From 35ec87a0f21202cfa042908bd1049e8ce102e8bb Mon Sep 17 00:00:00 2001
From: parte-Ajinkya <112530584+parte-Ajinkya@users.noreply.github.com>
Date: Wed, 19 Oct 2022 22:09:18 +0530
Subject: [PATCH] Create java-hash-set examples

---
 java-hash-set examples | 142 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 142 insertions(+)
 create mode 100644 java-hash-set examples

diff --git a/java-hash-set examples b/java-hash-set examples
new file mode 100644
index 0000000..dbc7a1b
--- /dev/null
+++ b/java-hash-set examples	
@@ -0,0 +1,142 @@
+import java.util.HashSet;
+import java.util.Set;
+
+public class CreateHashSetExample {
+    public static void main(String[] args) {
+        // Creating a HashSet
+        Set<String> daysOfWeek = new HashSet<>();
+
+        // Adding new elements to the HashSet
+        daysOfWeek.add("Monday");
+        daysOfWeek.add("Tuesday");
+        daysOfWeek.add("Wednesday");
+        daysOfWeek.add("Thursday");
+        daysOfWeek.add("Friday");
+        daysOfWeek.add("Saturday");
+        daysOfWeek.add("Sunday");
+
+        // Adding duplicate elements will be ignored
+        daysOfWeek.add("Monday");
+
+        System.out.println(daysOfWeek);
+    }
+}
+
+***************************************************************************************************************************************************************************
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class CreateHashSetFromCollectionExample {
+    public static void main(String[] args) {
+        List<Integer> numbersDivisibleBy5 = new ArrayList<>();
+        numbersDivisibleBy5.add(5);
+        numbersDivisibleBy5.add(10);
+        numbersDivisibleBy5.add(15);
+        numbersDivisibleBy5.add(20);
+        numbersDivisibleBy5.add(25);
+
+        List<Integer> numbersDivisibleBy3 = new ArrayList<>();
+        numbersDivisibleBy3.add(3);
+        numbersDivisibleBy3.add(6);
+        numbersDivisibleBy3.add(9);
+        numbersDivisibleBy3.add(12);
+        numbersDivisibleBy3.add(15);
+
+        // Creating a HashSet from another collection (ArrayList)
+        Set<Integer> numbersDivisibleBy5Or3 = new HashSet<>(numbersDivisibleBy5);
+
+        // Adding all the elements from an existing collection to a HashSet
+        numbersDivisibleBy5Or3.addAll(numbersDivisibleBy3);
+
+        System.out.println(numbersDivisibleBy5Or3);
+    }
+}
+***************************************************************************************************************************************************************************
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class HashSetRemoveExample {
+    public static void main(String[] args) {
+        Set<Integer> numbers = new HashSet<>();
+        numbers.add(2);
+        numbers.add(3);
+        numbers.add(4);
+        numbers.add(5);
+        numbers.add(6);
+        numbers.add(7);
+        numbers.add(8);
+        numbers.add(9);
+        numbers.add(10);
+
+        System.out.println("numbers : " + numbers);
+
+        // Remove an element from a HashSet (The remove() method returns false if the element does not exist in the HashSet)
+        boolean isRemoved = numbers.remove(10);
+        System.out.println("After remove(10) => " + numbers);
+
+        // Remove all elements belonging to a given collection from a HashSet
+        List<Integer> perfectSquares = new ArrayList<>();
+        perfectSquares.add(4);
+        perfectSquares.add(9);
+
+        numbers.removeAll(perfectSquares);
+        System.out.println("After removeAll(perfectSquares) => " + numbers);
+
+        // Remove all elements matching a given predicate
+        numbers.removeIf(num -> num % 2 == 0);
+        System.out.println("After removeIf() => " + numbers);
+
+        // Remove all elements from HashSet (clear it completely)
+        numbers.clear();
+        System.out.println("After clear() => " + numbers);
+    }
+}
+
+***************************************************************************************************************************************************************************
+
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Set;
+
+public class IterateOverHashSetExample {
+    public static void main(String[] args) {
+        Set<String> programmingLanguages = new HashSet<>();
+        programmingLanguages.add("C");
+        programmingLanguages.add("C++");
+        programmingLanguages.add("Java");
+        programmingLanguages.add("Python");
+        programmingLanguages.add("PHP");
+        programmingLanguages.add("Ruby");
+
+        System.out.println("=== Iterate over a HashSet using Java 8 forEach and lambda ===");
+        programmingLanguages.forEach(programmingLanguage -> {
+            System.out.println(programmingLanguage);
+        });
+
+        System.out.println("=== Iterate over a HashSet using iterator() ===");
+        Iterator<String> programmingLanguageIterator = programmingLanguages.iterator();
+        while (programmingLanguageIterator.hasNext()) {
+            String programmingLanguage = programmingLanguageIterator.next();
+            System.out.println(programmingLanguage);
+        }
+
+        System.out.println("=== Iterate over a HashSet using iterator() and Java 8 forEachRemaining() method ===");
+        programmingLanguageIterator = programmingLanguages.iterator();
+        programmingLanguageIterator.forEachRemaining(programmingLanguage -> {
+            System.out.println(programmingLanguage);
+        });
+
+        System.out.println("=== Iterate over a HashSet using simple for-each loop ===");
+        for(String programmingLanguage: programmingLanguages) {
+            System.out.println(programmingLanguage);
+        }
+    }
+}
+
+
+***************************************************************************************************************************************************************************