Skip to content

Commit

Permalink
added implementation for StreamPractice and CandidateValidator
Browse files Browse the repository at this point in the history
  • Loading branch information
vadymhrnk committed Oct 29, 2023
1 parent c115d4e commit 2d7bea4
Show file tree
Hide file tree
Showing 2 changed files with 66 additions and 56 deletions.
23 changes: 21 additions & 2 deletions src/main/java/practice/CandidateValidator.java
Original file line number Diff line number Diff line change
@@ -1,5 +1,24 @@
package practice;

public class CandidateValidator {
//write your code here
import java.util.function.Predicate;
import model.Candidate;

public class CandidateValidator implements Predicate<Candidate> {
private static final String REGEX_DASH = "-";
private static final int FROM_YEAR_INDEX = 0;
private static final int TO_YEAR_INDEX = 1;
private static final int MIN_AGE = 35;
private static final String UKRAINIAN = "Ukrainian";
private static final int MIN_TOTAL_YEARS = 10;

@Override
public boolean test(Candidate candidate) {
String[] periods = candidate.getPeriodsInUkr().split(REGEX_DASH);
int totalYears = Integer.parseInt(periods[TO_YEAR_INDEX])
- Integer.parseInt(periods[FROM_YEAR_INDEX]);
return candidate.getAge() >= MIN_AGE
&& candidate.isAllowedToVote()
&& candidate.getNationality().equals(UKRAINIAN)
&& totalYears >= MIN_TOTAL_YEARS;
}
}
99 changes: 45 additions & 54 deletions src/main/java/practice/StreamPractice.java
Original file line number Diff line number Diff line change
@@ -1,80 +1,71 @@
package practice;

import java.util.Collections;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import model.Candidate;
import model.Cat;
import model.Person;

public class StreamPractice {
/**
* Given list of strings where each element contains 1+ numbers:
* input = {"5,30,100", "0,22,7", ...}
* return min integer value. One more thing - we're interested in even numbers.
* If there is no needed data throw RuntimeException with message
* "Can't get min value from list: < Here is our input 'numbers' >"
*/
private static final String REGEX_COMMA = ",";
private static final String NO_SUCH_DATA_MESSAGE = "Can't get min value from list: ";
private CandidateValidator candidateValidator = new CandidateValidator();

public int findMinEvenNumber(List<String> numbers) {
return 0;
return numbers.stream()
.map(s -> s.split(REGEX_COMMA))
.flatMap(Arrays::stream)
.mapToInt(Integer::valueOf)
.filter(i -> i % 2 == 0)
.min()
.orElseThrow(() -> new RuntimeException(
NO_SUCH_DATA_MESSAGE + Collectors.toList()));
}

/**
* Given a List of Integer numbers,
* return the average of all odd numbers from the list or throw NoSuchElementException.
* But before that subtract 1 from each element on an odd position (having the odd index).
*/
public Double getOddNumsAverage(List<Integer> numbers) {
return 0D;
return IntStream.range(0, numbers.size())
.map(i -> (i % 2 == 1) ? numbers.get(i) - 1 : numbers.get(i))
.filter(num -> num % 2 != 0)
.mapToDouble(Double::valueOf)
.average()
.orElseThrow();
}

/**
* Given a List of `Person` instances (having `name`, `age` and `sex` fields),
* for example, `Arrays.asList( new Person(«Victor», 16, Sex.MAN),
* new Person(«Helen», 42, Sex.WOMAN))`,
* select from the List only men whose age is from `fromAge` to `toAge` inclusively.
* <p>
* Example: select men who can be recruited to army (from 18 to 27 years old inclusively).
*/
public List<Person> selectMenByAge(List<Person> peopleList, int fromAge, int toAge) {
return Collections.emptyList();
return peopleList.stream()
.filter(p -> p.getSex().equals(Person.Sex.MAN))
.filter(p -> p.getAge() >= fromAge)
.filter(p -> p.getAge() <= toAge)
.collect(Collectors.toList());
}

/**
* Given a List of `Person` instances (having `name`, `age` and `sex` fields),
* for example, `Arrays.asList( new Person(«Victor», 16, Sex.MAN),
* new Person(«Helen», 42, Sex.WOMAN))`,
* select from the List only people whose age is from `fromAge` and to `maleToAge` (for men)
* or to `femaleToAge` (for women) inclusively.
* <p>
* Example: select people of working age
* (from 18 y.o. and to 60 y.o. for men and to 55 y.o. for women inclusively).
*/
public List<Person> getWorkablePeople(int fromAge, int femaleToAge,
int maleToAge, List<Person> peopleList) {
return Collections.emptyList();
return peopleList.stream()
.filter(p -> p.getAge() >= fromAge)
.filter(p -> p.getSex().equals(Person.Sex.WOMAN) && p.getAge() <= femaleToAge
|| p.getSex().equals(Person.Sex.MAN) && p.getAge() <= maleToAge)
.collect(Collectors.toList());
}

/**
* Given a List of `Person` instances (having `name`, `age`, `sex` and `cats` fields,
* and each `Cat` having a `name` and `age`),
* return the names of all cats whose owners are women from `femaleAge` years old inclusively.
*/
public List<String> getCatsNames(List<Person> peopleList, int femaleAge) {
return Collections.emptyList();
return peopleList.stream()
.filter(p -> p.getSex().equals(Person.Sex.WOMAN))
.filter(p -> p.getAge() >= femaleAge)
.map(Person::getCats)
.flatMap(Collection::stream)
.map(Cat::getName)
.collect(Collectors.toList());
}

/**
* Your help with a election is needed. Given list of candidates, where each element
* has Candidate.class type.
* Check which candidates are eligible to apply for president position and return their
* names sorted alphabetically.
* The requirements are: person should be older than 35 years, should be allowed to vote,
* have nationality - 'Ukrainian'
* and live in Ukraine for 10 years. For the last requirement use field periodsInUkr,
* which has following view: "2002-2015"
* We want to reuse our validation in future, so let's write our own impl of Predicate
* parametrized with Candidate in CandidateValidator.
*/
public List<String> validateCandidates(List<Candidate> candidates) {
return Collections.emptyList();
return candidates.stream()
.filter(candidateValidator)
.map(Candidate::getName)
.sorted()
.collect(Collectors.toList());
}
}

0 comments on commit 2d7bea4

Please sign in to comment.