The java.util.HashMap.containsKey() method is used to check whether a particular key is being mapped into the HashMap or not. This method compares two strings lexicographically, ignoring case differences. The second print statement displayed false because the contains() method is case sensitive. str.contains(null); Java String contains() method Example. You can change the line If strList.contains(chkStr) Then To be. This is useful for writing grammars for languages such as HTML. Description. Here is the syntax of this method â int compareToIgnoreCase(String str) (Also, remember that when you use the matches â¦ This method returns true if the strings are equal, and false if not. Problem: In a Java program, you want to determine whether a String contains a pattern, you want your search to be case-insensitive, and you want to use String matches method than use the Pattern and Matcher classes.. Despite having passed âFrEDâ as the argument, our returned list of passengers contains a Passenger with the firstName as âFredâ. On the contains method, you can specify a parameter indicating how you want to compare the strings. The idea is to convert all the strings and substring to lowercase before check with .contains() JavaExample2.java. List contains() method in Java with Examples Last Updated : 11 Dec, 2018 The contains() method of List interface in Java is used for checking if the specified element exists in the given list â¦ It takes the key element as a parameter and returns True if that element is mapped in the map. And â¦ In this example, we will show you how to check HashSet contains element case insensitive in Java.contains() method of Collection interface returns true if this set contains the specified element. String.contains() â Ignoring Case. Conclusion Clearly, with the help of the IgnoreCase keyword, we have achieved a case insensitive match. Java String FAQ: How can I tell if a Java String contains a given regular expression (regex) pattern? You don't want to manipulate the String or extract the match, you just want to determine whether the pattern exists at least one time in the given String. Check HashSet contains element case insensitive in Java. Definition and Usage. It is also possible to localize the effect of IGNORE_CASE by using an alternate mechanism described later. 5. Two strings are considered equal ignoring case, if they are of the same length Java - String equalsIgnoreCase() Method - This method compares this String to another String, ignoring case considerations. I make a censoring plugin that reads censored words from a list in a config, that works fine. In a Java program, you want to determine whether a String contains a case-insensitive regular expression (regex). By Atul Rai | July 14, 2019 Previous Next . Syntax: Hash_Map.containsKey(key_element) true false false true Hello Java 2. Syntax. The equalsIgnoreCase() method compares two strings, ignoring lower case and upper case differences.. Tip: Use the compareToIgnoreCase() method to compare two strings lexicographically, ignoring case differences. If strList.Contains(chkStr, StringComparer.OrdinalIgnoreCase) Then. IGNORE_CASE: boolean: false: Setting this option to true causes the generated token manager to ignore case in the token specifications and the input files. Solution: Use the String matches method, and include the magic (?i:X) syntax to make your search case-insensitive. You can also use the contains() method for case insensitive check, I have covered this at the end of this tutorial.