There are many options to handle null values in a stream: 1. Removing repeating rows and columns from 2d array. Why is there a fake knife on the rack at the end of Knives Out (2019)? Stream API: create empty map with keys from enum, Why does Collectors.toMap require non null values. Why bad motor mounts cause the car to shake and vibrate at idle but not when you give it gas and increase the rpms? An empty optional is the main way to avoid the Null Pointer Exception when using the Optional API. Exception : If the element selected is null, NullPointerException is thrown. I don't understand this behaviour, maps can contain null pointers as value without any problems. Rectifying the code for the above NullPointerException using Optional Class: // Java program to avoid NullPointerException. Using Stream.ofNullable can ease the pain but it is just a nice-to-have feature in real-life application codes. Accessing or modifying a null object's field. How do I efficiently iterate over each entry in a Java Map? Null pointer Exceptions less than 1 minute read Handling Null pointer Exceptions Boolean Variables. Asking for help, clarification, or responding to other answers. implemented Holger's idea below, added a test method. Try to add .filter(s -> s != null) after map operation. Throws: 504), Mobile app infrastructure being decommissioned. Trick is equals() handles null so above is enough. While converting the list to map, the toMap() method internally uses merge() method from java.util.Map interface. Maybe merge is faster, but I have not tested. rev2022.11.7.43014. What are some tips to improve this product photo? Asking for help, clarification, or responding to other answers. Now, a couple NullPointerException with too many hard-to-read Lambda expressions, our codes will be hard to maintain. It doesnt allow the null key or values. null or contain By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Objects.nonNull () method returns true if the provided reference is non-null otherwise it returns false, and based on that Stream.filter () method will decide whether an element should filter or . To subscribe to this RSS feed, copy and paste this URL into your RSS reader. NullPointerException - if the element selected is null, Optional cannot differentiate between "present but null" and "not present". Not the answer you're looking for? Stream filter () in Java with examples. Codebase with a lot of Lamda expressions is large to analyze because of poor readability. How to help a student who has internalized mistakes? Null Pointer Exception when using filter and New operator with Corticon They make some point, but could stress the easy, safe, beautiful aspects of Java 8's Optional. Stream filter() in Java with examples - GeeksforGeeks Taking the length of null as if it were an array. If he wanted control of the company, why didn't Elon Musk buy 51% of Twitter shares instead of 100%? 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To do that, we can use a lambda expression: List<Customer> customersWithMoreThan100Points = customers .stream () .filter (c -> c.getPoints () > 100 ) .collect (Collectors.toList ()); We can also use a method reference . filter () is a intermediate Stream operation. null values. This makes the calling code look as clean as possible. public class NullPointerException extends RuntimeException. If employee is null then above method will throw NullPointerException. NullPointerException. Or use peek, which is used to alter the stream element for element. How to Solve java.lang.NullPointerException Error | Career Karma My profession is written "Unemployed" on my passport. Below are the possibilities: Entire list is null. QGIS - approach for automatically rotating layout window, Teleportation without loss of consciousness. Prefer primitive boolean types over Wrapper class to avoid creating objects & NPE. An awesome tip to avoid NPE is to return empty strings or empty collections rather than null. Making statements based on opinion; back them up with references or personal experience. which thereafter throws NPE, according to the spec of Optional.findFirst which reads: Also, to clarify the code control couldn't even reach the orElseGet part which anyway assumingly works over an Optional (either empty or with some value). Filter Null Values from a List with Java8 Lambda - DEV Community Is there any alternative way to eliminate CO2 buildup than by breathing or even an alternative to cellular respiration that don't produce CO2? Null Pointer Exception is a kind of run time exception that is thrown when the java program attempts to use the object reference that that contains the null value. null values. On the other hand, when we use Java Stream API we need to be aware that they are not bullet-proof and they can throw NullPointerException. does not support null keys or the value or remappingFunction is Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. Did Great Valley Products demonstrate full motion video on an Amiga streaming from a SCSI hard disk in 1990? How does DNS work when it comes to addresses after slash? I tried to solve the problem by coding a more native and straight forward approach. Tired of Null Pointer Exceptions? Consider Using Java SE 8's findFirst throws java.lang.NullPointerException - Stack Overflow Don't ignore exceptions, especially when you've caught the most generic out of them all. The empty Optional won't be processed any further. stream (). Resolve NullPointerException in Collectors.toMap Is this meat that I was told was brisket in Barcelona the same as U.S. brisket? 1. Stack Overflow for Teams is moving to its own domain! By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Collectors.toMap throws a NullPointerException if one of the values is null. Collector to map throwing NullPointerException when value is null in Java, why? Asking for help, clarification, or responding to other answers. The Stream interface has the following two methods in Java 8. If he wanted control of the company, why didn't Elon Musk buy 51% of Twitter shares instead of 100%? Null Pointer Exception in Java Programming - tutorialspoint.com Will Nondetection prevent an Alarm spell from triggering? if statements to check for If you want to avoid to check for every key, you can use something like, @Holger Yep, that's true. It happens because you return null in your map function. Is there any alternative way to eliminate CO2 buildup than by breathing or even an alternative to cellular respiration that don't produce CO2? Safer side in your code currently, you can filter-in only nonNull objects using filter as. Slight improvement to the duplicate message to mirror the one in Java 11, which also includes the duplicate's values: That works only if you are okay with modifying the data. Name for phenomenon in which attempting to solve a problem locally can seemingly fail because they absorb the problem from elsewhere? A common use case of the filter () method is processing collections. Why don't math grad schools in the U.S. use entrance exams? Some of the common reasons for NullPointerException in java programs are: Invoking a method on an object instance but at runtime the object is null. While converting the list to map, the toMap () method internally uses merge () method from java.util.Map interface. Splitting single huge .filter() operation to a few smaller ones makes your code much more readable and easier to maintain. Here, you have introduced possibility of NullPointerExceptions. 2D , NullPointerException. 1. So if you were able to put in k the value null, the map would look like it's behaving oddly. Java stream filter null pointer issue. Not the answer you're looking for? Java Doc Says: The merge() will throw NullPointerException the specified key is null and this map does not support null keys or the value or remappingFunction is null. Find the findFirst declaration from Java doc. Java 8 introduced several enhancements to Collection interface, like removeIf () method. Original implementation detects duplicate keys and throws an IllegalStatException, but this solution silently accepts the latest key. String [] a = new String [10]; The javadoc of toMap explains that toMap is based on Map.merge: @param mergeFunction a merge function, used to resolve collisions between values associated with the same key, as supplied to Map#merge(Object, Object, BiFunction)}, @throws NullPointerException if the specified key is null and this map Handling Java NullPointerException and Best Practices - HowToDoInJava NullPointerException when binding ConfigurationProperties (Spring Boot), IllegalStateException: "Duplicate key" for Collectors.toMap(), JPA query: java.lang.IllegalArgumentException: At least 1 parameter(s) provided but only 0 parameter(s) present in query, Getting java.lang.ClassCastException: class lambda.Student cannot be cast to class java.lang.Comparable while using FlatMap, How to overcome AWS V1 + V2 mismatch while using Java SQS SDK. Please provide the stacktrace, so it's easier to figure out where the NPE is coming from. map (str-> str . A Null Pointer Exception occurs using filters with Corticon 6.1.2 Downstream methods might expect null values rather than empty strings. Why doesn't this unzip all my files in a given directory? Try simplifying your stream calls to something like this: The good thing about streams is that every stream operation is lazy-evaluated, which means that all operations will be triggered in terminating .collect(Collectors.toList()) call. Never thought that null values in map would make such an impact on standard API, I'd rather consider it as a flaw. Find centralized, trusted content and collaborate around the technologies you use most. This is an intermediate operation. How can you prove that a certain file was downloaded from a certain website? With the Stream filtering operation, we create a new list with null values removed. It is not possible with the static methods of Collectors. Java 8 - Filter null values from a Stream - BeginnersBook EDIT: Codebase with a lot of Lamda expressions is large to analyze because of poor readability. Java SE 8 introduces a new class called java.util.Optional that can alleviate some of these problems. Do we ever see a hobbit use their natural ability to disappear? Accessing or modifying the field of a null object. Sorry to reopen an old question, but since it was edited recently saying that the "issue" still remains in Java 11, I felt like I wanted to point out this: gives you the null pointer exception because the map does not allow null as a value. public static void main (String [] args) {. Using Collection.removeIf () method. @Jagger yes, a definition of a supplier (the first argument) is a function that passes no parameters and returns a result, thus the lambda for your case would be. The nice short stream based solutions below could have a terrible performance. Syntax : Optional<T> findFirst () Where, Optional is a container object which may or may not contain a non-null value and T is the type of objects and the function returns an Optional describing the first element of this stream, or an empty Optional if the stream is empty. That means that for the common case that zero or one elements pass the filter, this operation will materialize the entire stream (whereas the find. This is how we can avoid a NullPointerException when using Optional. How does DNS work when it comes to addresses after slash? In this case we also make sure that every .getX() , .getY() and .getZ() does not return any null to avoid NullPointerException . Java Doc Says: The merge () will throw NullPointerException - the specified key is null and this map does not support . Null Checks to avoid NullPointerException Thanks for contributing an answer to Stack Overflow! Is there an industry-specific reason that many characters in martial arts anime announce the name of their attacks? Stringbuilder to 2D NullPointerException When the migration is complete, you will access your Teams at stackoverflowteams.com, and they will no longer appear in the left sidebar on stackoverflow.com. When the migration is complete, you will access your Teams at stackoverflowteams.com, and they will no longer appear in the left sidebar on stackoverflow.com. This makes sense because if you look in a map for the key k and it is not present, then the returned value is already null (see javadoc). Accepted answer does not compile because Map::putAll does not have a return value. @throws NullPointerException if the element selected is null Optional<T> findFirst (); Also, to clarify the code control couldn't even reach the orElseGet part which anyway assumingly works over an Optional (either empty or with some value). Making statements based on opinion; back them up with references or personal experience. Connect and share knowledge within a single location that is structured and easy to search. NullPointerException Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, @nullpointer I just log the exception in the, findFirst throws java.lang.NullPointerException, Going from engineer to entrepreneur takes more than just good code (Ep. In any of the cases your code is going to throw a NullPointerException. NullPointerException when working with Java Stream API in Java 9. I have this code below. Why does sending via a UdpClient cause subsequent receiving to fail? Stream filter (Predicate predicate) returns a stream consisting of the elements of this stream that match the given predicate. Java streams findAny() encounters null pointer exception after filter Thrown when an application attempts to use null in a case where an object is required. I already tried to check the stream entity for null, though it didn't work. The exception can be avoided by adding Null checks. Java Stream filter() with Examples - HowToDoInJava By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. What is the use of NTP server when devices have accurate time? It would make sense if a map did not allow null values, but it does. Empty Optional. Predicate is a functional interface. Protobuf client and server-side null handling with custom - Medium When I run this code a Null pointer exception occurs. Joking aside, the null reference is the source of many problems because it is often used to denote the absence of a value. Is there a good reason why values cannot be null for Collectors.toMap? Why was video, audio and picture compression the poorest when storage space was the costliest? As easy as that! These include: Calling the instance method of a null object. import java.util.Optional; public class Example {. Java Stream findFirst() - concretepage In other words, separates a mapping with null-value from no-mapping. Rust Programming Language For Beginners Tutorial, Headstart Framework: a Java and Spring Boot-based Framework, Spring Boot How to use @Conditional in your own codes. When we pass Accessing index or modifying value of an index of an array that is null. Avoid Null and NullPointerException Altogether - DZone Core Java bootcamp program with Hands on practice. I had to specify the type parameters in order to compile, that way: This might be quite slow on a large input. Stack Overflow for Teams is moving to its own domain! Where to find hikes accessible in November and reachable by public transport from Denver? By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Difference between findAny() and findFirst() in Java 8, IntStream.boxed() vs for loop | Performance, Java 8 - stream - method in filter has unhandled exception, try catch is expecting return statement, Filter out null values in Java 8 stream filter expression so exception is not thrown, A planet you can take off from, but never land back. JAVA Querying the list of data using Stream filter,null pointer exception Optional from null or non-null value You can create Optional from null or non null value using static factory method "ofNullable" Optional<Employee> optCar = Optional.ofNullable (employee); Getting value from Optional In the previous tutorials, we discussed how to convert a list to map in Java 8. In Optional 's flow, a null will be transformed into an empty Optional. Best Java code snippets using java.util.stream. Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. Did find rhyme with joined in the 18th century? These can be: Invoking a method from a null object. If you don't want this, look at the link in the comment. rev2022.11.7.43014. If the value is a String, then this might work: Counting from the 21st century forward, what is the last place on Earth that will get to experience a total solar eclipse? Why does findFirst() throw a NullPointerException if the first element it finds is null? When the codes process that To remove null values from a list, we can pass Objects.nonNull () to removeIf () method: There are many other ways to remove null values from a . Name for phenomenon in which attempting to solve a problem locally can seemingly fail because they absorb the problem from elsewhere? Stream.filter (Showing top 20 results out of 71,244) answerList .stream () .collect (Collectors.toMap (Answer::getId, Answer::getAnswer)); gives you the null pointer exception because the map does not allow null as a value. //Check accountId for null and not being empty and follow account# schema Optional<Account . Is it enough to verify the hash to ensure file is virus free? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, @kajacx But the default implementation is. Well, just use it instead of toMap() like the tests show. Use filter to filter all NULL values, and in the Javascript code check if the server didn't send any answer for this id means that he didn't reply to it. null reference element. Even if the object is null in this case, it will not give an exception and will print ' null ' to the output stream. Position where neither player can force an *exact* outcome. The Optional class has a filter () method, which is just like the same method in the Stream API. Stream.of (Showing top 20 results out of 23,589) For example, using a method on a null reference. Light bulb as limit, to what is current limited to? System.out.println (value.toString ()); In the above snippet, we don't check if the key . stream.filter(Objects::nonNull).forEach(this::consume); // XXX this causes null-warnings because the filter-call does not change the nullness of the stream parameter I have a solution using flatMap(), but it would be much nicer if the filter method could just return @Nonnull String when called using the Objects::nonNull function. Personally, with the given circumstances, I would go with non-stream solution, or forEach() if the input is parallel. Also, is there a nice Java 8 way of fixing this, or should I revert to plain old for loop? Likely the #1 most common cleanup step is to remove nulls from a Collection. Avoid NullPointerException with Stream.ofNullable in Java 9 The filter () argument should be stateless predicate which is applied to each element in the stream to determine if it should be included or not. Light bulb as limit, to what is current limited to? Java 8 Lambda function that throws exception? The null pointer exception can be thrown in the following scenarios. Got comments or suggestions? Processing only finishes early when a second element is encountered. Recipe 20: Use the filter () method to filter a wrapped value. 503), Fighting to balance identity and anonymity on the web(3) (Ep. Remove null values from a List in Java 8 and above The problem with these methods is that they throw exceptions when they argument are Instead use String.valueOf (object). . Although the Java Stream API is powerful, it is generally to keep its usage to a minimum. (clarification of a documentary). Java 8 Example: Filter null values from a stream We can use lambda expression str -> str!=null inside stream filter () to filter out null values from a stream. // if any object in a list is NULL list. Find centralized, trusted content and collaborate around the technologies you use most. Especially since. What is this political cartoon by Bob Moran titled "Amnesty" about? null to a non-null-safe overloaded method that takes an array, the codes throw a It returns a Stream consisting of the elements of the given stream that match the given predicate. 504), Mobile app infrastructure being decommissioned, Java 8 Convert Map to Map. When the migration is complete, you will access your Teams at stackoverflowteams.com, and they will no longer appear in the left sidebar on stackoverflow.com. but it is not really simple than the old way: I wrote a Collector which, unlike the default java one, does not crash when you have null values: Just replace your Collectors.toMap() call to a call to this function and it'll fix the problem. Making statements based on opinion; back them up with references or personal experience. // Create a String of size 10. Consider the following codes. NullPointerException (Java Platform SE 7 ) - Oracle Taking the length of null, as if it were an array. Consider a scenario where you build a query model from a request where the fields that are supposed to be null are empty strings, (you should not jump to a server-side solution where you replace . Is it possible to make a high-side PNP switch circuit active-low with less than 3 BJTs? a NullPointerException . These operations are always lazy i.e, executing an intermediate operation such as filter () does not actually perform any filtering, but instead . Can an adult sue someone who violated them as a child? I think it's as direct as possible: And how do you use it? Although the Java Stream API is powerful, it is generally to keep its usage to a minimum. In the first case it returns a stream with the null element in it which throws NullPointerException, in the second case it returns an empty stream which works fine. 504), Mobile app infrastructure being decommissioned, NullPointerException in Java with no StackTrace, Hibernate - A collection with cascade=all-delete-orphan was no longer referenced by the owning entity instance, Getting the IP address of the current machine using Java, Filter Java Stream to 1 and only 1 element, Convert Iterable to Stream using Java 8 JDK, Java streams findAny() encounters null pointer exception after filter() operation filters out everything, way to find the List of all ids in a list of entities from inner object with java 8, Handling unprepared students as a Teaching Assistant, Space - falling faster than light? What is the difference between an "odor-free" bully stick vs a "regular" bully stick? Avoid NullPointerException using Java 8 Optional - amitph ( 2019 ) code currently, you agree to our terms of service privacy. Via a UdpClient cause subsequent receiving to fail cases your code much more readable and easier to figure where... Does not support motion video on an Amiga streaming from a null object #... Boolean Variables there a nice Java 8 this product photo order to compile, that way this! An empty Optional many problems because it is often used to denote the absence of a value expect values! Element for element all my files in a given directory this stream that match the given circumstances, i rather... Above is enough 23,589 ) for example, using a method from a null reference where neither player force. Occurs using filters with Corticon 6.1.2 Downstream methods might expect null values in a map. Car to shake and vibrate at idle but not when you give it gas and increase the rpms does (. Entire list is null to put in k the value null, NullPointerException is thrown be any... To check the stream element for element why did n't work if has! Is the use of NTP server when devices have accurate time do we ever see a hobbit their! Solve the problem from elsewhere 18th century because of poor readability ) like the show... This political cartoon by Bob Moran titled `` Amnesty '' about many characters martial... Present '' to map throwing NullPointerException when value is null then above method will throw NullPointerException solutions below have. Can ease the pain but it is not possible with the given.. Usage to a few smaller ones makes your code is going to throw NullPointerException... Than by breathing or even an alternative to cellular respiration that do n't produce CO2 silently accepts latest! Huge.filter ( s - > s! = null ) after map operation it n't... Over each entry in a list is null and not being empty and follow account # schema Optional & ;... - > s! = null ) after map operation by coding a more native and straight forward.! To check the stream API in Java 8 way of fixing this, look at the end Knives... Values, but i have not tested our terms of service, privacy policy and policy..., a null object match the given predicate much more readable and easier to maintain the. Is used to denote the absence of a null object be thrown in the U.S. entrance... Stream element for element: 504 ), Mobile app infrastructure being decommissioned {... Infrastructure being decommissioned Fighting to balance identity and anonymity on the web ( 3 ) Ep. Side in your code currently, you can filter-in only nonNull objects using as... Is it enough to verify the hash to ensure file is virus free the tests.! Than 3 BJTs they absorb the problem by coding a more native and straight forward approach as a.... The technologies you use most consider it as a child into an empty won... Processed any further - > s! = null ) after map operation full motion video on an streaming. Uses merge ( ) method, which is just like the same in... Is enough results out of 23,589 ) for example, using a method from java.util.Map.! `` present but null '' and `` not present '' forward approach 'd rather it! You agree to our terms of service, privacy policy and cookie policy on a will! Phenomenon in which attempting to solve a problem locally can seemingly fail because they absorb the problem by a. Each entry in a list is null, the map would make such an impact standard... A hobbit use their natural ability to disappear because it is not possible with the predicate... Pass accessing index or modifying the field of a null will be transformed into an Optional. Exceptions less than 3 BJTs stream consisting of the company, why does sending via a UdpClient subsequent. > < /a > Collectors.toMap throws a NullPointerException if the key it did n't Elon Musk 51. ; in the stream API poorest when storage space was the costliest moving! Code much more readable and easier to figure out where the NPE coming. ) like the tests show > < /a > Collectors.toMap throws a NullPointerException if the element is! Rss feed, copy and paste this URL into your RSS reader prove. To stack Overflow for Teams is moving to its own domain values is null, it. A child above snippet, we don & # x27 ; s field specify type! To its own domain several enhancements to Collection interface, like removeIf ( ) method to a! Share knowledge within a single location that is null Products demonstrate full video... A hobbit use their natural ability to disappear PNP switch circuit active-low with than... Arts anime announce the name of their attacks to return empty strings or collections. Ones makes your code currently, you agree to our terms of,. Can alleviate some of these problems demonstrate full motion video on an Amiga streaming a! On an Amiga streaming from a Collection in Java 9 selected is null like it 's easier to figure where. Null in your map function our codes will be transformed into an empty Optional improve this photo... Look like it 's behaving oddly than empty strings or empty collections rather empty... < /a > Collectors.toMap throws a NullPointerException easy to search peek, which is to. When it comes to addresses after slash a fake knife on the rack at the end of Knives out 2019... Optional is the source of many problems because it is generally to keep usage. Of toMap ( ) method internally uses merge ( ) method from java.util.Map interface index an. /A > Collectors.toMap throws a NullPointerException when working with Java stream API is powerful, is... The value null, though it did n't Elon Musk buy 51 % of Twitter shares instead of (. By Bob Moran titled `` Amnesty '' about approach for automatically rotating layout window, Teleportation without loss consciousness! To verify the hash to ensure file is virus free of a null reference is the source of problems! Coding a more native and straight forward approach as value without any problems rotating... Exception: if the first element it finds is null, Optional can be! If the element selected is null and not being empty and follow account # Optional... Lamda expressions is large to analyze because of poor readability only nonNull objects using filter as ( Ep uses... Elon Musk buy 51 % of Twitter shares instead of 100 %: //www.amitph.com/avoid-nullpointerexception-using-java-8-optional/ '' > < /a > throws... Just use it map operation how can you prove that a certain website analyze because of poor readability [! Doc Says: the merge ( ) throw a NullPointerException the possibilities: Entire list is?. A nice-to-have feature in real-life application codes to avoid the null Pointer exception occurs using filters with 6.1.2. A href= '' https: //www.onlinetutorialspoint.com/java8/resolve-nullpointerexception-in-collectors-tomap.html '' > < /a > Collectors.toMap a. List is null, NullPointerException is thrown < /a > Collectors.toMap throws a NullPointerException class. With null values in map would make such an impact on standard,. Is large to analyze because of poor readability: // Java program to avoid objects. Aside, the toMap ( ) method internally uses merge ( ) throw a.... And this map does not have a return value it would make such an impact on standard,... 1 most common cleanup step is to remove nulls from a null object handles null so above is.. Null object breathing or even an alternative to cellular respiration that do n't want this, look the... Stream element for element loss of consciousness i had to specify the type parameters in order compile! A given directory - the specified key is null in k the value null, NullPointerException is thrown fail they! To plain old for loop handle null values in a Java map Amnesty '' about with the methods. Terms of service, privacy policy and cookie policy //www.onlinetutorialspoint.com/java8/resolve-nullpointerexception-in-collectors-tomap.html '' > avoid NullPointerException Thanks contributing. Expect null values vibrate at idle but not when you give it gas increase. He wanted control of the values is null, the toMap ( ) method to filter a value. That do n't math grad schools in the stream interface has the following.... Element for element minute read Handling null Pointer Exceptions less than 1 minute read Handling null Pointer exception when Optional. S - > s! = null ) after map operation this might be quite slow a. Should i revert to plain old for loop contributing an answer to stack stream filter null pointer exception. A fake knife on the rack at the link in the U.S. use entrance?. For Teams is moving to its own domain to map, the map would look like 's. Example, using a method from java.util.Map interface titled `` Amnesty '' about a value to., privacy policy and cookie policy well, just use it by public transport from Denver value.toString ( method. Java stream API: create empty map with keys from enum, why did n't work create... Sense if a map did not allow null values rather than empty strings or empty rather. Also, is there a nice Java 8 introduced several enhancements to Collection interface, like (! Out where the NPE is to return empty strings or empty collections rather than.... Optional won & # x27 ; t be processed any further but not when you give it gas increase.
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