{"id":33635,"date":"2023-02-11T04:41:49","date_gmt":"2023-02-10T23:11:49","guid":{"rendered":"https:\/\/jassweb.com\/solved\/solved-how-list-methods-work-duplicate\/"},"modified":"2023-02-11T04:41:49","modified_gmt":"2023-02-10T23:11:49","slug":"solved-how-list-methods-work-duplicate","status":"publish","type":"post","link":"https:\/\/jassweb.com\/solved\/solved-how-list-methods-work-duplicate\/","title":{"rendered":"[Solved] how list methods work? [duplicate]"},"content":{"rendered":"<p> [ad_1]<br \/>\n<\/p>\n<div id=\"answer-14252497\" class=\"answer js-answer accepted-answer js-accepted-answer\" data-answerid=\"14252497\" data-parentid=\"14252444\" data-score=\"2\" data-position-on-page=\"1\" data-highest-scored=\"1\" data-question-has-accepted-highest-score=\"1\" itemprop=\"acceptedAnswer\" itemscope itemtype=\"https:\/\/schema.org\/Answer\">\n<div class=\"post-layout\">\n<div class=\"votecell post-layout--left\"><\/div>\n<div class=\"answercell post-layout--right\">\n<div class=\"s-prose js-post-body\" itemprop=\"text\">\n<pre><code>List&lt;Book&gt; list\n<\/code><\/pre>\n<p>Here list is a reference to an object, not an object itself. When you call interface methods on this reference, you are actually calling the overridden methods of some concrete class that this reference points to. <\/p>\n<p>To illustrate <\/p>\n<pre><code>List&lt;Book&gt; list = new List&lt;Book&gt;(); \/\/Illegal\nList&lt;Book&gt; list = new ArrayList&lt;Book&gt;(); \/\/legal ArrayList is a concrete implementation of list.\n<\/code><\/pre>\n<p>That is the power of interfaces, I can do stuff with this reference without worrying about how it works or how it is implemented.<\/p>\n<\/p><\/div>\n<div class=\"mt24\"><\/div>\n<\/div>\n<p>            <span class=\"d-none\" itemprop=\"commentCount\"><\/span> <\/p><\/div>\n<\/div>\n<p>[ad_2]<\/p>\n<p>solved how list methods work? [duplicate] <\/p>\n","protected":false},"excerpt":{"rendered":"<p>[ad_1] List&lt;Book&gt; list Here list is a reference to an object, not an object itself. When you call interface methods on this reference, you are actually calling the overridden methods of some concrete class that this reference points to. To illustrate List&lt;Book&gt; list = new List&lt;Book&gt;(); \/\/Illegal List&lt;Book&gt; list = new ArrayList&lt;Book&gt;(); \/\/legal ArrayList is &#8230; <a title=\"[Solved] how list methods work? [duplicate]\" class=\"read-more\" href=\"https:\/\/jassweb.com\/solved\/solved-how-list-methods-work-duplicate\/\" aria-label=\"More on [Solved] how list methods work? [duplicate]\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[320],"tags":[592,323],"class_list":["post-33635","post","type-post","status-publish","format-standard","hentry","category-solved","tag-jakarta-ee","tag-java"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v26.5 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>[Solved] how list methods work? [duplicate] - JassWeb<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/jassweb.com\/solved\/solved-how-list-methods-work-duplicate\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"[Solved] how list methods work? [duplicate] - JassWeb\" \/>\n<meta property=\"og:description\" content=\"[ad_1] List&lt;Book&gt; list Here list is a reference to an object, not an object itself. When you call interface methods on this reference, you are actually calling the overridden methods of some concrete class that this reference points to. To illustrate List&lt;Book&gt; list = new List&lt;Book&gt;(); \/\/Illegal List&lt;Book&gt; list = new ArrayList&lt;Book&gt;(); \/\/legal ArrayList is ... 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