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

/
/
g

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 = "(?:font)[\\ ]+([A-Za-z0-9\\=\\:]+)[\\}\\ \\}]"; final String string = "conky.config = {\n" + "-- ------------------------- Windows Settings\n" + " own_window = true,\n" + " own_window_type = 'normal',\n" + " own_window_transparent = false,\n" + " own_window_hints = 'undecorated,sticky,below,skip_taskbar,skip_pager',\n" + " own_window_argb_visual = true,\n" + " own_window_argb_value = 0,\n\n" + " double_buffer = true,\n" + " background = true,\n\n" + "-- ------------------------- Position\n" + " alignment = 'bottom_left',\n\n" + " minimum_width = 295,\n" + " minimum_height = 155,\n" + " maximum_width = 313,\n\n" + " gap_x = 1252,\n" + " gap_y = 155,\n\n" + " border_inner_margin = 0,\n" + " border_outer_margin = 0,\n" + " border_width = 0,\n\n" + "-- ------------------------- Font\n" + " use_xft = true,\n" + " xftalpha = 0.8,\n" + " override_utf8_locale = true,\n\n" + " draw_shades = true,\n" + " default_shade_color = 'black',\n\n" + " draw_borders = false,\n" + " draw_outline = false,\n\n" + " font = 'Monofur:bold:size=8',\n\n" + "-- ------------------------- Color\n" + " default_color = 'DCDCDC',\n" + " color0 = '1793d0',\n" + " color1 = 'DDDDDD',\n" + " color2 = 'AAAAAA',\n" + " color3 = '888888',\n\n" + "-- ------------------------- OTHER\n" + " update_interval = 1,\n\n" + " lua_load = '~/.conky/ConkyBar/lua/net_graph.lua',\n" + " lua_draw_hook_pre = 'main_graph',\n\n" + "};\n\n" + "conky.text = [[\n" + "${color DCDCDC}\n" + "${color DCDCDC }\n" + "${if_existing /proc/net/route enp8s0}${voffset 25}${goto 50}${font}Network${image ~/.conky/ConkyBar/img/networkhigh.png -p 0,15}\n" + "${goto 50}${font}Public ip: ${font Monofur:size=8}${texeci 36000 wget -qO - http://ip.tupeux.com | tail}\n" + "${voffset 81}${goto 50}${font}Recieve: ${font Monofur:size=8}${downspeed enp8s0}${goto 210}${font}Send: ${font Monofur:size=8}${upspeed enp8s0}${else}${if_existing /proc/net/route wlp2s0}${voffset 25}${goto 50}${font}Network\n" + "${goto 50}${font}Public ip: ${font Monofur:size=8}${texeci 36000 wget -qO - http://ip.tupeux.com | tail}${goto 210}${font}Sign: ${font Monofur:size=8}${wireless_link_qual_perc wlp2s0}%\n" + "${voffset 81}${goto 50}${font}Recieve: ${font Monofur:size=8}${downspeed wlp2s0}${goto 210}${font}Send: ${font Monofur:size=8}${upspeed wlp2s0}\n" + "${if_match \"${wireless_link_qual_perc wlp2s0}\"<\"33\"}${image ~/.conky/ConkyBar/img/networklow.png -p 0,15 -s 45x45}${else}${if_match \"${wireless_link_qual_perc wlp2s0}\"<\"66\"}${image ~/.conky/ConkyBar/img/networkmid.png -p 0,15}${else}${image ~/.conky/ConkyBar/img/networkhigh.png -p 0,15}${endif}${endif}${else}${voffset 27}${goto 50}${font}Network${image ~/.conky/ConkyBar/img/nonetwork.png -p 0,15}\n" + "${goto 50}No connection${endif}${endif}\n" + "]];"; final Pattern pattern = Pattern.compile(regex); 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