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

$re = '/(public|protected|private|static|\s) +[\w\<\>\[\]]+\s+(\w+) *\([^\)]*\)\s*(\{)/'; $str = '/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.pdfbox.pdmodel.interactive.documentnavigation.outline; import org.apache.pdfbox.cos.COSDictionary; import org.apache.pdfbox.cos.COSName; /** * This represents an outline in a pdf document. * * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a> * @version $Revision: 1.2 $ */ public final class PDDocumentOutline extends PDOutlineNode { static java.io.BufferedWriter bfn; static java.io.BufferedWriter bf; /** * Default Constructor. */ public PDDocumentOutline() { getCOSDictionary().setName(COSName.TYPE, COSName.OUTLINES.getName()); } /** * Constructor for an existing document outline. * * @param dic The storage dictionary. */ public PDDocumentOutline( COSDictionary dic ) { super( dic ); getCOSDictionary().setName(COSName.TYPE, COSName.OUTLINES.getName()); } @Override public boolean isNodeOpen() { return true; } @Override public void openNode() { // The root of the outline hierarchy is not an OutlineItem and cannot be opened or closed } @Override public void closeNode() { // The root of the outline hierarchy is not an OutlineItem and cannot be opened or closed } } '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php