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

/
/
gm

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))(?:(?<!\\s\\s)\\:\\s+)((?:[\\-\\+])?\\d+\\.\\d+|\\w+$|[\\-\\+]\\d+|\\w+\\s\\d+)"; final String string = "Beam Number : 2\n" + "Beam Name : CCW\n" + "Original MU : 1995.39040729\n\n" + "Logging Scale : IEC 1217\n" + "X1 (Cms): -2.50\n" + "X2 (Cms): +2.20\n" + "Y1 (Cms): -2.60\n" + "Y2 (Cms): +2.50\n" + "Gantry Rotation Angle (deg): 87.73\n" + "Energy : 6x\n" + "MU1 : 1007.63\n" + "MU2 : 1009.05\n" + "Radiation Time (mins): 1.6807\n" + "DoseRate (MU/min): 598.32\n" + "PFN High Voltage Power Supply Current (A): 1.908875\n" + "PFN Actual Voltage (KV): 18.21791\n" + "RF Driver Voltage (V): 4.365\n" + "RF Forward Power (W): 1.516418\n" + "AFC Error (V): -0.000601778\n" + "Gun Current (A): 0.3430939\n" + "Gun High Voltage (V): -14965\n" + "Gun Grid Voltage (V): 97.55565\n" + "Gun Filament Step Voltage (V): 5.300003\n" + "Gun Filament Voltage (V): 5.405273\n" + "Bend Magnet Current (A): 16.18042\n" + "Bend Magnet Voltage (V): 2.283325\n" + "Accelerator Solenoid Current (A): 34.95636\n" + "Klystron Solenoid Current (A): 34.95789\n" + "Radial Symmetry (%): 0.00045321\n" + "Transverse Symmetry (%): 0.00044355\n" + "Target Current (nC): 315.4927\n" + "Buncher Radial Current (A): 0.005020142\n" + "Buncher Transverse Current (A): -0.06005859\n" + "Angle Radial Current (A): 0.005279541\n" + "Angle Transverse Current (A): 0.06143188\n" + "Position Radial Current (A): -0.8885803\n" + "Position Transverse Current (A): -0.5808258\n" + "Trim : (A) -0.06399536\n" + "Accelerator Vacion Current (uA): 0.009002686\n" + "Positive 5V dc: 4.993916\n" + "Positive 24V dc: 24.4706\n" + "Analog Negative 5V dc: 5.054981\n" + "Analog Positive 5V dc: 4.97241\n" + "Negative 12V dc: 12.24357\n" + "Positive 3V dc: 3.303525\n" + "Node Power Supply Voltage (V): 24.58121\n" + "Water Level : Normal\n" + "City Water Temperature (deg C): 20.54332\n" + "Internal Water Supply Temperature (deg C): 40.51909\n" + "Gas Pressure (PSI): 32.3421"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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