diff --git a/account-analytics/src/main/java/com.bobocode/AccountAnalytics.java b/account-analytics/src/main/java/com.bobocode/AccountAnalytics.java index 8c825fb..0b7bdff 100644 --- a/account-analytics/src/main/java/com.bobocode/AccountAnalytics.java +++ b/account-analytics/src/main/java/com.bobocode/AccountAnalytics.java @@ -2,10 +2,17 @@ import com.bobocode.exception.EntityNotFoundException; import com.bobocode.model.Account; +import com.bobocode.model.Sex; import java.math.BigDecimal; import java.time.Month; import java.util.*; +import java.util.function.Function; +import java.util.stream.Stream; + +import static java.util.Comparator.comparing; +import static java.util.function.Function.identity; +import static java.util.stream.Collectors.*; import static java.util.stream.Collectors.mapping; import static java.util.stream.Collectors.toMap; @@ -30,7 +37,8 @@ private AccountAnalytics(Collection accounts) { * @return account with max balance wrapped with optional */ public Optional findRichestPerson() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .max(comparing(Account::getBalance)); } /** @@ -40,7 +48,9 @@ public Optional findRichestPerson() { * @return a list of accounts */ public List findAccountsByBirthdayMonth(Month birthdayMonth) { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .filter(a -> a.getBirthday().getMonth().equals(birthdayMonth)) + .collect(toList()); } /** @@ -50,7 +60,8 @@ public List findAccountsByBirthdayMonth(Month birthdayMonth) { * @return a map where key is true or false, and value is list of male, and female accounts */ public Map> partitionMaleAccounts() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .collect(partitioningBy(a -> a.getSex().equals(Sex.MALE))); } /** @@ -60,7 +71,8 @@ public Map> partitionMaleAccounts() { * @return a map where key is an email domain and value is a list of all account with such email */ public Map> groupAccountsByEmailDomain() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .collect(groupingBy(a -> a.getEmail().split("@")[1])); } /** @@ -69,7 +81,9 @@ public Map> groupAccountsByEmailDomain() { * @return total number of letters of first and last names of all accounts */ public int getNumOfLettersInFirstAndLastNames() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .mapToInt(a -> a.getFirstName().length() + a.getLastName().length()) + .sum(); } /** @@ -78,7 +92,9 @@ public int getNumOfLettersInFirstAndLastNames() { * @return total balance of all accounts */ public BigDecimal calculateTotalBalance() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .map(Account::getBalance) + .reduce(BigDecimal.ZERO, BigDecimal::add); } /** @@ -87,7 +103,10 @@ public BigDecimal calculateTotalBalance() { * @return list of accounts sorted by first and last names */ public List sortByFirstAndLastNames() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .sorted(comparing(Account::getFirstName) + .thenComparing(Account::getLastName)) + .collect(toList()); } /** @@ -97,7 +116,9 @@ public List sortByFirstAndLastNames() { * @return true if there is an account that has an email with provided domain */ public boolean containsAccountWithEmailDomain(String emailDomain) { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .map(Account::getEmail) + .anyMatch(email -> email.split("@")[1].equals(emailDomain)); } /** @@ -108,7 +129,11 @@ public boolean containsAccountWithEmailDomain(String emailDomain) { * @return account balance */ public BigDecimal getBalanceByEmail(String email) { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .filter(account -> account.getEmail().equals(email)) + .findFirst() + .map(Account::getBalance) + .orElseThrow(() -> new EntityNotFoundException(String.format("Cannot find Account by email=%s", email))); } /** @@ -117,7 +142,8 @@ public BigDecimal getBalanceByEmail(String email) { * @return map of accounts by its ids */ public Map collectAccountsById() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .collect(toMap(Account::getId, identity())); } /** @@ -128,7 +154,9 @@ public Map collectAccountsById() { * @return map of account by its ids the were created in a particular year */ public Map collectBalancesByIdForAccountsCreatedOn(int year) { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .filter(account -> account.getCreationDate().getYear() == year) + .collect(toMap(Account::getEmail, Account::getBalance)); } /** @@ -138,7 +166,8 @@ public Map collectBalancesByIdForAccountsCreatedOn(int year) * @return a map where key is a last name and value is a set of first names */ public Map> groupFirstNamesByLastNames() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .collect(groupingBy(Account::getLastName, mapping(Account::getFirstName, toSet()))); } /** @@ -148,7 +177,9 @@ public Map> groupFirstNamesByLastNames() { * @return a map where a key is a birthday month and value is comma-separated first names */ public Map groupCommaSeparatedFirstNamesByBirthdayMonth() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .collect(groupingBy(a -> a.getBirthday().getMonth(), + mapping(Account::getFirstName, joining(", ")))); } /** @@ -158,7 +189,10 @@ public Map groupCommaSeparatedFirstNamesByBirthdayMonth() { * @return a map where key is a creation month and value is total balance of all accounts created in that month */ public Map groupTotalBalanceByCreationMonth() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .collect(groupingBy(a -> a.getCreationDate().getMonth(), + mapping(Account::getBalance, + reducing(BigDecimal.ZERO, BigDecimal::add)))); } /** @@ -168,7 +202,11 @@ public Map groupTotalBalanceByCreationMonth() { * @return a map where key is a letter and value is its count in all first names */ public Map getCharacterFrequencyInFirstNames() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .map(Account::getFirstName) + .flatMapToInt(String::chars) + .mapToObj(c -> (char) c) + .collect(groupingBy(identity(), counting())); } /** @@ -178,7 +216,12 @@ public Map getCharacterFrequencyInFirstNames() { * @return a map where key is a letter and value is its count ignoring case in all first and last names */ public Map getCharacterFrequencyIgnoreCaseInFirstAndLastNames() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return accounts.stream() + .flatMap(a -> Stream.of(a.getFirstName(), a.getLastName())) + .map(String::toLowerCase) + .flatMapToInt(String::chars) + .mapToObj(c -> (char) c) + .collect(groupingBy(identity(), counting())); } } diff --git a/crazy-lambdas/src/main/java/com/bobocode/CrazyLambdas.java b/crazy-lambdas/src/main/java/com/bobocode/CrazyLambdas.java index 966d72c..6a329f1 100644 --- a/crazy-lambdas/src/main/java/com/bobocode/CrazyLambdas.java +++ b/crazy-lambdas/src/main/java/com/bobocode/CrazyLambdas.java @@ -1,8 +1,8 @@ package com.bobocode; import java.math.BigDecimal; +import java.util.concurrent.ThreadLocalRandom; import java.util.Map; -import java.util.TreeMap; import java.util.function.*; public class CrazyLambdas { @@ -13,7 +13,7 @@ public class CrazyLambdas { * @return a string supplier */ public static Supplier helloSupplier() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return () -> "Hello"; } /** @@ -22,7 +22,7 @@ public static Supplier helloSupplier() { * @return a string predicate */ public static Predicate isEmptyPredicate() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return String::isEmpty; } /** @@ -32,7 +32,7 @@ public static Predicate isEmptyPredicate() { * @return function that repeats Strings */ public static BiFunction stringMultiplier() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return String::repeat; } /** @@ -42,7 +42,7 @@ public static BiFunction stringMultiplier() { * @return function that converts adds dollar sign */ public static Function toDollarStringFunction() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return bigDecimal -> "$" + bigDecimal; } /** @@ -54,7 +54,7 @@ public static Function toDollarStringFunction() { * @return a string predicate */ public static Predicate lengthInRangePredicate(int min, int max) { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return str -> str.length() >= min && str.length() < max; } /** @@ -63,7 +63,7 @@ public static Predicate lengthInRangePredicate(int min, int max) { * @return int supplier */ public static IntSupplier randomIntSupplier() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return () -> ThreadLocalRandom.current().nextInt(); } @@ -73,7 +73,7 @@ public static IntSupplier randomIntSupplier() { * @return int operation */ public static IntUnaryOperator boundedRandomIntSupplier() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return bound -> ThreadLocalRandom.current().nextInt(bound); } /** @@ -82,7 +82,7 @@ public static IntUnaryOperator boundedRandomIntSupplier() { * @return square operation */ public static IntUnaryOperator intSquareOperation() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return a -> a * a; } /** @@ -91,7 +91,7 @@ public static IntUnaryOperator intSquareOperation() { * @return binary sum operation */ public static LongBinaryOperator longSumOperation() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return (a, b) -> a + b; } /** @@ -100,7 +100,7 @@ public static LongBinaryOperator longSumOperation() { * @return string to int converter */ public static ToIntFunction stringToIntConverter() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return Integer::parseInt; } /** @@ -111,7 +111,7 @@ public static ToIntFunction stringToIntConverter() { * @return a function supplier */ public static Supplier nMultiplyFunctionSupplier(int n) { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return () -> a -> n * a; } /** @@ -120,7 +120,7 @@ public static Supplier nMultiplyFunctionSupplier(int n) { * @return function that composes functions with trim() function */ public static UnaryOperator> composeWithTrimFunction() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return stringFunction -> stringFunction.compose(String::trim); } /** @@ -131,7 +131,11 @@ public static UnaryOperator> composeWithTrimFunction() * @return a thread supplier */ public static Supplier runningThreadSupplier(Runnable runnable) { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return () -> { + Thread thread = new Thread(runnable); + thread.start(); + return thread; + }; } /** @@ -140,7 +144,7 @@ public static Supplier runningThreadSupplier(Runnable runnable) { * @return a runnable consumer */ public static Consumer newThreadRunnableConsumer() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return runnable -> new Thread(runnable).start(); } /** @@ -150,7 +154,11 @@ public static Consumer newThreadRunnableConsumer() { * @return a function that transforms runnable into a thread supplier */ public static Function> runnableToThreadSupplierFunction() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return runnable -> () -> { + Thread thread = new Thread(runnable); + thread.start(); + return thread; + }; } /** @@ -163,7 +171,7 @@ public static Function> runnableToThreadSupplierFunct * @return a binary function that receiver predicate and function and compose them to create a new function */ public static BiFunction functionToConditionalFunction() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return (intOperation, intPredicate) -> a -> intPredicate.test(a) ? intOperation.applyAsInt(a) : a; } /** @@ -174,7 +182,7 @@ public static BiFunction funct * @return a high-order function that fetches a function from a function map by a given name or returns identity() */ public static BiFunction, String, IntUnaryOperator> functionLoader() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return (functionMap, functionName) -> functionMap.getOrDefault(functionName, IntUnaryOperator.identity()); } /** @@ -183,7 +191,8 @@ public static BiFunction, String, IntUnaryOperator * @return a supplier instance */ public static Supplier>> trickyWellDoneSupplier() { - throw new UnsupportedOperationException("It's your job to implement this method"); // todo + return () -> () -> () -> "WELL DONE!"; } } + diff --git a/math-functions/src/main/java/com.bobocode/Functions.java b/math-functions/src/main/java/com.bobocode/Functions.java index 80ebc20..f983960 100644 --- a/math-functions/src/main/java/com.bobocode/Functions.java +++ b/math-functions/src/main/java/com.bobocode/Functions.java @@ -1,5 +1,7 @@ package com.bobocode; +import static java.lang.Math.abs; + public class Functions { /** * A static factory method that creates an integer function map with basic functions: @@ -14,7 +16,11 @@ public class Functions { public static FunctionMap intFunctionMap() { FunctionMap intFunctionMap = new FunctionMap<>(); - // todo: add simple functions to the function map (abs, sng, increment, decrement, square) + intFunctionMap.addFunction("square", n -> n * n); + intFunctionMap.addFunction("abs", Math::abs); + intFunctionMap.addFunction("increment", n -> n + 1); + intFunctionMap.addFunction("decrement", n -> n - 1); + intFunctionMap.addFunction("sgn", n -> (n != 0) ? n / abs(n) : 0); return intFunctionMap; } diff --git a/sum-of-squares/src/main/java/com/bobocode/SumOfSquares.java b/sum-of-squares/src/main/java/com/bobocode/SumOfSquares.java index fc0dfde..56736c2 100644 --- a/sum-of-squares/src/main/java/com/bobocode/SumOfSquares.java +++ b/sum-of-squares/src/main/java/com/bobocode/SumOfSquares.java @@ -3,6 +3,8 @@ import com.bobocode.exception.InvalidRangeException; +import java.util.stream.IntStream; + /** * This class allow to calculate a sum of squares of integer number in a certain range. It was implemented using @@ -17,7 +19,7 @@ public static void main(String[] args) { * This method calculates the sum of squares of integer in the range * * @param startInclusive first element in range - * @param endInclusive last element in range + * @param endInclusive last element in range * @return the sum of squares of each element in the range */ static int calculateSumOfSquaresInRange(int startInclusive, int endInclusive) { @@ -25,11 +27,8 @@ static int calculateSumOfSquaresInRange(int startInclusive, int endInclusive) { throw new InvalidRangeException(); } - // todo: refactor using functional approach - int sumOfSquares = 0; - for (int i = startInclusive; i <= endInclusive; i++) { - sumOfSquares += i * i; - } - return sumOfSquares; + return IntStream.rangeClosed(startInclusive, endInclusive) + .map(a -> a * a) + .sum(); } }