_</SOURCE>\n" + " <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE>\n" + " </VARSOURCE>\n" + " </TEXTBOX>\n" + " </SPITEM>\n" + " <SPITEM ITEMNAME=\"GHOST\" ENABLEINPUT=\"N\">\n" + " <GRPH ZORDER=\"1\" TP=\"#00FF00\">\n" + " <SOURCE>primary_tile_1_ghost.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_1OF2\">\n" + " <VARSOURCE LOCATION=\"VAR\">\n" + " <SOURCE>LANG:INF_LDPMENU_</SOURCE>\n" + " <SOURCE LOCATION=\"DISPLAYLIST\">VALUE</SOURCE>\n" + " </VARSOURCE>\n" + " </TEXTBOX>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER_2OF2\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:MENU_TEMP_UNAVAILABLE</SOURCE>\n" + " </TEXTBOX>\n" + " </SPITEM>\n" + " <SPITEM ITEMNAME=\"HIDE\" ENABLEINPUT=\"N\"/>\n" + " <RESPONSE DISPLAYTIME=\"100\">\n" + " <GRPH ZORDER=\"0\" TP=\"#00FF00\">\n" + " <SOURCE>Highlight\\primary_tile_1.png</SOURCE>\n" + " </GRPH>\n" + " </RESPONSE>\n" + " </POS>\n" + " </POSITIONS>\n" + " <SMDEFINED>\n" + " <SMITEM SMNAME=\"MORE\" EVENTNAME=\"MORE\">\n" + " <GRPH ZORDER=\"1\" TP=\"#00FF00\">\n" + " <SOURCE>primary_tile_1.png</SOURCE>\n" + " </GRPH>\n" + " <TEXTBOX STYLE=\"PRIMARY_TILE1_CENTER\">\n" + " <SOURCE LOCATION=\"VAR\">LANG:FDK_MOREACCTS</SOURCE>\n" + " </TEXTBOX>\n" + " </SMITEM>\n" + " </SMDEFINED>\n" + " </DISPLAYLIST>\n" + " </FLOWLINKMEDIA>"; final Pattern pattern = Pattern.compile(regex, 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