In this tutorial, you will learn about the Java compareToIgnoreCase() method with the help of examples. boolean containsIgnoreCase(java.lang.String, java.lang.String) Tests if an input string contains the specified substring in a case insensitive way. A big drawback of using toLowerCase() is that the outcome depends on the current Locale. You can use regular expressions, and it works: Here's some Unicode-friendly ones you can make if you pull in ICU4j. This answer has already been suggested in many of the other, more detailed answers to this question that others have provided. Assume we have a file named sample.txt in the D directory with the following content −. Each iteration checks to see if the substring of the container string is equalsIgnoreCase to the sub. How do I convert a String to an int in Java? @MattQuail there's no point in it being faster if it may be incorrect. see @Adriaan Koster comment. @user01 I performed a speed analysis. But it's hopefully locale-dependent in a way the user would expect. How to check whether an input string contains a specified substring ignoring the case using JSP? This speed analysis does not mean to be rocket science, just a rough picture of how fast the different methods are. And there is not StringComparison parameter available similar to Equals() method, which helps to compare case insensitive. Using this string will be checked with ignoring the case. There are many ways to check if a String contains a substring. Java String equalsIgnoreCase Method: The equalsIgnoreCase() Method is used to compare a specified String to another String, ignoring case considerations. boolean result1 = str2.equalsIgnoreCase ... Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. To find whether a String contains a particular sub string irrespective of case −. I would probably prefer that style for lower complexity, too. The Java String equalsIgnoreCase() method compares two strings, ignoring case differences. Stack Overflow for Teams is a private, secure spot for you and When using the contains method, you want to see if one string is contained in the other. What are the key ideas of a good bassline? Is it my fitness level or my single-speed bicycle? Well, you don't say what language you are talking about, but I would assume either Java or C#. Where did all the old discussions on Google Groups actually come from? I can do this with: I am pretty sure that contains() is case sensitive, however I can't determine this for sure from reading the documentation. In this tutorial, you will learn about the Java equalsIgnoreCase() method with the help of examples. How do I make the first letter of a string uppercase in JavaScript? For case insensitive check, we can change both the strings to either upper case or lower case before calling the contents() method. when using the contains method, you want to see if one string is contained in the other. Check if a string contains a number using Java. Does anybody know if this respects locale? 19 answers ; Source. Do firbolg clerics have access to the giant pantheon? If you look at the for loop, you will see that it iterates in substrings (that are the length of the "sub") over the container string. In either case something like this should work (in Java): string toSearch = "Some String Containing Data and Other Things"; string toFind = "DATA"; boolean found = toSearch.toLowerCase( ).contains( toFind.toLowerCase( ) ); It is like equals() method but doesn't check case. Following Java example reads a sub string from the user an verifies whether the file contains the given sub string irrespective of case. boolean containsIgnoreCase(java.lang.String, java.lang.String) Example. The toLoweCase() method of the String class converts all the characters in the current String into lower case and returns. - Trejkaz Under what conditions does a Martial Spellcaster need the Warcaster feat to comfortably cast spells? – Eric Feb 20 '13 at 4:29. when using the contains method, you want to see if one string is contained in the other. Solution: Use the String matches method, and include the magic (?i:X) syntax to make your search case-insensitive. It returns a boolean value which is − true, if the source string contains the search string. How to check if a string contains only lower case letters in Python? For example, the Greek capital sigma has two lowercase forms (depending on whether it comes at the end of a word or not) and when attempting to do case-insensitive substring match, where the substring ends with a sigma, you could easily get incorrect results. Java String FAQ: How can I tell if a Java String contains a given regular expression (regex) pattern? There is a simple concise way, using regex flag (case insensitive {i}): Basically, it is a method that takes two strings. Garrett's suggestion will be much more reliable. How do I check if a string contains a specific word? Lets take an example to understand this: If any character is not matched, it returns false otherwise it returns true. And this particular one may be better than regular expressions as regex is always expensive in terms of performance. Any way to automatically mark sharps where edges of UV maps are? str1.toLowerCase().contains(str2.toLowerCase()) //Return true Nice catch Matt. String.contains() – Case Sensitive That won't work if the set contains a string with mixed case, like "Amandeep". What is the alternative for String.contains method that is case insensitive? make - java string matches ignore case . If you're interested how the analysis was performed, here is the complete runnable application: A simpler way of doing this (without worrying about pattern matching) would be converting both Strings to lowercase: This code will return the String "TRUE!" Could all participants of the recent Capitol invasion be charged over the death of Officer Brian D. Sicknick? Invoke the contains() method on the fileContents by passing subString as a parameter to it. java - String contains - ignore case. Most importantly, we'll provide examples of how to solve this issue. 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 … he is asking how to match case sensitive strings. Your solution is simpler thant any of the ones in the answers. Is it damaging to drain an Eaton HS Supercapacitor below its minimum working voltage? Check if String starts with given characters regardless of upper case, lower case, How to make IgnoreCase when you're using the contain method, How to check if a string contains a substring in Bash. Check if a string contains a sub-string in C++. These are the top rated real world Java examples of StringUtils.containsIgnoreCase extracted from open source projects. Ignore case for 'contains' for a string in Java. The fn:containsIgnoreCase() function determines whether an input string contains a specified substring. In a Java program, you want to determine whether a String contains a case-insensitive regular expression (regex). Java - String equalsIgnoreCase() Method - This method compares this String to another String, ignoring case considerations. It (being slow) doesn't matter if you just want to check in one case. 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. How to check whether a string contains a substring in JavaScript? The Apache Commons library is very useful for this sort of thing. By Atul Rai | July 14, 2019 Previous Next . @You should probably add that to your answer. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Comparing "foobar" and "FOO" will always match, however if you are comparing user-input information, or language-specific content, then you are right - a developer should be cautious. Character case is language dependent, which means it will work on your computer but will fail for the customer :). We will see Spring Data JPA contains ignorecase Example using Spring Boot and oracle. I've tested icza's method and mine for the speed and here are the results: We can use stream with anyMatch and contains of Java 8. or you can use a simple approach and just convert the string's case to substring's case and then use contains method. The answer I and Many here, are looking for is in your question. The Simplest Solution: String.toLowerCase This tag is used to check that given string contains the specified sub string or not. If it is then I suppose my best method would be something like: All this aside, is there another (possibly better) way to accomplish this without caring about case-sensitivity? I've corrected my answer since it is the first one people will see, but vote up Matt Quail's since he pointed this out. Translate. (Also, remember that when you use the matches method, your … Java String equalsIgnoreCase() Method String Methods. Translate. I guess "ignore case" is questionable for the method names because although primary strength comparisons do ignore case, it's described as the specifics being locale-dependent. This method takes the string that is "sub" and checks if it is equal to the substrings of the container string that are equal in length to the "sub". I did a test finding a case-insensitive match of a string. as it found that your characters were contained. Which would be the right way of comparing german words then? You can rate examples to help us improve the quality of examples. If you have to search an ASCII string in another ASCII string, such as a URL, you will find my solution to be better. That seems really close to Apache StringUtils method : @alain.janinm I fail to see the similarities. How to test if a Java String contains a case insensitive regex pattern. But if you have an array or a collection of thousands or hundreds of thousands of strings, things can get pretty slow. Can you improve your answer by explaining how your code resolves the problem? How to check whether a String contains a substring or not? The contains() method searches case sensitive char sequence. The only thing that seems "close" with. How to replace all occurrences of a string? If the argument is not case sensitive, it returns false. basically it is a method that takes two strings. Results (by calling the method 10 million times): Our method is 4x faster compared to lowercasing and using contains(), 10x faster compared to using regular expressions and also 3x faster even if the Pattern is pre-cached (and losing flexibility of checking for an arbitrary substring). In Java, how do I check if a string contains a substring (ignoring case)? The Java String compareTo() method compares two strings lexicographically (in the dictionary order), ignoring case differences. See my answer for the results (I also showed a faster solution): It would me more clear what was going on if we had better variable names: @user01 correctness comes before performance, and using toLowerCase will give potentially incorrect results (for example, when comparing certain Greek text containing the letter Sigma, which has two lowercase forms for the same uppercase form). We have seen above that the contains() method is case sensitive, however with a little trick, you can use this method for case insensitive checks. How to check if a string contains a specific sub string? Using regexp can be relatively slow. @kroiz, that depends where the String came from. I don't think this answer serves any purpose here. this method takes the string that is "sub" and check if it is equal to sub strings of the container string, that are equal in length to the "sub" . Example. Convert the string value into lower case letters using the toLowerCase() method, store it as subString.