Regular expression date pattern (0?[1-9]|[12][0-9]|3[01])/(0?[1-9]|1[012])/((19|20)\d\d)(0?[1-9]|[12][0-9]|3[01])/(0?[1-9]|1[012])/((19|20)\d\d) This regular expression refers to a pattern which validates the date in dd/mm/yyyy pattern. Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern;   public class RegexTest { private static final String PATTERN = "(0?[1-9]|[12][0-9]|3[01])/(0?[1-9]|1[012])/((19|20)\d\d)"; public static boolean validate(final String date){ Pattern pattern = Pattern.compile(PATTERN); Matcher matcher … Read more

Regular expression time in 24 hours format pattern ([01]?[0-9]|2[0-3]):[0-5][0-9]([01]?[0-9]|2[0-3]):[0-5][0-9] This regular expression refers to a pattern which start from 0-23 or 00-23 then a semi colon (:) and follow by 00-59. Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern;   public class RegexTest { private static final String PATTERN = "([01]?[0-9]|2[0-3]):[0-5][0-9]"; … Read more

Regular expression time in 12 hours format pattern (1[012]|[1-9]):[0-5][0-9](\s)?(?i)(am|pm)(1[012]|[1-9]):[0-5][0-9](\s)?(?i)(am|pm) This regular expression refers to a pattern which start from 0-12, then a semi colon (:) and follow by 00-59, and end with am or pm. Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern;   public class RegexTest { private static final … Read more

Regular expressions Regular expressions represents a sequence of symbols and characters expressing a string or pattern to be searched for within a longer piece of text. The abbreviation for regular expression is regex. In programming regular expressions are mainly used to define constraint on strings like password, email validation. Regular expression ip address pattern ^([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\. … Read more

Regular expression image file extension pattern ([^\s]+(\.(?i)(jpg|png|gif|bmp))$)([^\s]+(\.(?i)(jpg|png|gif|bmp))$) This regular expression refers to a pattern which must have 1 or more strings (but not white space), follow by dot “.” and string end in “jpg” or “png” or “gif” or “bmp”, and the file extensive is case-insensitive. Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import … Read more

Regular expression hex code pattern #([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})$ This regular expression refers to a pattern which must start with a “#” symbol, follow by a letter from “a” to “f”, “A” to “Z” or a digit from “0” to 9″ with exactly 6 or 3 length. Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import … Read more

Regular expression password pattern ((?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%]).{6,15})((?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%]).{6,15}) This regular expression refers to a pattern with at least one digit, one upper case letter, one lower case letter and one special symbol (“@#$ Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern;   public class RegexTest { private static final String PATTERN = "((?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%]).{6,15})"; public … Read more

Regular expression email pattern ^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9]+)*(\.[A-Za-z]{2,})$^[_A-Za-z0-9-\+]+(\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\.[A-Za-z0-9]+)*(\.[A-Za-z]{2,})$ This regular expression refers to a pattern which must start with “_A-Za-z0-9-\+” , optional follow by “.[_A-Za-z0-9-]”, and end with a “@” symbol. The email’s domain name must start with “A-Za-z0-9-“, follow by first level Tld (.com, .net) “.[A-Za-z0-9]” and optional follow by a second level Tld (.com.au, .com.my) “\.[A-Za-z]{2,}”, … Read more

Regular expression username pattern ^[a-z0-9_-]{5,15}$^[a-z0-9_-]{5,15}$ This regular expression refers to a pattern which accepts 5 to 15 characters with any lower case character, digit or special symbol “_-” only. Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern;   public class RegexTest { private static final String PATTERN = "^[a-z0-9_-]{5,15}$"; public static … Read more

Regular expression to accept only alphabets [a-zA-Z]+\.?[a-zA-Z]+\.? This regular expression refers to a pattern which accepts alphabets only. Example package com.w3schools;   import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern;   public class RegexTest { private static final String PATTERN = "[a-zA-Z]+\.?"; public static void main(String args[]){ List<String> values = new ArrayList<String>(); values.add("Jai"); values.add("Jai5"); values.add("12345"); … Read more