From a8271073eb912012c1c286cec129cdb78fb47519 Mon Sep 17 00:00:00 2001
From: artificialLeo <horkovenko.k@gmail.com>
Date: Sun, 29 Oct 2023 14:03:03 +0200
Subject: [PATCH] added 3 predicates and new class, reworked existing person
 predicate

---
 .../java/practice/CandidateValidator.java     | 19 ++++++++----
 src/main/java/practice/PersonValidator.java   | 26 +++++++++++++++++
 src/main/java/practice/StreamPractice.java    | 29 ++++++++++---------
 3 files changed, 56 insertions(+), 18 deletions(-)
 create mode 100644 src/main/java/practice/PersonValidator.java

diff --git a/src/main/java/practice/CandidateValidator.java b/src/main/java/practice/CandidateValidator.java
index 388925f3e..576d0e42f 100644
--- a/src/main/java/practice/CandidateValidator.java
+++ b/src/main/java/practice/CandidateValidator.java
@@ -4,12 +4,21 @@
 import model.Candidate;
 
 public class CandidateValidator implements Predicate<Candidate> {
+    private static final int MINIMUM_AGE = 35;
+    private static final String UKRAINIAN_NATIONALITY = "Ukrainian";
+    private static final int MINIMUM_UKR_PERIOD = 10;
+
     @Override
     public boolean test(Candidate candidate) {
-        return candidate.getAge() >= 35
-                && candidate.isAllowedToVote()
-                && candidate.getNationality().equals("Ukrainian")
-                && Integer.parseInt(candidate.getPeriodsInUkr().split("-")[1])
-                - Integer.parseInt(candidate.getPeriodsInUkr().split("-")[0]) >= 10;
+        String[] periods = candidate.getPeriodsInUkr().split("-");
+        int startYear = Integer.parseInt(periods[0]);
+        int endYear = Integer.parseInt(periods[1]);
+
+        boolean isMinimumAge = candidate.getAge() >= MINIMUM_AGE;
+        boolean isAllowedToVote = candidate.isAllowedToVote();
+        boolean isUkrainian = candidate.getNationality().equals(UKRAINIAN_NATIONALITY);
+        boolean hasMinimumUkrPeriod = endYear - startYear >= MINIMUM_UKR_PERIOD;
+
+        return isMinimumAge && isAllowedToVote && isUkrainian && hasMinimumUkrPeriod;
     }
 }
diff --git a/src/main/java/practice/PersonValidator.java b/src/main/java/practice/PersonValidator.java
new file mode 100644
index 000000000..013ae2080
--- /dev/null
+++ b/src/main/java/practice/PersonValidator.java
@@ -0,0 +1,26 @@
+package practice;
+
+import java.util.function.Predicate;
+import model.Person;
+
+public class PersonValidator {
+    public static Predicate<Person> isManBetweenAges(int fromAge, int toAge) {
+        return p -> p.getSex() == Person.Sex.MAN
+                && p.getAge() >= fromAge
+                && p.getAge() <= toAge;
+    }
+
+    public static Predicate<Person> selectPeopleByAge(int fromAge, int maleToAge, int femaleToAge) {
+        Predicate<Person> isManBetweenAges = PersonValidator.isManBetweenAges(fromAge, maleToAge);
+
+        return p -> {
+            int ageLimit = (p.getSex() == Person.Sex.MAN) ? maleToAge : femaleToAge;
+            return p.getAge() >= fromAge && p.getAge() <= ageLimit;
+        };
+    }
+
+    public static Predicate<Person> isElderlyWoman(int femaleAge) {
+        return p -> p.getSex() == Person.Sex.WOMAN && p.getAge() >= femaleAge;
+    }
+}
+
diff --git a/src/main/java/practice/StreamPractice.java b/src/main/java/practice/StreamPractice.java
index 631d4caa7..e9f103437 100644
--- a/src/main/java/practice/StreamPractice.java
+++ b/src/main/java/practice/StreamPractice.java
@@ -3,6 +3,7 @@
 import java.util.Arrays;
 import java.util.List;
 import java.util.NoSuchElementException;
+import java.util.function.Predicate;
 import java.util.stream.IntStream;
 import model.Candidate;
 import model.Cat;
@@ -13,8 +14,8 @@ public class StreamPractice {
     public int findMinEvenNumber(List<String> numbers) {
         return numbers.stream()
                 .flatMapToInt(s -> Arrays.stream(s.split(","))
-                        .mapToInt(Integer::parseInt)
-                        .filter(num -> num % 2 == 0))
+                .mapToInt(Integer::parseInt)
+                .filter(num -> num % 2 == 0))
                 .min()
                 .orElseThrow(() ->
                         new RuntimeException("Can't get min value from list " + numbers));
@@ -24,33 +25,35 @@ public Double getOddNumsAverage(List<Integer> numbers) {
         return IntStream.range(0, numbers.size())
                 .map(i -> (i % 2 == 1) ? numbers.get(i) - 1 : numbers.get(i))
                 .filter(num -> num % 2 != 0)
-                .boxed()
-                .toList().stream()
-                .mapToInt(Integer::intValue)
                 .average()
                 .orElseThrow(() -> new NoSuchElementException("List is empty"));
     }
 
     public List<Person> selectMenByAge(List<Person> peopleList, int fromAge, int toAge) {
+        Predicate<Person> isManBetweenAges = PersonValidator
+                .isManBetweenAges(fromAge, toAge);
+
         return peopleList.stream()
-                .filter(p -> p.getSex() == Person.Sex.MAN
-                        && p.getAge() >= fromAge
-                        && p.getAge() <= toAge)
+                .filter(isManBetweenAges)
                 .toList();
     }
 
     public List<Person> getWorkablePeople(int fromAge, int femaleToAge,
                                           int maleToAge, List<Person> peopleList) {
+        Predicate<Person> workablePersonPredicate = PersonValidator
+                .selectPeopleByAge(fromAge, maleToAge, femaleToAge);
+
         return peopleList.stream()
-                .filter(p -> {
-                    int ageLimit = (p.getSex() == Person.Sex.MAN) ? maleToAge : femaleToAge;
-                    return p.getAge() >= fromAge && p.getAge() <= ageLimit;
-                }).toList();
+                .filter(workablePersonPredicate)
+                .toList();
     }
 
     public List<String> getCatsNames(List<Person> peopleList, int femaleAge) {
+        Predicate<Person> elderlyWomanPredicate = PersonValidator
+                .isElderlyWoman(femaleAge);
+
         return peopleList.stream()
-                .filter(p -> p.getSex() == Person.Sex.WOMAN && p.getAge() >= femaleAge)
+                .filter(elderlyWomanPredicate)
                 .flatMap(p -> p.getCats().stream())
                 .map(Cat::getName)
                 .toList();