As part of solution choose any of the following. Break method call and argument pass in two calls – Integer i = getInteger(); print(i); Or Call print method with Typed argument – print(Main.<Integer>getInteger()); I hope it will help. 10 solved Java 8 generic type conversion fails where as it was passing with java 7
It seems that a raw list/array needs to be created including fields from Employee and Address (assuming appropriate getters exist in these classes): List<List<Object>> flattened = list.stream() .flatMap(emp -> emp.getAddresses().stream() .map(addr -> Arrays.asList( emp.getName(), emp.getId(), addr.getAddress(), addr.getPostalCode() )) ) .collect(Collectors.toList()); flattened.forEach(System.out::println); // should print desired result solved Flattening nested list in java [closed]
Use LocalDateTime with its toString(). String s = LocalDateTime.now().toString(); // ISO standard representation // LocalDateTime to old Date: Date date = Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant()); // Old Date holding time to LocalDateTime: LocalDateTime localDateTime = LocalDateTime.ofInstant(date.toInstant(), ZoneId.systemDefault()); Of cause with an SQL PreparedStatement, you could simply call setDate without the detour via String. solved How to format my … Read more
it should be a supplier: .orElseThrow(() -> new UserNotFoundException(“User doesnt exist in system”)); 0 solved Error while throwing User defined exception using orElseThrow in java 8 [duplicate]
Assuming you want a Map<User.userId, List<UserData.customerId>> you can use this: Map<Long, List<Long>> result = users.stream() .collect(Collectors.toMap( User::getUserId, u -> u.getUserData().stream() .map(UserData::getCustomerId) .collect(Collectors.toList()) )); 3 solved Java 8 – collecting into a map from a list of objects with nested list
It will call (1) because the method resolution algorithm gives priority to methods that do not use varargs. To force it to use (2) you can pass an array or cast the first parameter to Object: myMethod(new Object[] { “name”, new MyClass() }); //or myMethod((Object) “name”, new MyClass()); 1 solved Method Overloading – Java
nextGaussian() can return any value that can represented by a double data type. Gaussian distribution approaches but never reaches 0 on either side. So it’s theoretically possible to get a value of Double.MAX_VALUE, but very unlikely. Gaussian distribution looks like this: (http://hyperphysics.phy-astr.gsu.edu/hbase/Math/gaufcn.html) The distribution stretches to positive and negative infinity, so there is theoretically no … Read more
Does Java 8 specification allow to use interface reference type variable on objects that don’t use the implements keyword explicitly? [closed] solved Does Java 8 specification allow to use interface reference type variable on objects that don’t use the implements keyword explicitly? [closed]
If you want to create a function which adds 1 to its input, the method to create that function doesn’t need an parameters… but then you need to call that function in order to execute it. I suspect you wanted: import java.util.function.Function; public class LambdaExpression { public static Function<Integer, Integer> create() { Function<Integer, Integer> f … Read more
What about this? Files.list(Paths.get(“somedir”)).sorted().forEach(System.out::println); 1 solved List of files in directory with new File API
The LocalDate class has isAfter(LocalDate other) isBefore(LocalDate other) isEqual(LocalDate other) methods for comparisons with other dates. Here is an example: LocalDate today = LocalDate.now(); LocalDate tomorrow = LocalDate.now().plusDays(1); LocalDate yesterday = LocalDate.now().minusDays(1); if(today.isAfter(yesterday) && today.isBefore(tomorrow)) System.out.println(“Today is… today!”); solved Date between other Dates java.time [duplicate]
Make sure that you correctly selected the JDK. In IntelliJ you should go to: File -> Project Structure… project settings tab, and make sure the project SDK points to the location of your java 8 JDK, (something like: C:\Program Files\java\jdk1.8.0_45) And, of course, make sure the project language level is set to 8 – Lambdas, … Read more
Following snippet might be a point to start with. URL url = new URL(“http://example.com/acct/StatsClientListService” + “?clientType=AllClient&something=interesting”); Stream.of(url.getQuery().split(“&”)) .collect(Collectors.toMap( s -> s.replaceFirst(“^(.*)=.*”, “$1”), s -> s.replaceFirst(“^.*=(.*)”, “$1”))) .forEach((k, v) -> System.out.printf(“param: %s value: %s%n”, k, v) ); output param: clientType value: AllClient param: something value: interesting edit If the URL string contain only the path and … Read more
Just use comparator, an example of sorting by firstName then by lastName list.forEach(l -> l.sort(Comparator.comparing(CsvEntity::getFirstName) .thenComparing(CsvEntity::getLastName))); Of course you have to have getters for your fields to use method reference solved how sort in java8 list of lists of object by multiple properties [duplicate]
tl;dr OffsetDateTime .parse( “Wed, 20 Feb 2019 07:14:06 +0100” , DateTimeFormatter.RFC_1123_DATE_TIME ) .toString() 2019-02-20T07:14:06+01:00 Details Your problem has nothing to do with Java 8 versus Java 17. Tip: Before blaming software that is formally specified, is thoroughly tested by enormous test suites, and is used by millions of programmers daily, suspect your own code first. … Read more