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

/
/
s

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 = "desc\\s*\"(((?!\").)*)((?!\\n).)*\\n{1}task\\s*:(((?!\\n).)*)do(((?!\\nend).)*)\\nend"; final String string = "import 'cloud2/cloud2.rb'\n" + "desc \"transfer db from current location to local and new dev\"\n" + "task :fulldbtransfer => [ \n" + " :dbdown, :dbup, \n" + " :dbup_live,]\n" + "$comps_db = ['prube_yalecomps']\n" + "$tnew_dbs = [ 'prube_yaletnew_drama_prod',\n" + " 'prube_yaletnew_summer_cabaret_prod',\n" + " 'prube_yaletnew_cabaret_prod',\n" + " 'prube_yaletnew_music_prod',\n" + " 'prube_yaletnew_rep_prod']\n" + "$new_tnew_dbs = [ 'prube_yaletnew_drama',\n" + " 'prube_yaletnew_summer_cabaret',\n" + " 'prube_yaletnew_cabaret',\n" + " 'prube_yaletnew_music',\n" + " 'prube_yaletnew_rep']\n" + "all_erube_dbs = $comps_db + $tnew_dbs\n" + "desc \"Transfer Database, complete with tunnel setup and teardown\"\n" + "task :dbdown do\n" + " all_erube_dbs.each do |database_name|\n" + " cloud2_mysqldump do tunnel_host 'cumulus-www-master-pub.rs.lynch2.com'\n" + " tunnel_user 'www' db_host 'cumulus-db-master.rs.lynch2.com' skip_secure_auth true \n" + " db_user 'mysql'\n" + " db_pass 'mysql'\n" + " db_name \" file_prefix 'SOURCE_'\n" + " ignored_tables ['cache','hits','debug','sessionvars','sessions']\n" + " end \n" + " end\n" + "end\n\n" + "task :dbsandr do\n" + " dbname = \"prube_yalecomps\"\n" + " bucket_prefix = \"comps\"\n" + " cloud2_sed do\n" + " source_file \"db-tools/SOURCE_mysqldump_ dest_file \"db-tools/CLOUD2_ \n" + " find_str [ ]\n\n" + " replace_str [ ] end\n\n" + " dbname = \"prube_yaletnew_drama_prod\"\n" + " bucket_prefix = \"drame\"\n" + " cloud2_sed do\n" + " source_file \"db-tools/SOURCE_mysqldump_ dest_file \"db-tools/CLOUD2_ \n" + " find_str [\n" + " 'prube_yaletnew_drama_prod', ]\n\n" + " replace_str [\n" + " \"prube_yaletnew_drama\", ] end\n\n" + " dbname = \"prube_yaletnew_summer_cabaret_prod\"\n" + " bucket_prefix = \"summer-cabaret\"\n" + " cloud2_sed do\n" + " source_file \"db-tools/SOURCE_mysqldump_ dest_file \"db-tools/CLOUD2_ \n" + " find_str [\n" + " 'prube_yaletnew_summer_cabaret_prod', ]\n\n" + " replace_str [\n" + " 'prube_yaletnew_summer_cabaret', ] end\n\n\n" + " dbname = \"prube_yaletnew_cabaret_prod\"\n" + " bucket_prefix = \"cabaret\"\n" + " cloud2_sed do\n" + " source_file \"db-tools/SOURCE_mysqldump_ dest_file \"db-tools/CLOUD2_ \n" + " find_str [\n" + " 'prube_yaletnew_cabaret_prod', ]\n\n" + " replace_str [\n" + " 'prube_yaletnew_cabaret', ] end\n\n" + " dbname = \"prube_yaletnew_music_prod\"\n" + " bucket_prefix = \"music\"\n" + " cloud2_sed do\n" + " source_file \"db-tools/SOURCE_mysqldump_ dest_file \"db-tools/CLOUD2_ \n" + " find_str [\n" + " 'prube_yaletnew_music_prod', ]\n\n" + " replace_str [\n" + " 'prube_yaletnew_music', ] end\n\n" + " dbname = \"prube_yaletnew_rep_prod\"\n" + " bucket_prefix = \"rep\"\n" + " cloud2_sed do\n" + " source_file \"db-tools/SOURCE_mysqldump_ dest_file \"db-tools/CLOUD2_ \n" + " find_str [\n" + " 'prube_yaletnew_rep_prod', ]\n\n" + " replace_str [\n" + " 'prube_yaletnew_rep', ] end\n\n" + "end\n\n\n\n" + "desc \"Send Database to tigard-dev-rds\"\n" + "task :dbup do\n" + " upload_dbs \"reston-dev-rds.aws.lynch2.com\"\n" + "end\n\n" + "desc \"Send Database to tigard-mail2-rds\"\n" + "task :dbup_live do\n" + " upload_dbs \"reston-live-rds.aws.lynch2.com\"\n" + "end\n\n" + "def upload_dbs (dbhost)\n" + " $comps_db.each do |database_name| \n" + " cloud2_mysql do db_host dbhost\n" + " db_user 'mysql'\n" + " db_pass 'mysql'\n" + " db_name \"mysql\" sql_files [\"CLOUD2_ end \n" + " cloud2_mysql do db_host dbhost\n" + " db_user 'mysql'\n" + " db_pass 'mysql'\n" + " db_name \" sql_files [\"erube_upgrade.sql\"]\n" + " end \n" + " end\n" + " $new_tnew_dbs.each do |database_name| \n" + " cloud2_mysql do db_host dbhost\n" + " db_user 'mysql'\n" + " db_pass 'mysql'\n" + " db_name \"mysql\" sql_files [\"CLOUD2_ end \n" + " cloud2_mysql do db_host dbhost\n" + " db_user 'mysql'\n" + " db_pass 'mysql'\n" + " db_name \" sql_files [\"tnew_erube_upgrade.sql\"]\n" + " end \n" + " end\n" + "end\n"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); final Matcher matcher = pattern.matcher(string); if (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