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

r"
"
gmi

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 = "^\\s(\\w{1,}):\\s+((?:\\w\\w\\s)+)\\s+(\\w+)(.*)"; final String string = " 6bb: c3 ret \n" + " 6bc: 0f 1f 40 00 nop DWORD PTR [rax+0x0]\n" + " 6c0: 41 57 push r15\n" + " 6c2: 41 56 push r14\n" + " 6c4: 41 89 ff mov r15d,edi\n" + " 6c7: 41 55 push r13\n" + " 6c9: 41 54 push r12\n" + " 6cb: 4c 8d 25 06 07 20 00 lea r12,[rip+0x200706] # 0x200dd8\n" + " 6d2: 55 push rbp\n" + " 6d3: 48 8d 2d 06 07 20 00 lea rbp,[rip+0x200706] # 0x200de0\n" + " 6da: 53 push rbx\n" + " 6db: 49 89 f6 mov r14,rsi\n" + " 6de: 49 89 d5 mov r13,rdx\n" + " 6e1: 4c 29 e5 sub rbp,r12\n" + " 6e4: 48 83 ec 08 sub rsp,0x8\n" + " 6e8: 48 c1 fd 03 sar rbp,0x3\n" + " 6ec: e8 3f fe ff ff call 0x530\n" + " 6f1: 48 85 ed test rbp,rbp\n" + " 6f4: 74 20 je 0x716\n" + " 6f6: 31 db xor ebx,ebx\n" + " 6f8: 0f 1f 84 00 00 00 00 nop DWORD PTR [rax+rax*1+0x0]\n" + " 6ff: 00 \n" + " 700: 4c 89 ea mov rdx,r13\n" + " 703: 4c 89 f6 mov rsi,r14\n" + " 706: 44 89 ff mov edi,r15d\n" + " 709: 41 ff 14 dc call QWORD PTR [r12+rbx*8]\n" + " 70d: 48 83 c3 01 add rbx,0x1\n" + " 711: 48 39 dd cmp rbp,rbx\n" + " 714: 75 ea jne 0x700\n" + " 716: 48 83 c4 08 add rsp,0x8\n" + " 71a: 5b pop rbx\n" + " 71b: 5d pop rbp\n" + " 71c: 41 5c pop r12\n" + " 71e: 41 5d pop r13\n" + " 720: 41 5e pop r14\n" + " 722: 41 5f pop r15\n" + " 724: c3 ret \n" + " 725: 90 nop\n" + " 726: 66 2e 0f 1f 84 00 00 nop WORD PTR cs:[rax+rax*1+0x0]\n" + " 72d: 00 00 00 \n" + " 730: f3 c3 repz ret \n"; 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