{"id":820,"date":"2024-11-30T08:45:59","date_gmt":"2024-11-30T08:45:59","guid":{"rendered":"https:\/\/vithleshgupta.com\/?page_id=820"},"modified":"2025-08-06T01:50:02","modified_gmt":"2025-08-06T01:50:02","slug":"hashset","status":"publish","type":"page","link":"https:\/\/vithleshgupta.com\/index.php\/hashset\/","title":{"rendered":"HashSet"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"820\" class=\"elementor elementor-820\">\n\t\t\t\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-381ff20 elementor-section-full_width elementor-section-height-default elementor-section-height-default\" data-id=\"381ff20\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-8e0df96 elementor-hidden-mobile\" data-id=\"8e0df96\" data-element_type=\"column\" data-settings=\"{&quot;background_background&quot;:&quot;gradient&quot;}\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-0c8a2c5 elementor-widget elementor-widget-sidebar\" data-id=\"0c8a2c5\" data-element_type=\"widget\" data-widget_type=\"sidebar.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<aside id=\"block-2\" class=\"widget widget_block\"><p><nav id=\"bellows-main-6\" class=\"bellows bellows-nojs bellows-main bellows-source-menu bellows-align-full bellows-skin-grey-material bellows-type- bellows-expand-current\"><ul id=\"menu-sidebarmenu\" class=\"bellows-nav\" data-bellows-config=\"main\"><li id=\"menu-item-653\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-current_page_parent bellows-menu-item-has-children bellows-menu-item-653 bellows-item-level-0\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/helloworld\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Learn Java<\/span><button class=\"bellows-subtoggle\" aria-label=\"Toggle Submenu\"><i class=\"bellows-subtoggle-icon-expand fa fa-chevron-down\"><\/i><i class=\"bellows-subtoggle-icon-collapse fa fa-chevron-up\"><\/i><\/button><\/a>\n<ul class=\"bellows-submenu\">\n\t<li id=\"menu-item-970\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-home bellows-menu-item-970 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Java Basics Part 1<\/span><\/a><\/li>\n\t<li id=\"menu-item-1033\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-1033 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/java-basics-part-2\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Java Basics Part 2<\/span><\/a><\/li>\n\t<li id=\"menu-item-1045\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-1045 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/java-oops-part-1\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Java OOPS Part 1<\/span><\/a><\/li>\n\t<li id=\"menu-item-1044\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-1044 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/java-oops-part-2\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Java OOPS Part 2<\/span><\/a><\/li>\n\t<li id=\"menu-item-658\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-658 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/hello-world\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Hello World<\/span><\/a><\/li>\n\t<li id=\"menu-item-893\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-893 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/datatypes\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">DataTypes<\/span><\/a><\/li>\n\t<li id=\"menu-item-659\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-659 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/if-else-condition\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">If Else 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class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">While Loop<\/span><\/a><\/li>\n\t<li id=\"menu-item-657\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-657 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/for-loop\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">For Loop<\/span><\/a><\/li>\n\t<li id=\"menu-item-656\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-656 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/do-while-loop\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Do While Loop<\/span><\/a><\/li>\n\t<li id=\"menu-item-654\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-654 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/break-statement\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Break Statement<\/span><\/a><\/li>\n\t<li id=\"menu-item-655\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-655 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/continue-statement\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Continue Statement<\/span><\/a><\/li>\n\t<li id=\"menu-item-786\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-786 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/try-catch-statement\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Try Catch Statement<\/span><\/a><\/li>\n\t<li id=\"menu-item-897\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-897 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/arraylist\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">ArrayList<\/span><\/a><\/li>\n\t<li id=\"menu-item-896\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-896 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/hashset\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">HashSet<\/span><\/a><\/li>\n\t<li id=\"menu-item-895\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-895 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/hashmap\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">HashMap<\/span><\/a><\/li>\n\t<li id=\"menu-item-892\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-892 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/iterate-hashmap\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Iterate HashMap<\/span><\/a><\/li>\n<\/ul>\n<\/li>\n<li id=\"menu-item-724\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-has-children bellows-menu-item-724 bellows-item-level-0\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/learn-selenium\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Learn Selenium<\/span><button class=\"bellows-subtoggle\" aria-label=\"Toggle Submenu\"><i class=\"bellows-subtoggle-icon-expand fa fa-chevron-down\"><\/i><i class=\"bellows-subtoggle-icon-collapse fa fa-chevron-up\"><\/i><\/button><\/a>\n<ul class=\"bellows-submenu\">\n\t<li id=\"menu-item-741\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-741 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/first-program-selenium\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">First Program \u2013 Selenium<\/span><\/a><\/li>\n\t<li id=\"menu-item-728\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-728 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/revise-selenium\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Revise Selenium<\/span><\/a><\/li>\n\t<li id=\"menu-item-1069\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-1069 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/html-css-javascript\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">HTML CSS JavaScript<\/span><\/a><\/li>\n\t<li id=\"menu-item-1068\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-1068 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/css-selector\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">CSS Selector<\/span><\/a><\/li>\n\t<li id=\"menu-item-1067\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-1067 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/xpath-types\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Xpath types<\/span><\/a><\/li>\n\t<li id=\"menu-item-765\" class=\"bellows-menu-item bellows-menu-item-type-post_type bellows-menu-item-object-page bellows-menu-item-765 bellows-item-level-1\"><a  href=\"https:\/\/vithleshgupta.com\/index.php\/practice-page\/\" class=\"bellows-target menu-link\"><span class=\"bellows-target-title bellows-target-text\">Practice Page<\/span><\/a><\/li>\n<\/ul>\n<\/li>\n<\/ul><\/nav><\/p>\n<\/aside>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-d2a1565\" data-id=\"d2a1565\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<section class=\"elementor-section elementor-inner-section elementor-element elementor-element-68768b2 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"68768b2\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-inner-column elementor-element elementor-element-6df6bd9\" data-id=\"6df6bd9\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-ff6a663 elementor-widget__width-initial elementor-widget elementor-widget-text-editor\" data-id=\"ff6a663\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.14.0 - 26-06-2023 *\/\n.elementor-widget-text-editor.elementor-drop-cap-view-stacked .elementor-drop-cap{background-color:#69727d;color:#fff}.elementor-widget-text-editor.elementor-drop-cap-view-framed .elementor-drop-cap{color:#69727d;border:3px solid;background-color:transparent}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap{margin-top:8px}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap-letter{width:1em;height:1em}.elementor-widget-text-editor .elementor-drop-cap{float:left;text-align:center;line-height:1;font-size:50px}.elementor-widget-text-editor .elementor-drop-cap-letter{display:inline-block}<\/style>\t\t\t\t<p style=\"margin-top: 0.5em; margin-bottom: 1em; color: #202122; font-family: sans-serif; font-size: 20px; font-style: normal;\"><span style=\"color: #ff0000;\"><b>HashSet &#8211; In Java<\/b><\/span><\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-inner-section elementor-element elementor-element-8110715 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"8110715\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-inner-column elementor-element elementor-element-f65b2ca\" data-id=\"f65b2ca\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-103c960 elementor-widget elementor-widget-code-highlight\" data-id=\"103c960\" data-element_type=\"widget\" data-widget_type=\"code-highlight.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"prismjs-default copy-to-clipboard \">\n\t\t\t<pre data-line=\"\" class=\"highlight-height language-javascript line-numbers\">\n\t\t\t\t<code readonly=\"true\" class=\"language-javascript\">\n\t\t\t\t\t<xmp>import java.util.ArrayList;\r\nimport java.util.HashMap;\r\nimport java.util.HashSet;\r\nimport java.util.Map;\r\n\r\npublic class Program3 {\r\n\r\n\tpublic static void main(String[] args) {\r\n\r\n\t\tHashSet<String> country = new HashSet<String>();\r\n\t\tcountry.add(\"India\");\r\n\t\tcountry.add(\"USA\");\r\n\t\tcountry.add(\"China\");\r\n\t\tcountry.add(\"Russia\");\r\n\t\tSystem.out.println(country);\r\n\r\n\t}\r\n}\r\n<\/xmp>\n\t\t\t\t<\/code>\n\t\t\t<\/pre>\n\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-inner-section elementor-element elementor-element-84460aa elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"84460aa\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-inner-column elementor-element elementor-element-f0923ce\" data-id=\"f0923ce\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap\">\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<div class=\"elementor-element elementor-element-1fc5897 elementor-widget elementor-widget-text-editor\" data-id=\"1fc5897\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c414c84 elementor-widget elementor-widget-text-editor\" data-id=\"c414c84\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p><strong>Output \u2013<\/strong><\/p><div style=\"background-color: #ffffff; padding: 0px 0px 0px 2px;\"><div style=\"color: #000000; background-color: #ffffff; font-family: 'Courier New'; font-size: 10pt; white-space: pre;\"><div style=\"background-color: #ffffff; padding: 0px 0px 0px 2px;\"><div style=\"color: #000000; background-color: #ffffff; font-family: 'Courier New'; font-size: 10pt; white-space: pre;\"><p style=\"margin: 0;\"><strong><span style=\"color: #000000;\">[USA, China, India, Russia]<\/span><\/strong><\/p><\/div><\/div><\/div><\/div><p data-start=\"587\" data-end=\"716\">Note: The <strong data-start=\"600\" data-end=\"620\">order may change<\/strong> every time you run the program. That\u2019s because <strong data-start=\"668\" data-end=\"715\"><code data-start=\"670\" data-end=\"679\">HashSet<\/code> does not maintain insertion order<\/strong>.<\/p><hr data-start=\"718\" data-end=\"721\" \/><h3 data-start=\"723\" data-end=\"750\">\ud83d\udd0d What is a <code data-start=\"740\" data-end=\"749\">HashSet<\/code>?<\/h3><ul data-start=\"752\" data-end=\"962\"><li data-start=\"752\" data-end=\"832\"><p data-start=\"754\" data-end=\"832\"><code data-start=\"754\" data-end=\"763\">HashSet<\/code> is a <strong data-start=\"769\" data-end=\"802\">collection of unique elements<\/strong> \u2014 duplicates are not allowed.<\/p><\/li><li data-start=\"833\" data-end=\"881\"><p data-start=\"835\" data-end=\"881\">It is part of Java\u2019s <strong data-start=\"856\" data-end=\"880\">Collection Framework<\/strong>.<\/p><\/li><li data-start=\"882\" data-end=\"962\"><p data-start=\"884\" data-end=\"962\">It is <strong data-start=\"890\" data-end=\"903\">unordered<\/strong> \u2014 the elements may not appear in the order you added them.<\/p><\/li><\/ul><h3 data-start=\"969\" data-end=\"989\">\ud83d\udca1 Key Features:<\/h3><div class=\"_tableContainer_16hzy_1\"><div class=\"_tableWrapper_16hzy_14 group flex w-fit flex-col-reverse\" tabindex=\"-1\"><table class=\"w-fit min-w-(--thread-content-width)\" data-start=\"991\" data-end=\"1360\"><thead data-start=\"991\" data-end=\"1064\"><tr data-start=\"991\" data-end=\"1064\"><th data-start=\"991\" data-end=\"1012\" data-col-size=\"sm\">Feature<\/th><th data-start=\"1012\" data-end=\"1064\" data-col-size=\"sm\">Description<\/th><\/tr><\/thead><tbody data-start=\"1139\" data-end=\"1360\"><tr data-start=\"1139\" data-end=\"1212\"><td data-start=\"1139\" data-end=\"1160\" data-col-size=\"sm\">No Duplicates<\/td><td data-col-size=\"sm\" data-start=\"1160\" data-end=\"1212\">Automatically ignores duplicate entries<\/td><\/tr><tr data-start=\"1213\" data-end=\"1286\"><td data-start=\"1213\" data-end=\"1234\" data-col-size=\"sm\">Fast Lookup<\/td><td data-col-size=\"sm\" data-start=\"1234\" data-end=\"1286\">Uses hashing for quick access<\/td><\/tr><tr data-start=\"1287\" data-end=\"1360\"><td data-start=\"1287\" data-end=\"1308\" data-col-size=\"sm\">No Order Guarantee<\/td><td data-col-size=\"sm\" data-start=\"1308\" data-end=\"1360\">Elements can appear in any order<\/td><\/tr><\/tbody><\/table><div class=\"sticky end-(--thread-content-margin) h-0 self-end select-none\"><div class=\"absolute end-0 flex items-end\">\u00a0<\/div><\/div><\/div><\/div><hr data-start=\"1362\" data-end=\"1365\" \/><h3 data-start=\"1367\" data-end=\"1398\">\u2757 Example: Adding Duplicate<\/h3><div class=\"contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary\"><div class=\"sticky top-9\"><div class=\"absolute end-0 bottom-0 flex h-9 items-center pe-2\">\u00a0<\/div><\/div><div class=\"overflow-y-auto p-4\" dir=\"ltr\">\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0country.add(&#8220;India&#8221;); \/\/ Duplicate<br \/>\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0System.out.println(country); \/\/ &#8220;India&#8221; will not be added again<code class=\"whitespace-pre! language-java\"><br \/><\/code><\/div><\/div><hr data-start=\"1512\" data-end=\"1515\" \/><h3 data-start=\"1517\" data-end=\"1550\">\ud83d\udd01 Looping Through a HashSet:<\/h3><div class=\"contain-inline-size rounded-2xl relative bg-token-sidebar-surface-primary\"><div class=\"sticky top-9\"><div class=\"absolute end-0 bottom-0 flex h-9 items-center pe-2\"><div class=\"bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs\">\u00a0<\/div><\/div><\/div><div class=\"overflow-y-auto p-4\" dir=\"ltr\"><code class=\"whitespace-pre! language-java\"><span class=\"hljs-keyword\">for<\/span> (String c : country) <\/code><code class=\"whitespace-pre! language-java\">{<br \/><\/code><\/div><div class=\"overflow-y-auto p-4\" dir=\"ltr\"><code class=\"whitespace-pre! language-java\">    System.out.println(<span class=\"hljs-string\">\"Country: \"<\/span> + c);<br \/><\/code><\/div><div class=\"overflow-y-auto p-4\" dir=\"ltr\"><code class=\"whitespace-pre! language-java\">}<br \/><\/code><\/div><\/div><hr data-start=\"1635\" data-end=\"1638\" \/><h3 data-start=\"1640\" data-end=\"1669\">\ud83d\udce6 When to Use <code data-start=\"1659\" data-end=\"1668\">HashSet<\/code>:<\/h3><ul data-start=\"1671\" data-end=\"1826\"><li data-start=\"1671\" data-end=\"1714\"><p data-start=\"1673\" data-end=\"1714\">When you need to store <strong data-start=\"1696\" data-end=\"1706\">unique<\/strong> values.<\/p><\/li><li data-start=\"1715\" data-end=\"1757\"><p data-start=\"1717\" data-end=\"1757\">When you <strong data-start=\"1726\" data-end=\"1756\">don\u2019t care about the order<\/strong>.<\/p><\/li><li data-start=\"1758\" data-end=\"1826\"><p data-start=\"1760\" data-end=\"1826\">Useful for things like tags, sets of IDs, or filtering duplicates.<\/p><\/li><\/ul><div style=\"background-color: #ffffff; padding: 0px 0px 0px 2px;\"><div style=\"color: #000000; background-color: #ffffff; font-family: 'Courier New'; font-size: 10pt; white-space: pre;\"><div style=\"background-color: #ffffff; padding: 0px 0px 0px 2px;\"><div style=\"color: #000000; background-color: #ffffff; font-family: 'Courier New'; font-size: 10pt; white-space: pre;\"><p style=\"margin: 0;\">\u00a0<\/p><\/div><\/div><p style=\"margin: 0;\">\u00a0<\/p><\/div><\/div>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>HashSet &#8211; In Java import java.util.ArrayList; import java.util.HashMap; import java.util.HashSet; import java.util.Map; public class Program3 { public static void main(String[] args) { HashSet country = new HashSet(); country.add(&#8220;India&#8221;); country.add(&#8220;USA&#8221;); country.add(&#8220;China&#8221;); country.add(&#8220;Russia&#8221;); System.out.println(country); } } Output \u2013 [USA, China, India, Russia] Note: The order may change every time you run the program. 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