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I downloaded the lambdasinaction code example, but there are some errors.
For example：
The method flatMapping(( dish) -> {}, toSet()) is undefined for the type Grouping in chap3 package, The code: private static Map<Dish.Type, Set<String>> groupDishTagsByType() { return menu.stream().collect(groupingBy(Dish::getType, flatMapping(dish -> dishTags.get( dish.getName() ).stream(), toSet()))); }

And The method filtering(( dish) -> {}, toList()) is undefined for the type Grouping in chap3 package, The code private static Map<Dish.Type, List<Dish>> groupCaloricDishesByType() { return menu.stream().collect(groupingBy(Dish::getType, filtering(dish -> dish.getCalories() > 500, toList()))); }

When I practice， encountered a lot of errors . The method toList() 、groupingBy、comparing()....is undefined for the type TestStream.
By the way, i used jdk 1.8.0.171，Is it because the JDK version is too low ？

and update the README.

Can you run?I can not successfully run the OptionalMain.java.What went wrong,Here
public String getCarInsuranceName(Optional<Person> person) { return person.flatMap(Person::getCar) .flatMap(Car::getInsurance) .map(Insurance::getName) .orElse("Unknown"); }

I got NullPointException.The Exception:

Not able to compile the code as its throwing lots of ERROR.

For Chapter6, I am getting below error:

The method flatMapping((<no type> dish) -> {}, toSet()) is undefined for the type Grouping

I have installed jdk9

java version "9"
Java(TM) SE Runtime Environment (build 9+181)
Java HotSpot(TM) 64-Bit Server VM (build 9+181, mixed mode)

my idea environment jdk is 9

I think that replace "lambdasinaction/chap3/data.txt" with ExecuteAround.class.getResource("/lambdasinaction/chap3/data.txt").getPath() should solve the problem.

int your chap6 Group.java hava a bug , filtering method not in java8 sdk .

Change the 'Make sure to have JDK8 installed' to 'Make sure to have JDK9 installed' to avoid the build failure.

This field can be define as a private

private static final long THRESHOLD = 10_000;

class: lambdasinaction.chap10.OperationsWithOptional
line 15 and line 18
The method or(() -> {}) is undefined for the type Optional

class: lambdasinaction.chap10.OptionalMain
line 21
The method flatMap(Function<? super Optional,? extends Stream<? extends R>>) in the type Stream<Optional> is not applicable for the arguments (Optional::stream)

class: lambdasinaction.chap6.Grouping
line 36
The method flatMapping(( dish) -> {}, toSet()) is undefined for the type Grouping

line 41
The method filtering(( dish) -> {}, toList()) is undefined for the type Grouping

class: lambdasinaction.chap6.PartitionPrimeNumbers
line 36
The method takeWhile(( i) -> {}) is undefined for the type Stream

Similar problem as described in issue #5. The get in Files.lines(Paths.get("lambdasinaction/chap5/data.txt"), ... will fail. Need to resolve the file path using getResource like in issue #5 for the code to work.

I would love to use it for testing Java 8 support for JavaParser (https://github.com/matozoid/javaparser)

String[] stringArray = {"A,B","B,A","C,D","C,B","A,V"};
stringArray.stream() ------>> Cannot invoke stream() on the array type String[]

is it not good to have streaming on Array as well? :)

public static boolean isPrime(List<Integer> primes, Integer candidate) {
    double candidateRoot = Math.sqrt((double) candidate);
    //return takeWhile(primes, i -> i <= candidateRoot).stream().noneMatch(i -> candidate % i == 0);
    return primes.stream().**takeWhile**(i -> i <= candidateRoot).noneMatch(i -> candidate % i == 0);
}

-> the function takeWhile is invalid or doesn't exists

I used openjdk 10 to run it. Openjdk 8 can't compile and run

BestPriceFinder.java

public Stream<CompletableFuture> findPricesStream(String product) {
return shops.stream()
.map(shop -> CompletableFuture.supplyAsync(() -> shop.getPrice(product), executor))
.map(future -> future.thenApply(Quote::parse))
.map(future -> future.thenCompose(quote -> CompletableFuture.supplyAsync(() -> Discount.applyDiscount(quote), executor)));
}

private static Map<Dish.Type, Set> groupDishTagsByType() {
return menu.stream().collect(groupingBy(Dish::getType, flatMapping(dish -> dishTags.get( dish.getName() ).stream(), toSet())));
}
-> flatMapping shown as invalid and don't compile the class

private static Map<Dish.Type, List<Dish>> groupCaloricDishesByType() {

// return menu.stream().filter(dish -> dish.getCalories() > 500).collect(groupingBy(Dish::getType));
return menu.stream().collect(groupingBy(Dish::getType, filtering(dish -> dish.getCalories() > 500, toList())));
}
-> filtering shown as invalid and don't compile the class

I have the first edition of the book. I just cloned the repo and tried to build with jdk8 and it's broken all over the place. Could you create a tag or branch for the Java 8 version?

I try to compile sources on Mac with Java 1.8.0_91

I get:
chojnasm-ml:Java8InAction chojnasm$ mvn compile
[INFO] Scanning for projects...
[WARNING]
[WARNING] Some problems were encountered while building the effective model for manning:lambdasinaction:jar:1.0
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-shade-plugin is missing. @ line 44, column 15
[WARNING]
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING]
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
[WARNING]
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building lambdasinaction 1.0
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ lambdasinaction ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 2 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ lambdasinaction ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 100 source files to /Users/chojnasm/Downloads/Java8InAction/target/classes
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.558 s
[INFO] Finished at: 2017-02-27T14:27:45+00:00
[INFO] Final Memory: 9M/309M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project lambdasinaction: Fatal error compiling: invalid target release: 1.9 -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException