How can I remove punctuation from input text in Java?

This first removes all non-letter characters, folds to lowercase, then splits the input, doing all the work in a single line:

String[] words = instring.replaceAll("[^a-zA-Z ]", "").toLowerCase().split("\\s+");

Spaces are initially left in the input so the split will still work.

By removing the rubbish characters before splitting, you avoid having to loop through the elements.

Related Posts:

  1. How can I remove punctuation from input text in Java?
  2. How to replace ” \ ” with ” \\ ” in java
  3. Using or ‘|’ in regex [duplicate]
  4. How can I exclude one word with grep?
  5. Change date format in a Java string
  6. Split string on whitespace in Python
  7. Regex how to match an optional character
  8. What does regular expression \\s*,\\s* do?
  9. Java; String replace (using regular expressions)?
  10. Regular Expressions on Punctuation
  11. How to extract a substring using regex
  12. Regular expression – starting and ending with a character string
  13. How to use regex in String.contains() method in Java
  14. Regex empty string or email
  15. Java – Convert integer to string [duplicate]
  16. What is a Context Free Grammar?
  17. How to convert/parse from String to char in java?
  18. Java String Split by “|”
  19. How can I validate an email address using a regular expression?
  20. Regular expression to match a line that doesn’t contain a word
  21. Difference between \b and \B in regex
  22. Java string to date conversion
  23. Python regex AttributeError: ‘NoneType’ object has no attribute ‘group’
  24. Regular Expression for alphanumeric and underscores
  25. Regular Expression for alphanumeric and underscores
  26. python re.split() to split by spaces, commas, and periods, but not in cases like 1,000 or 1.50
  27. Regex to test if string begins with http:// or https://
  28. How can I prevent java.lang.NumberFormatException: For input string: “N/A”?
  29. Best way to convert an ArrayList to a string
  30. String interpolation in Java 14 or 15
  31. What is a non-capturing group in regular expressions?
  32. What is a non-capturing group in regular expressions?
  33. How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
  34. How to convert any Object to String?
  35. Remove all special characters, punctuation and spaces from string
  36. This can be done without regex:
  37. How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
  38. Symbol for any number of any characters in regex?
  39. Grep and Python
  40. Using Bash regex match (=~) where regex includes quotes (” characters)
  41. Can I multiply strings in Java to repeat sequences?
  42. Regular expression to match a word or its prefix
  43. catDog string problem at Codingbat.com
  44. What is the difference between String.subString() and String.subSequence()
  45. Java compressing Strings
  46. Question marks in regular expressions
  47. Convert array of strings into a string in Java
  48. Difference between \w and \b regular expression meta characters
  49. How to print elements from array with javascript
  50. How to remove single character from a String
  51. javascript HTML from document.body.innerHTML
  52. How can I write a regex which matches non greedy?
  53. Java split string to array
  54. Regex Explanation ^.*$ [duplicate]
  55. Negative matching using grep (match lines that do not contain foo)
  56. What does {0} mean when found in a string in C#?
  57. Regex match everything after question mark?
  58. How to check if my string is equal to null?
  59. what is Ljava.lang.String;@
  60. Converting String Array to an Integer Array
  61. How is \\n and \\\n interpreted by the expanded regular expression?
  62. How to sort an array of objects in Java?
  63. Regular Expression to reformat a US phone number in Javascript
  64. How to replace a substring of a string
  65. Immutable class?
  66. RegEx to find two or more consecutive chars
  67. RE error: illegal byte sequence on Mac OS X
  68. Regex to match an optional ‘+’ symbol followed by any number of digits
  69. Regex Match all characters between two strings
  70. Converting a string to an integer on Android
  71. Regular expression to match a word or its prefix
  72. Java: how to initialize String[]?
  73. Regular expression for a string that does not start with a sequence
  74. How to represent a fix number of repeats in regular expression?
  75. python regular expression “\1”
  76. Regular expression to stop at first match
  77. How can I remove a substring from a given String?
  78. Java get String CompareTo as a comparator object
  79. Whitespace Matching Regex – Java
  80. /bb|[^b]{2}/ how does it work?
  81. How to swap String characters in Java?
  82. Get an OutputStream into a String
  83. Difference between string object and string literal
  84. How do I match any character across multiple lines in a regular expression?
  85. Regular expression to remove HTML tags from a string
  86. Regular expression to limit number of characters to 10
  87. My Vim replace with a regex is throwing a `E488: Trailing characters`
  88. Append a single character to a string or char array in java?
  89. String is immutable. What exactly is the meaning?
  90. Regex to validate date formats dd/mm/YYYY, dd-mm-YYYY, dd.mm.YYYY, dd mmm YYYY, dd-mmm-YYYY, dd/mmm/YYYY, dd.mmm.YYYY with Leap Year Support
  91. Regex difference: (\w+)? and (\w*)
  92. Java regex email
  93. How to know if a given string is substring from another string in Java
  94. 404 regular-expression advice needed
  95. How to use a variable as a className inside preg_match_all parameters?
  96. Adding span tags to post titles using regex
  97. Remove Custom HTML Posts Using Regex
  98. Regexes allow only [a-z][A-Z][0-9] and –
  99. Call Shortcode Attribute Value within another function
  100. Use Regex Redirection via htsaccess for RSS Feeds WordPress

Leave a Comment

tech