{"id":94491,"date":"2026-04-12T21:18:53","date_gmt":"2026-04-12T14:18:53","guid":{"rendered":"https:\/\/itviec.com\/blog\/?p=94491"},"modified":"2026-04-12T21:18:55","modified_gmt":"2026-04-12T14:18:55","slug":"lap-trinh-huong-doi-trong-java","status":"publish","type":"post","link":"https:\/\/itviec.com\/blog\/lap-trinh-huong-doi-trong-java\/","title":{"rendered":"L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java: Gi\u1ea3i th\u00edch chi ti\u1ebft k\u00e8m v\u00ed d\u1ee5"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">N\u1ed9i dung b\u00e0i vi\u1ebft<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/itviec.com\/blog\/lap-trinh-huong-doi-trong-java\/#Tong_quan_ve_lap_trinh_huong_doi_tuong_trong_Java\" >T\u1ed5ng quan v\u1ec1 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng trong Java<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/itviec.com\/blog\/lap-trinh-huong-doi-trong-java\/#Tai_sao_nen_su_dung_OOP_trong_Java\" >T\u1ea1i sao n\u00ean s\u1eed d\u1ee5ng OOP trong Java?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/itviec.com\/blog\/lap-trinh-huong-doi-trong-java\/#4_tinh_chat_tru_cot_cua_OOP_trong_Java\" >4 t\u00ednh ch\u1ea5t tr\u1ee5 c\u1ed9t c\u1ee7a OOP trong Java<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/itviec.com\/blog\/lap-trinh-huong-doi-trong-java\/#Cac_cau_hoi_thuong_gap_ve_lap_trinh_huong_doi_tuong_Java\" >C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/itviec.com\/blog\/lap-trinh-huong-doi-trong-java\/#Ket_luan\" >K\u1ebft lu\u1eadn<\/a><\/li><\/ul><\/nav><\/div>\n\n<p><strong><em>Java \u0111\u01b0\u1ee3c xem l\u00e0 ng\u00f4n ng\u1eef \u0111\u1ea1i di\u1ec7n ti\u00eau bi\u1ec3u nh\u1ea5t cho OOP v\u00ec m\u1ecdi th\u00e0nh ph\u1ea7n trong Java \u0111\u1ec1u \u0111\u01b0\u1ee3c x\u00e2y d\u1ef1ng d\u1ef1a tr\u00ean c\u00e1c l\u1edbp v\u00e0 \u0111\u1ed1i t\u01b0\u1ee3ng. Vi\u1ec7c \u00e1p d\u1ee5ng l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng trong Java gi\u00fap b\u1ea1n t\u1ed1i \u01b0u h\u00f3a kh\u1ea3 n\u0103ng t\u00e1i s\u1eed d\u1ee5ng code, khi\u1ebfn h\u1ec7 th\u1ed1ng tr\u1edf n\u00ean linh ho\u1ea1t, d\u1ec5 d\u00e0ng m\u1edf r\u1ed9ng m\u00e0 kh\u00f4ng l\u00e0m ph\u00e1 v\u1ee1 c\u1ea5u tr\u00fac s\u1eb5n c\u00f3.<\/em><\/strong><\/p>\n\n\n\n<p>\u0110\u1ecdc b\u00e0i vi\u1ebft n\u00e0y \u0111\u1ec3 hi\u1ec3u r\u00f5 v\u1ec1:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>B\u1ea3n ch\u1ea5t l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng (OOP) l\u00e0 g\u00ec?&nbsp;<\/li>\n\n\n\n<li>Class v\u00e0 Object trong Java l\u00e0 g\u00ec?<\/li>\n\n\n\n<li>V\u00ec sao OOP quan tr\u1ecdng trong Java, \u0111\u1eb7c bi\u1ec7t trong c\u00e1c d\u1ef1 \u00e1n l\u1edbn?<\/li>\n\n\n\n<li>4 t\u00ednh ch\u1ea5t tr\u1ee5 c\u1ed9t c\u1ee7a OOP trong Java: \u0110\u00f3ng g\u00f3i, K\u1ebf th\u1eeba, \u0110a h\u00ecnh, Tr\u1eebu t\u01b0\u1ee3ng&nbsp;<\/li>\n\n\n\n<li>C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-t\u1ed5ng-quan-v\u1ec1-l\u1eadp-trinh-h\u01b0\u1edbng-d\u1ed1i-t\u01b0\u1ee3ng-trong-java\"><span class=\"ez-toc-section\" id=\"Tong_quan_ve_lap_trinh_huong_doi_tuong_trong_Java\"><\/span><strong>T\u1ed5ng quan v\u1ec1 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng trong Java<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-d\u1ecbnh-nghia-oop-trong-java\"><strong>\u0110\u1ecbnh ngh\u0129a OOP trong Java<\/strong><\/h3>\n\n\n\n<p>L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng (OOP) l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p lu\u1eadn l\u1eadp tr\u00ecnh d\u1ef1a tr\u00ean kh\u00e1i ni\u1ec7m v\u1ec1 c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng.&nbsp;<\/p>\n\n\n\n<p>Trong Java, OOP kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t t\u00ednh n\u0103ng m\u00e0 l\u00e0 \u0111i\u1ec3m c\u1ed1t l\u00f5i c\u1ee7a ng\u00f4n ng\u1eef n\u00e0y. Thay v\u00ec t\u1eadp trung v\u00e0o c\u00e1c b\u01b0\u1edbc th\u1ef1c hi\u1ec7n l\u1ec7nh, OOP t\u1eadp trung v\u00e0o vi\u1ec7c x\u00e1c \u0111\u1ecbnh c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng m\u00e0 ta mu\u1ed1n thao t\u00e1c (ai\/c\u00e1i g\u00ec) v\u00e0 c\u00e1ch ch\u00fang t\u01b0\u01a1ng t\u00e1c v\u1edbi nhau.<\/p>\n\n\n\n<p>Ngo\u00e0i Java, c\u00f3 r\u1ea5t nhi\u1ec1u ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh ph\u1ed5 bi\u1ebfn kh\u00e1c c\u0169ng \u00e1p d\u1ee5ng m\u1ea1nh m\u1ebd m\u00f4 h\u00ecnh L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng (OOP). D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t v\u00e0i v\u00ed d\u1ee5 ti\u00eau bi\u1ec3u:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong><a href=\"https:\/\/itviec.com\/blog\/python-la-gi\/\" target=\"_blank\" rel=\"noreferrer noopener\">Python<\/a>:<\/strong> L\u00e0 m\u1ed9t ng\u00f4n ng\u1eef \u0111a m\u00f4 h\u00ecnh, nh\u01b0ng OOP l\u00e0 m\u1ed9t trong nh\u1eefng phong c\u00e1ch l\u1eadp tr\u00ecnh ch\u00ednh c\u1ee7a n\u00f3. Python \u0111\u01b0\u1ee3c \u01b0a chu\u1ed9ng v\u00ec c\u00fa ph\u00e1p \u0111\u01a1n gi\u1ea3n, d\u1ec5 \u0111\u1ecdc v\u00e0 t\u00ednh linh ho\u1ea1t cao.<\/li>\n\n\n\n<li><strong><a href=\"https:\/\/itviec.com\/blog\/cpp-la-gi\/\" target=\"_blank\" rel=\"noreferrer noopener\">C++<\/a>:<\/strong> L\u00e0 ph\u1ea7n m\u1edf r\u1ed9ng c\u1ee7a ng\u00f4n ng\u1eef C v\u00e0 \u0111\u01b0\u1ee3c xem l\u00e0 m\u1ed9t trong nh\u1eefng ng\u00f4n ng\u1eef OOP m\u1ea1nh m\u1ebd nh\u1ea5t, \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i trong ph\u00e1t tri\u1ec3n game, h\u1ec7 \u0111i\u1ec1u h\u00e0nh v\u00e0 c\u00e1c \u1ee9ng d\u1ee5ng hi\u1ec7u su\u1ea5t cao.<\/li>\n\n\n\n<li><a href=\"https:\/\/dotnet.microsoft.com\/en-us\/languages\/csharp\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>C# (C-Sharp)<\/strong><\/a><strong>:<\/strong> \u0110\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi Microsoft, l\u00e0 m\u1ed9t ng\u00f4n ng\u1eef OOP hi\u1ec7n \u0111\u1ea1i, th\u01b0\u1eddng \u0111\u01b0\u1ee3c d\u00f9ng trong ph\u00e1t tri\u1ec3n \u1ee9ng d\u1ee5ng Windows, web (v\u1edbi .NET), v\u00e0 game (v\u1edbi Unity).<\/li>\n\n\n\n<li><strong><a href=\"https:\/\/itviec.com\/blog\/php-la-gi\/\" target=\"_blank\" rel=\"noreferrer noopener\">PHP<\/a>:<\/strong> Ban \u0111\u1ea7u l\u00e0 m\u1ed9t ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh h\u01b0\u1edbng th\u1ee7 t\u1ee5c, nh\u01b0ng c\u00e1c phi\u00ean b\u1ea3n hi\u1ec7n \u0111\u1ea1i \u0111\u00e3 h\u1ed7 tr\u1ee3 \u0111\u1ea7y \u0111\u1ee7 c\u00e1c t\u00ednh n\u0103ng c\u1ee7a OOP v\u00e0 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i trong ph\u00e1t tri\u1ec3n web.<\/li>\n\n\n\n<li><strong><a href=\"https:\/\/itviec.com\/blog\/ruby-on-rails\/\" target=\"_blank\" rel=\"noreferrer noopener\">Ruby<\/a>:<\/strong> M\u1ed9t ng\u00f4n ng\u1eef c\u00f3 tri\u1ebft l\u00fd t\u1eadp trung s\u00e2u s\u1eafc v\u00e0o OOP, n\u1ed5i ti\u1ebfng v\u1edbi s\u1ef1 thanh l\u1ecbch v\u00e0 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng nhi\u1ec1u trong ph\u00e1t tri\u1ec3n web th\u00f4ng qua framework Ruby on Rails.<\/li>\n\n\n\n<li><a href=\"https:\/\/squeak.org\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Smalltalk<\/strong><\/a><strong>:<\/strong> M\u1ed9t trong nh\u1eefng ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh \u0111\u1ea7u ti\u00ean \u0111\u01b0\u1ee3c t\u1ea1o ra \u0111\u1ec3 tr\u1edf th\u00e0nh m\u1ed9t ng\u00f4n ng\u1eef &#8220;thu\u1ea7n&#8221; h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng.<\/li>\n<\/ul>\n\n\n\n<p>M\u1ecdi th\u1ee9 trong Java, t\u1eeb c\u00e1c th\u01b0 vi\u1ec7n chu\u1ea9n \u0111\u1ebfn c\u00e1c \u1ee9ng d\u1ee5ng b\u1ea1n x\u00e2y d\u1ef1ng, \u0111\u1ec1u \u0111\u01b0\u1ee3c t\u1ed5 ch\u1ee9c d\u01b0\u1edbi d\u1ea1ng c\u00e1c L\u1edbp (Class) v\u00e0 \u0110\u1ed1i t\u01b0\u1ee3ng (Object).<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><em>\u0110\u1ecdc th\u00eam: <strong><a href=\"https:\/\/itviec.com\/blog\/oop-la-gi\/\" target=\"_blank\" rel=\"noreferrer noopener\">OOP l\u00e0 g\u00ec? 4 \u0111\u1eb7c t\u00ednh c\u01a1 b\u1ea3n c\u1ee7a OOP<\/a><\/strong><\/em><\/p>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-class-va-object-trong-java\"><strong>Class v\u00e0 Object trong Java<\/strong><\/h3>\n\n\n\n<p>Trong Java, m\u1ecdi logic t\u00ednh to\u00e1n v\u00e0 x\u1eed l\u00fd d\u1eef li\u1ec7u \u0111\u1ec1u xoay quanh m\u1ed1i quan h\u1ec7 gi\u1eefa Class v\u00e0 Object. \u0110\u1ec3 d\u1ec5 hi\u1ec3u, h\u00e3y coi Class l\u00e0 b\u1ea3n thi\u1ebft k\u1ebf tr\u00ean gi\u1ea5y v\u00e0 Object l\u00e0 s\u1ea3n ph\u1ea9m th\u1ef1c t\u1ebf \u0111\u01b0\u1ee3c ch\u1ebf t\u1ea1o t\u1eeb b\u1ea3n thi\u1ebft k\u1ebf \u0111\u00f3.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"h-class-l\u1edbp\"><strong>Class (L\u1edbp)<\/strong><\/h4>\n\n\n\n<p>Class l\u00e0 m\u1ed9t ki\u1ec3u d\u1eef li\u1ec7u do ng\u01b0\u1eddi d\u00f9ng \u0111\u1ecbnh ngh\u0129a. N\u00f3 \u0111\u00f3ng vai tr\u00f2 l\u00e0 m\u1ed9t c\u00e1i khu\u00f4n ho\u1eb7c <strong>b\u1ea3n thi\u1ebft k\u1ebf<\/strong> d\u00f9ng \u0111\u1ec3 m\u00f4 t\u1ea3 tr\u1ea1ng th\u00e1i v\u00e0 h\u00e0nh vi c\u1ee7a m\u1ed9t nh\u00f3m \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f9ng lo\u1ea1i.<\/p>\n\n\n\n<p>M\u1ed9t Class th\u00f4ng th\u01b0\u1eddng bao g\u1ed3m:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Thu\u1ed9c t\u00ednh (Fields\/Attributes):<\/strong> C\u00e1c bi\u1ebfn l\u01b0u tr\u1eef d\u1eef li\u1ec7u (tr\u1ea1ng th\u00e1i).<\/li>\n\n\n\n<li><strong>Ph\u01b0\u01a1ng th\u1ee9c (Methods):<\/strong> C\u00e1c h\u00e0m \u0111\u1ecbnh ngh\u0129a h\u00e0nh \u0111\u1ed9ng m\u00e0 \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n (h\u00e0nh vi).<\/li>\n\n\n\n<li><strong>H\u00e0m kh\u1edfi t\u1ea1o (Constructor):<\/strong> Ph\u01b0\u01a1ng th\u1ee9c \u0111\u1eb7c bi\u1ec7t d\u00f9ng \u0111\u1ec3 kh\u1edfi t\u1ea1o \u0111\u1ed1i t\u01b0\u1ee3ng.<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\" id=\"h-object-d\u1ed1i-t\u01b0\u1ee3ng\"><strong>Object (\u0110\u1ed1i t\u01b0\u1ee3ng)<\/strong><\/h4>\n\n\n\n<p>Object l\u00e0 m\u1ed9t <strong>th\u1ef1c th\u1ec3 c\u1ee5 th\u1ec3<\/strong> \u0111\u01b0\u1ee3c t\u1ea1o ra t\u1eeb Class. Khi m\u1ed9t \u0111\u1ed1i t\u01b0\u1ee3ng \u0111\u01b0\u1ee3c kh\u1edfi t\u1ea1o, b\u1ed9 nh\u1edb s\u1ebd \u0111\u01b0\u1ee3c c\u1ea5p ph\u00e1t \u0111\u1ec3 l\u01b0u tr\u1eef c\u00e1c gi\u00e1 tr\u1ecb c\u1ee5 th\u1ec3 cho c\u00e1c thu\u1ed9c t\u00ednh m\u00e0 Class \u0111\u00e3 \u0111\u1ecbnh ngh\u0129a.<\/p>\n\n\n\n<p>M\u1ed7i \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f3 ba \u0111\u1eb7c \u0111i\u1ec3m ch\u00ednh:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Tr\u1ea1ng th\u00e1i (State):<\/strong> \u0110\u01b0\u1ee3c th\u1ec3 hi\u1ec7n qua gi\u00e1 tr\u1ecb c\u1ee7a c\u00e1c thu\u1ed9c t\u00ednh.<\/li>\n\n\n\n<li><strong>H\u00e0nh vi (Behavior):<\/strong> \u0110\u01b0\u1ee3c th\u1ec3 hi\u1ec7n qua vi\u1ec7c g\u1ecdi c\u00e1c ph\u01b0\u01a1ng th\u1ee9c.<\/li>\n\n\n\n<li><strong>Danh t\u00ednh (Identity):<\/strong> M\u1ed7i \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f3 m\u1ed9t \u0111\u1ecba ch\u1ec9 b\u1ed9 nh\u1edb ri\u00eang bi\u1ec7t, ngay c\u1ea3 khi ch\u00fang c\u00f3 c\u00f9ng gi\u00e1 tr\u1ecb thu\u1ed9c t\u00ednh.<\/li>\n<\/ol>\n\n\n\n<p>V\u00ed d\u1ee5 minh h\u1ecda th\u1ef1c t\u1ebf:<\/p>\n\n\n\n<p>Gi\u1ea3 s\u1eed ta c\u1ea7n qu\u1ea3n l\u00fd c\u00e1c lo\u1ea1i xe h\u01a1i trong ph\u1ea7n m\u1ec1m:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Class Car:<\/strong> S\u1ebd \u0111\u1ecbnh ngh\u0129a c\u00e1c \u0111\u1eb7c \u0111i\u1ec3m chung nh\u01b0 <code>brand<\/code> (th\u01b0\u01a1ng hi\u1ec7u), color (m\u00e0u s\u1eafc), <code>maxSpeed<\/code> (t\u1ed1c \u0111\u1ed9 t\u1ed1i \u0111a) v\u00e0 c\u00e1c h\u00e0nh \u0111\u1ed9ng nh\u01b0 <code>start()<\/code> (kh\u1edfi \u0111\u1ed9ng), <code>brake()<\/code> (phanh).<\/li>\n\n\n\n<li><strong>Object <\/strong><strong>toyota<\/strong><strong>:<\/strong> L\u00e0 m\u1ed9t th\u1ef1c th\u1ec3 c\u00f3 brand = &#8220;Toyota&#8221;, color = &#8220;Red&#8221;.<\/li>\n\n\n\n<li><strong>Object <\/strong><strong>tesla<\/strong><strong>:<\/strong> L\u00e0 m\u1ed9t th\u1ef1c th\u1ec3 c\u00f3 brand = &#8220;Tesla&#8221;, color = &#8220;White&#8221;.<\/li>\n<\/ul>\n\n\n\n<p>C\u00e1ch tri\u1ec3n khai trong Java:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u0110\u1ecbnh ngh\u0129a l\u1edbp (Class)\nclass Car {\n    String brand;\n    \n    void drive() {\n        System.out.println(brand + \" is driving...\");\n    }\n}\n\npublic class Main {\n    public static void main(String&#91;] args) {\n        \/\/ Kh\u1edfi t\u1ea1o \u0111\u1ed1i t\u01b0\u1ee3ng (Object)\n        Car myCar = new Car(); \n        myCar.brand = \"Toyota\";\n        myCar.drive(); \/\/ K\u1ebft qu\u1ea3: Toyota is driving...\n    }\n}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-t\u1ea1i-sao-nen-s\u1eed-d\u1ee5ng-oop-trong-java\"><span class=\"ez-toc-section\" id=\"Tai_sao_nen_su_dung_OOP_trong_Java\"><\/span><strong>T\u1ea1i sao n\u00ean s\u1eed d\u1ee5ng OOP trong Java?<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Trong l\u1eadp tr\u00ecnh h\u01b0\u1edbng th\u1ee7 t\u1ee5c, khi d\u1ef1 \u00e1n ph\u00ecnh to, m\u00e3 ngu\u1ed3n th\u01b0\u1eddng tr\u1edf th\u00e0nh m\u1ed9t &#8220;n\u1ed3i l\u1ea9u th\u1eadp c\u1ea9m&#8221; v\u1edbi c\u00e1c h\u00e0m \u0111an xen ch\u1eb1ng ch\u1ecbt. M\u1ed9t thay \u0111\u1ed5i nh\u1ecf \u1edf h\u00e0m n\u00e0y c\u00f3 th\u1ec3 g\u00e2y l\u1ed7i d\u00e2y chuy\u1ec1n \u1edf n\u01a1i kh\u00e1c.<\/p>\n\n\n\n<p>Vi\u1ec7c \u00e1p d\u1ee5ng m\u00f4 h\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng gi\u00fap qu\u00e1 tr\u00ecnh ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m tr\u1edf n\u00ean khoa h\u1ecdc v\u00e0 hi\u1ec7u qu\u1ea3 h\u01a1n b\u1eb1ng c\u00e1ch:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-phan-tach-module-modularity\"><strong>Ph\u00e2n t\u00e1ch module (Modularity)<\/strong><\/h3>\n\n\n\n<p>Chia d\u1ef1 \u00e1n th\u00e0nh c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng \u0111\u1ed9c l\u1eadp. Khi c\u00f3 l\u1ed7i, b\u1ea1n ch\u1ec9 c\u1ea7n ki\u1ec3m tra v\u00e0 s\u1eeda \u0111\u1ed5i b\u00ean trong \u0111\u1ed1i t\u01b0\u1ee3ng \u0111\u00f3 m\u00e0 kh\u00f4ng l\u00e0m \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn to\u00e0n b\u1ed9 h\u1ec7 th\u1ed1ng.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-kh\u1ea3-nang-m\u1edf-r\u1ed9ng-scalability\"><strong>Kh\u1ea3 n\u0103ng m\u1edf r\u1ed9ng (Scalability)<\/strong><\/h3>\n\n\n\n<p>V\u1edbi c\u00e1c d\u1ef1 \u00e1n l\u1edbn c\u1ea7n th\u00eam t\u00ednh n\u0103ng m\u1edbi, b\u1ea1n ch\u1ec9 vi\u1ec7c t\u1ea1o ra c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng m\u1edbi ho\u1eb7c m\u1edf r\u1ed9ng c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng c\u0169 thay v\u00ec ph\u1ea3i vi\u1ebft l\u1ea1i c\u1ea5u tr\u00fac ch\u01b0\u01a1ng tr\u00ecnh.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-tai-s\u1eed-d\u1ee5ng-ma-ngu\u1ed3n\"><strong>T\u00e1i s\u1eed d\u1ee5ng m\u00e3 ngu\u1ed3n<\/strong><\/h3>\n\n\n\n<p>OOP gi\u00fap t\u1ed1i \u01b0u h\u00f3a c\u1ea5u tr\u00fac code th\u00f4ng qua kh\u1ea3 n\u0103ng t\u00e1i s\u1eed d\u1ee5ng. Nh\u1edd t\u00ednh k\u1ebf th\u1eeba, c\u00e1c l\u1edbp con c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng l\u1ea1i c\u00e1c thu\u1ed9c t\u00ednh v\u00e0 ph\u01b0\u01a1ng th\u1ee9c t\u1eeb l\u1edbp cha, gi\u00fap lo\u1ea1i b\u1ecf vi\u1ec7c vi\u1ebft l\u1ea1i c\u00e1c \u0111o\u1ea1n m\u00e3 c\u00f3 ch\u1ee9c n\u0103ng t\u01b0\u01a1ng t\u1ef1. Khi c\u1ea7n thay \u0111\u1ed5i m\u1ed9t logic chung, b\u1ea1n ch\u1ec9 c\u1ea7n c\u1eadp nh\u1eadt t\u1ea1i l\u1edbp g\u1ed1c, m\u1ecdi th\u00e0nh ph\u1ea7n k\u1ebf th\u1eeba s\u1ebd t\u1ef1 \u0111\u1ed9ng \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt.&nbsp;<\/p>\n\n\n\n<p>\u0110i\u1ec1u n\u00e0y gi\u00fap team Dev ph\u1ed1i h\u1ee3p l\u00e0m vi\u1ec7c tr\u00ean c\u00f9ng m\u1ed9t d\u1ef1 \u00e1n l\u1edbn m\u00e0 kh\u00f4ng b\u1ecb ch\u1ed3ng ch\u00e9o m\u00e3 ngu\u1ed3n, gi\u1ea3m thi\u1ec3u r\u1ee7i ro sai s\u00f3t khi d\u1ef1 \u00e1n m\u1edf r\u1ed9ng.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-tang-c\u01b0\u1eddng-tinh-b\u1ea3o-m\u1eadt\"><strong>T\u0103ng c\u01b0\u1eddng t\u00ednh b\u1ea3o m\u1eadt<\/strong><\/h3>\n\n\n\n<p>T\u00ednh \u0111\u00f3ng g\u00f3i trong Java cung c\u1ea5p c\u01a1 ch\u1ebf b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u nghi\u00eam ng\u1eb7t:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Che gi\u1ea5u d\u1eef li\u1ec7u:<\/strong> Vi\u1ec7c s\u1eed d\u1ee5ng c\u00e1c t\u1eeb kh\u00f3a truy c\u1eadp (access modifiers) nh\u01b0 private gi\u00fap ng\u0103n ch\u1eb7n c\u00e1c t\u00e1c \u0111\u1ed9ng tr\u1ef1c ti\u1ebfp t\u1eeb b\u00ean ngo\u00e0i v\u00e0o tr\u1ea1ng th\u00e1i n\u1ed9i b\u1ed9 c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng.<\/li>\n\n\n\n<li><strong>Giao di\u1ec7n l\u1eadp tr\u00ecnh (API) n\u1ed9i b\u1ed9:<\/strong> Ng\u01b0\u1eddi d\u00f9ng ch\u1ec9 c\u00f3 th\u1ec3 t\u01b0\u01a1ng t\u00e1c v\u1edbi \u0111\u1ed1i t\u01b0\u1ee3ng qua c\u00e1c ph\u01b0\u01a1ng th\u1ee9c \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a s\u1eb5n (Getter\/Setter), \u0111\u1ea3m b\u1ea3o d\u1eef li\u1ec7u lu\u00f4n \u0111\u01b0\u1ee3c ki\u1ec3m tra t\u00ednh h\u1ee3p l\u1ec7 tr\u01b0\u1edbc khi thay \u0111\u1ed5i.<\/li>\n\n\n\n<li><strong>M\u00f4 ph\u1ecfng th\u1ef1c t\u1ebf \u0111\u1ec3 t\u1ed1i \u01b0u t\u01b0 duy:&nbsp;<\/strong><\/li>\n<\/ul>\n\n\n\n<p>Thay v\u00ec x\u1eed l\u00fd c\u00e1c lu\u1ed3ng logic ph\u1ee9c t\u1ea1p v\u00e0 r\u1eddi r\u1ea1c, OOP cho ph\u00e9p l\u1eadp tr\u00ecnh vi\u00ean t\u1ed5 ch\u1ee9c m\u00e3 ngu\u1ed3n theo c\u00e1c th\u1ef1c th\u1ec3 th\u1ef1c t\u1ebf. C\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng trong code nh\u01b0 KhachHang, DonHang, hay SanPham ph\u1ea3n \u00e1nh ch\u00ednh x\u00e1c c\u00e1c th\u1ef1c th\u1ec3 trong d\u1ef1 \u00e1n.&nbsp;<\/p>\n\n\n\n<p>M\u1ed7i \u0111\u1ed1i t\u01b0\u1ee3ng t\u1ef1 qu\u1ea3n l\u00fd logic v\u00e0 d\u1eef li\u1ec7u ri\u00eang c\u1ee7a n\u00f3. C\u00e1ch ph\u00e2n chia n\u00e0y gi\u00fap c\u00e1c nh\u00f3m l\u1eadp tr\u00ecnh vi\u00ean c\u00f3 th\u1ec3 l\u00e0m vi\u1ec7c \u0111\u1ed9c l\u1eadp tr\u00ean t\u1eebng module m\u00e0 kh\u00f4ng g\u00e2y \u1ea3nh h\u01b0\u1edfng l\u1eabn nhau, \u0111\u1eb7c bi\u1ec7t quan tr\u1ecdng trong c\u00e1c d\u1ef1 \u00e1n l\u1edbn.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-4-tinh-ch\u1ea5t-tr\u1ee5-c\u1ed9t-c\u1ee7a-oop-trong-java\"><span class=\"ez-toc-section\" id=\"4_tinh_chat_tru_cot_cua_OOP_trong_Java\"><\/span>4 t\u00ednh ch\u1ea5t tr\u1ee5 c\u1ed9t c\u1ee7a OOP trong Java<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>S\u1ee9c m\u1ea1nh l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java n\u1eb1m \u1edf 4 \u0111\u1eb7c t\u00ednh c\u1ed1t l\u00f5i, gi\u00fap l\u1eadp tr\u00ecnh vi\u00ean x\u00e2y d\u1ef1ng nh\u1eefng h\u1ec7 th\u1ed1ng ph\u1ea7n m\u1ec1m chuy\u00ean nghi\u1ec7p v\u00e0 linh ho\u1ea1t.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-tinh-dong-goi-encapsulation\"><strong>T\u00ednh \u0110\u00f3ng g\u00f3i (Encapsulation)<\/strong><\/h3>\n\n\n\n<p>T\u00ednh \u0111\u00f3ng g\u00f3i l\u00e0 vi\u1ec7c che gi\u1ea5u c\u00e1c chi ti\u1ebft th\u1ef1c hi\u1ec7n b\u00ean trong c\u1ee7a m\u1ed9t \u0111\u1ed1i t\u01b0\u1ee3ng v\u00e0 ch\u1ec9 \u0111\u1ec3 l\u1ed9 ra m\u1ed9t giao di\u1ec7n giao ti\u1ebfp c\u1ea7n thi\u1ebft. H\u00e3y t\u01b0\u1edfng t\u01b0\u1ee3ng n\u00f3 nh\u01b0 m\u1ed9t vi\u00ean thu\u1ed1c: b\u1ea1n bi\u1ebft c\u00f4ng d\u1ee5ng c\u1ee7a n\u00f3 nh\u01b0ng kh\u00f4ng c\u1ea7n bi\u1ebft c\u00e1c th\u00e0nh ph\u1ea7n h\u00f3a h\u1ecdc b\u00ean trong \u0111\u01b0\u1ee3c n\u00e9n l\u1ea1i nh\u01b0 th\u1ebf n\u00e0o.<\/p>\n\n\n\n<p><strong>L\u1ee3i \u00edch c\u1ed1t l\u00f5i<\/strong>:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>B\u1ea3o m\u1eadt d\u1eef li\u1ec7u: Ng\u0103n ch\u1eb7n vi\u1ec7c d\u1eef li\u1ec7u b\u00ean trong \u0111\u1ed1i t\u01b0\u1ee3ng b\u1ecb thay \u0111\u1ed5i m\u1ed9t c\u00e1ch t\u00f9y ti\u1ec7n t\u1eeb b\u00ean ngo\u00e0i, \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u.<\/li>\n\n\n\n<li>Gi\u00fap l\u1eadp tr\u00ecnh vi\u00ean ki\u1ec3m so\u00e1t ch\u00ednh x\u00e1c c\u00e1ch d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c truy c\u1eadp v\u00e0 s\u1eeda \u0111\u1ed5i th\u00f4ng qua c\u00e1c ph\u01b0\u01a1ng th\u1ee9c \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a r\u00f5 r\u00e0ng.<\/li>\n<\/ul>\n\n\n\n<p><strong>C\u01a1 ch\u1ebf ho\u1ea1t \u0111\u1ed9ng:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Khai b\u00e1o c\u00e1c bi\u1ebfn\/thu\u1ed9c t\u00ednh l\u00e0 <code>private<\/code> (ch\u1ec9 c\u00f3 th\u1ec3 truy c\u1eadp b\u00ean trong Class \u0111\u00f3).<\/li>\n\n\n\n<li>Cung c\u1ea5p c\u00e1c h\u00e0m <code>public<\/code> (th\u01b0\u1eddng l\u00e0 Getter v\u00e0 Setter) \u0111\u1ec3 truy c\u1eadp v\u00e0 ch\u1ec9nh s\u1eeda c\u00e1c bi\u1ebfn <code>private<\/code> theo m\u1ed9t logic \u0111\u00e3 \u0111\u01b0\u1ee3c ki\u1ec3m so\u00e1t.<\/li>\n<\/ul>\n\n\n\n<p><strong>V\u00ed d\u1ee5 c\u00e1ch tri\u1ec3n khai:<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>class Student {\n    \/\/ 1. Thu\u1ed9c t\u00ednh \u0111\u01b0\u1ee3c khai b\u00e1o l\u00e0 private (\u0110\u00f3ng g\u00f3i)\n    private int age;\n\n    \/\/ 2. Ph\u01b0\u01a1ng th\u1ee9c Setter public \u0111\u1ec3 ki\u1ec3m so\u00e1t gi\u00e1 tr\u1ecb\n    public void setAge(int newAge) {\n        \/\/ Ch\u1ec9 cho ph\u00e9p g\u00e1n tu\u1ed5i n\u1ebfu gi\u00e1 tr\u1ecb h\u1ee3p l\u1ec7\n        if (newAge &gt; 0) {\n            age = newAge;\n        } else {\n            System.out.println(\"Tu\u1ed5i kh\u00f4ng h\u1ee3p l\u1ec7.\");\n        }\n    }\n\n    \/\/ 3. Ph\u01b0\u01a1ng th\u1ee9c Getter public \u0111\u1ec3 l\u1ea5y gi\u00e1 tr\u1ecb\n    public int getAge() {\n        return age;\n    }\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-tinh-k\u1ebf-th\u1eeba-inheritance\"><strong>T\u00ednh K\u1ebf th\u1eeba (Inheritance)<\/strong><\/h3>\n\n\n\n<p>T\u00ednh K\u1ebf th\u1eeba cho ph\u00e9p m\u1ed9t l\u1edbp (g\u1ecdi l\u00e0 L\u1edbp Con hay Subclass) th\u1eeba h\u01b0\u1edfng l\u1ea1i c\u00e1c thu\u1ed9c t\u00ednh (fields) v\u00e0 h\u00e0nh vi (methods) t\u1eeb m\u1ed9t l\u1edbp kh\u00e1c (g\u1ecdi l\u00e0 L\u1edbp Cha hay Superclass.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p><em>\u0110\u1ecdc chi ti\u1ebft: <strong><a href=\"https:\/\/itviec.com\/blog\/ke-thua-trong-java\/\" target=\"_blank\" rel=\"noreferrer noopener\">K\u1ebf th\u1eeba trong Java: Kh\u00e1i ni\u1ec7m, ph\u00e2n lo\u1ea1i v\u00e0 nh\u1eefng l\u01b0u \u00fd<\/a><\/strong><\/em><\/p>\n<\/blockquote>\n\n\n\n<p><strong>L\u1ee3i \u00edch:<\/strong>&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>T\u00e1i s\u1eed d\u1ee5ng m\u00e3 ngu\u1ed3n (Code Reusability): L\u1edbp con t\u1ef1 \u0111\u1ed9ng c\u00f3 t\u1ea5t c\u1ea3 nh\u1eefng g\u00ec l\u1edbp cha c\u00f3, b\u1ea1n kh\u00f4ng c\u1ea7n ph\u1ea3i vi\u1ebft l\u1ea1i m\u00e3.<\/li>\n\n\n\n<li>Ph\u00e2n c\u1ea5p r\u00f5 r\u00e0ng: T\u1ea1o ra m\u1ed9t c\u1ea5u tr\u00fac ph\u00e2n c\u1ea5p t\u1ef1 nhi\u00ean v\u00e0 d\u1ec5 qu\u1ea3n l\u00fd cho ch\u01b0\u01a1ng tr\u00ecnh.<\/li>\n<\/ul>\n\n\n\n<p><strong>C\u01a1 ch\u1ebf ho\u1ea1t \u0111\u1ed9ng:<\/strong>\u00a0S\u1eed d\u1ee5ng t\u1eeb kh\u00f3a <a href=\"https:\/\/itviec.com\/blog\/extends-trong-java\/\" target=\"_blank\" rel=\"noreferrer noopener\">extends trong Java<\/a>. L\u1edbp con c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng l\u1ea1i m\u00e3 ngu\u1ed3n c\u1ee7a l\u1edbp cha m\u00e0 kh\u00f4ng c\u1ea7n vi\u1ebft l\u1ea1i, \u0111\u1ed3ng th\u1eddi c\u00f3 th\u1ec3 \u0111\u1ecbnh ngh\u0129a th\u00eam c\u00e1c \u0111\u1eb7c t\u00ednh m\u1edbi c\u1ee7a ri\u00eang n\u00f3.<\/p>\n\n\n\n<p><strong>V\u00ed d\u1ee5:<\/strong>&nbsp;<\/p>\n\n\n\n<p>L\u1edbp Animal (\u0110\u1ed9ng v\u1eadt) c\u00f3 ph\u01b0\u01a1ng th\u1ee9c <code>eat()<\/code>. C\u00e1c l\u1edbp con nh\u01b0 Dog (Ch\u00f3) v\u00e0 Cat (M\u00e8o) s\u1ebd t\u1ef1 \u0111\u1ed9ng c\u00f3 ph\u01b0\u01a1ng th\u1ee9c <code>eat()<\/code> m\u00e0 kh\u00f4ng c\u1ea7n vi\u1ebft l\u1ea1i.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ L\u1edbp Cha (Superclass)\nclass Animal {\n    public void eat() {\n        System.out.println(\"Animal is eating.\");\n    }\n}\n\n\/\/ L\u1edbp Con (Subclass) k\u1ebf th\u1eeba t\u1eeb Animal\nclass Dog extends Animal {\n    public void bark() {\n        System.out.println(\"Dog is barking: Woof woof!\");\n    }\n}\n\npublic class Main {\n    public static void main(String&#91;] args) {\n        Dog myDog = new Dog();\n        \/\/ Dog c\u00f3 th\u1ec3 g\u1ecdi ph\u01b0\u01a1ng th\u1ee9c c\u1ee7a ch\u00ednh n\u00f3\n        myDog.bark(); \n        \/\/ Dog c\u00f3 th\u1ec3 g\u1ecdi ph\u01b0\u01a1ng th\u1ee9c \u0111\u01b0\u1ee3c k\u1ebf th\u1eeba t\u1eeb Animal\n        myDog.eat(); \n    }\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-tinh-da-hinh-polymorphism\"><strong>T\u00ednh \u0110a h\u00ecnh (Polymorphism)<\/strong><\/h3>\n\n\n\n<p>T\u00ednh \u0110a h\u00ecnh c\u00f3 ngh\u0129a l\u00e0 &#8220;m\u1ed9t t\u00ean, nhi\u1ec1u h\u00ecnh th\u1ee9c&#8221; (Poly &#8211; nhi\u1ec1u, Morph &#8211; h\u00ecnh th\u1ee9c). N\u00f3 cho ph\u00e9p m\u1ed9t h\u00e0nh \u0111\u1ed9ng \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n theo nhi\u1ec1u c\u00e1ch kh\u00e1c nhau, t\u00f9y thu\u1ed9c v\u00e0o \u0111\u1ed1i t\u01b0\u1ee3ng \u0111ang th\u1ef1c hi\u1ec7n h\u00e0nh \u0111\u1ed9ng \u0111\u00f3.<\/p>\n\n\n\n<p><strong>Hai lo\u1ea1i \u0111a h\u00ecnh ch\u00ednh:<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Lo\u1ea1i \u0110a h\u00ecnh<\/strong><\/td><td><strong>X\u1ea3y ra khi&nbsp;<\/strong><\/td><td><strong>\u0110\u1eb7c \u0111i\u1ec3m<\/strong><\/td><td><strong>V\u00ed d\u1ee5&nbsp;<\/strong><\/td><\/tr><tr><td><strong>Overloading (N\u1ea1p ch\u1ed3ng)<\/strong><\/td><td>X\u1ea3y ra trong c\u00f9ng m\u1ed9t L\u1edbp.<\/td><td>C\u00e1c ph\u01b0\u01a1ng th\u1ee9c c\u00f3 c\u00f9ng t\u00ean nh\u01b0ng kh\u00e1c nhau v\u1ec1 s\u1ed1 l\u01b0\u1ee3ng ho\u1eb7c ki\u1ec3u d\u1eef li\u1ec7u c\u1ee7a tham s\u1ed1. Quy\u1ebft \u0111\u1ecbnh \u0111\u01b0\u1ee3c \u0111\u01b0a ra khi bi\u00ean d\u1ecbch (Compile-time).<\/td><td>H\u00e0m <code>add(int a, int b)<\/code> v\u00e0 <code>add(int a, int b, int c)<\/code><\/td><\/tr><tr><td><strong>Overriding (Ghi \u0111\u00e8)<\/strong><\/td><td>X\u1ea3y ra gi\u1eefa L\u1edbp Cha v\u00e0 L\u1edbp Con (y\u00eau c\u1ea7u K\u1ebf th\u1eeba).<\/td><td>L\u1edbp con \u0111\u1ecbnh ngh\u0129a l\u1ea1i m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c \u0111\u00e3 c\u00f3 \u1edf l\u1edbp cha \u0111\u1ec3 thay \u0111\u1ed5i logic x\u1eed l\u00fd. Quy\u1ebft \u0111\u1ecbnh \u0111\u01b0\u1ee3c \u0111\u01b0a ra khi ch\u01b0\u01a1ng tr\u00ecnh ch\u1ea1y (Runtime).<\/td><td>L\u1edbp Dog ghi \u0111\u00e8 ph\u01b0\u01a1ng th\u1ee9c makeSound() c\u1ee7a l\u1edbp Animal.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p><strong>V\u00ed d\u1ee5 c\u00e1ch s\u1eed d\u1ee5ng<\/strong>:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ L\u1edbp Cha\nclass Animal {\n    public void makeSound() {\n        System.out.println(\"Animal makes a generic sound.\");\n    }\n}\n\n\/\/ L\u1edbp Con Ghi \u0111\u00e8 ph\u01b0\u01a1ng th\u1ee9c makeSound()\nclass Cat extends Animal {\n    @Override\n    public void makeSound() {\n        \/\/ Thay \u0111\u1ed5i logic c\u1ee5 th\u1ec3 cho Cat\n        System.out.println(\"Cat says: Meow meow.\");\n    }\n}\n\npublic class Main {\n    public static void main(String&#91;] args) {\n        Animal myCat = new Cat(); \n        \/\/ D\u00f9 bi\u1ebfn l\u00e0 ki\u1ec3u Animal, nh\u01b0ng ph\u01b0\u01a1ng th\u1ee9c c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng Cat \u0111\u01b0\u1ee3c g\u1ecdi (\u0110a h\u00ecnh Runtime)\n        myCat.makeSound(); \/\/ K\u1ebft qu\u1ea3: Cat says: Meow meow.\n    }\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-tinh-tr\u1eebu-t\u01b0\u1ee3ng-abstraction\"><strong>T\u00ednh Tr\u1eebu t\u01b0\u1ee3ng (Abstraction)<\/strong><\/h3>\n\n\n\n<p>T\u00ednh tr\u1eebu t\u01b0\u1ee3ng l\u00e0 kh\u1ea3 n\u0103ng t\u1eadp trung v\u00e0o nh\u1eefng t\u00ednh n\u0103ng t\u1ed5ng qu\u00e1t c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng thay v\u00ec \u0111i s\u00e2u v\u00e0o chi ti\u1ebft c\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng b\u00ean trong (t\u1eadp trung v\u00e0o &#8220;l\u00e0m c\u00e1i g\u00ec&#8221; thay v\u00ec &#8220;l\u00e0m nh\u01b0 th\u1ebf n\u00e0o&#8221;).<\/p>\n\n\n\n<p>C\u01a1 ch\u1ebf ho\u1ea1t \u0111\u1ed9ng<strong>:<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>C\u00f4ng c\u1ee5&nbsp;<\/strong><\/td><td><strong>\u0110\u1eb7c \u0111i\u1ec3m<\/strong><\/td><td><strong>Khi n\u00e0o s\u1eed d\u1ee5ng<\/strong><\/td><\/tr><tr><td><strong>Abstract Class<\/strong><\/td><td>C\u00f3 th\u1ec3 ch\u1ee9a c\u1ea3 ph\u01b0\u01a1ng th\u1ee9c \u0111\u00e3 \u0111\u1ecbnh ngh\u0129a (c\u00f3 th\u00e2n h\u00e0m) v\u00e0 ph\u01b0\u01a1ng th\u1ee9c tr\u1eebu t\u01b0\u1ee3ng (ch\u1ec9 c\u00f3 ch\u1eef k\u00fd).<\/td><td>D\u00f9ng khi c\u00e1c l\u1edbp c\u00f3 quan h\u1ec7 h\u1ecd h\u00e0ng g\u1ea7n g\u0169i (is-a) v\u00e0 mu\u1ed1n chia s\u1ebb chung m\u1ed9t ph\u1ea7n m\u00e3 ngu\u1ed3n.<\/td><\/tr><tr><td><strong>Interface<\/strong><\/td><td>Ch\u1ec9 ch\u1ee9a c\u00e1c ph\u01b0\u01a1ng th\u1ee9c tr\u1eebu t\u01b0\u1ee3ng (trong c\u00e1c phi\u00ean b\u1ea3n Java c\u0169) ho\u1eb7c h\u1eb1ng s\u1ed1. L\u00e0 m\u1ed9t b\u1ea3n cam k\u1ebft v\u1ec1 c\u00e1c h\u00e0nh vi m\u00e0 m\u1ed9t l\u1edbp ph\u1ea3i th\u1ef1c hi\u1ec7n.<\/td><td>D\u00f9ng khi mu\u1ed1n \u0111\u1ecbnh ngh\u0129a m\u1ed9t kh\u1ea3 n\u0103ng (can-do) cho c\u00e1c l\u1edbp kh\u00f4ng nh\u1ea5t thi\u1ebft c\u00f9ng lo\u1ea1i.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>Ph\u00e2n bi\u1ec7t gi\u1eefa Abstract Class v\u00e0 Interface:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Abstract Class: Animal c\u00f3 ph\u01b0\u01a1ng th\u1ee9c \u0111\u00e3 \u0111\u1ecbnh ngh\u0129a sleep() v\u00e0 ph\u01b0\u01a1ng th\u1ee9c tr\u1eebu t\u01b0\u1ee3ng <code>makeSound()<\/code>. T\u1ea5t c\u1ea3 c\u00e1c l\u1edbp con (nh\u01b0 Dog, Cat) \u0111\u1ec1u c\u00f3 th\u1ec3 d\u00f9ng chung <code>sleep()<\/code> nh\u01b0ng b\u1eaft bu\u1ed9c ph\u1ea3i t\u1ef1 \u0111\u1ecbnh ngh\u0129a <code>makeSound()<\/code> ri\u00eang.<\/li>\n\n\n\n<li>Interface: Flyable. C\u1ea3 Bird (Chim) v\u00e0 Airplane (M\u00e1y bay) \u0111\u1ec1u c\u00f3 th\u1ec3 implements (th\u1ef1c thi) Interface n\u00e0y, m\u1eb7c d\u00f9 ch\u00fang kh\u00f4ng h\u1ec1 c\u00f3 quan h\u1ec7 h\u1ecd h\u00e0ng.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-cac-cau-h\u1ecfi-th\u01b0\u1eddng-g\u1eb7p-v\u1ec1-l\u1eadp-trinh-h\u01b0\u1edbng-d\u1ed1i-t\u01b0\u1ee3ng-java\"><span class=\"ez-toc-section\" id=\"Cac_cau_hoi_thuong_gap_ve_lap_trinh_huong_doi_tuong_Java\"><\/span><strong>C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-t\u1ea1i-sao-java-khong-h\u1ed7-tr\u1ee3-da-k\u1ebf-th\u1eeba-t\u1eeb-cac-l\u1edbp-class\"><strong>T\u1ea1i sao Java kh\u00f4ng h\u1ed7 tr\u1ee3 \u0111a k\u1ebf th\u1eeba t\u1eeb c\u00e1c L\u1edbp (Class)?<\/strong><\/h3>\n\n\n\n<p>Trong Java, m\u1ed9t l\u1edbp kh\u00f4ng th\u1ec3 k\u1ebf th\u1eeba tr\u1ef1c ti\u1ebfp t\u1eeb hai hay nhi\u1ec1u l\u1edbp cha (v\u00ed d\u1ee5: <code>class C extends A<\/code>, <code>B<\/code>). \u0110i\u1ec1u n\u00e0y nh\u1eb1m tr\u00e1nh <strong>v\u1ea5n \u0111\u1ec1 kim c\u01b0\u01a1ng (Diamond Problem)<\/strong> \u2013 t\u00ecnh tr\u1ea1ng xung \u0111\u1ed9t khi c\u1ea3 hai l\u1edbp cha c\u00f9ng c\u00f3 m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c tr\u00f9ng t\u00ean nh\u01b0ng kh\u00e1c c\u00e1ch x\u1eed l\u00fd, khi\u1ebfn l\u1edbp con kh\u00f4ng bi\u1ebft n\u00ean s\u1eed d\u1ee5ng ph\u01b0\u01a1ng th\u1ee9c n\u00e0o.<\/p>\n\n\n\n<p><strong>Gi\u1ea3i ph\u00e1p:<\/strong> Java s\u1eed d\u1ee5ng <strong>Interface<\/strong> \u0111\u1ec3 thay th\u1ebf, cho ph\u00e9p m\u1ed9t l\u1edbp c\u00f3 th\u1ec3 th\u1ef1c thi (implement) nhi\u1ec1u Interface c\u00f9ng l\u00fac.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-overloading-va-overriding-khac-nhau-nh\u01b0-th\u1ebf-nao\"><strong>Overloading v\u00e0 Overriding kh\u00e1c nhau nh\u01b0 th\u1ebf n\u00e0o?<\/strong><\/h3>\n\n\n\n<p>\u0110\u00e2y l\u00e0 hai kh\u00e1i ni\u1ec7m d\u1ec5 g\u00e2y nh\u1ea7m l\u1eabn trong t\u00ednh \u0110a h\u00ecnh:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Overloading (N\u1ea1p ch\u1ed3ng):<\/strong> X\u1ea3y ra trong c\u00f9ng m\u1ed9t l\u1edbp. C\u00e1c h\u00e0m c\u00f3 c\u00f9ng t\u00ean nh\u01b0ng kh\u00e1c nhau v\u1ec1 tham s\u1ed1 (s\u1ed1 l\u01b0\u1ee3ng ho\u1eb7c ki\u1ec3u d\u1eef li\u1ec7u). K\u1ebft qu\u1ea3 \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh khi bi\u00ean d\u1ecbch (Compile-time).<\/li>\n\n\n\n<li><strong>Overriding (Ghi \u0111\u00e8):<\/strong> X\u1ea3y ra gi\u1eefa l\u1edbp cha v\u00e0 l\u1edbp con. L\u1edbp con vi\u1ebft l\u1ea1i ph\u01b0\u01a1ng th\u1ee9c c\u1ee7a l\u1edbp cha \u0111\u1ec3 thay \u0111\u1ed5i logic x\u1eed l\u00fd. K\u1ebft qu\u1ea3 \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh khi ch\u01b0\u01a1ng tr\u00ecnh ch\u1ea1y (Runtime).<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-khi-nao-nen-dung-abstract-class-khi-nao-nen-dung-interface\"><strong>Khi n\u00e0o n\u00ean d\u00f9ng Abstract Class, khi n\u00e0o n\u00ean d\u00f9ng Interface?<\/strong><\/h3>\n\n\n\n<p>Vi\u1ec7c l\u1ef1a ch\u1ecdn ph\u1ee5 thu\u1ed9c v\u00e0o m\u1ee5c \u0111\u00edch thi\u1ebft k\u1ebf:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>D\u00f9ng Abstract Class:<\/strong> Khi b\u1ea1n mu\u1ed1n chia s\u1ebb m\u00e3 ngu\u1ed3n gi\u1eefa c\u00e1c l\u1edbp c\u00f3 li\u00ean quan m\u1eadt thi\u1ebft (quan h\u1ec7 &#8220;l\u00e0 m\u1ed9t&#8221; &#8211; is a). V\u00ed d\u1ee5: Circle v\u00e0 Square \u0111\u1ec1u l\u00e0 Shape.<\/li>\n\n\n\n<li><strong>D\u00f9ng Interface:<\/strong> Khi b\u1ea1n mu\u1ed1n \u0111\u1ecbnh ngh\u0129a m\u1ed9t kh\u1ea3 n\u0103ng ho\u1eb7c h\u00e0nh \u0111\u1ed9ng cho c\u00e1c l\u1edbp kh\u00f4ng nh\u1ea5t thi\u1ebft ph\u1ea3i c\u00f9ng lo\u1ea1i (quan h\u1ec7 &#8220;c\u00f3 th\u1ec3 l\u00e0m g\u00ec&#8221; &#8211; can do). V\u00ed d\u1ee5: C\u1ea3 MayBay v\u00e0 Chim \u0111\u1ec1u c\u00f3 th\u1ec3 Flyable.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-khai-ni\u1ec7m-oop-trong-java-co-khac-bi\u1ec7t-nhi\u1ec1u-so-v\u1edbi-python-khong\"><strong>Kh\u00e1i ni\u1ec7m OOP trong Java c\u00f3 kh\u00e1c bi\u1ec7t nhi\u1ec1u so v\u1edbi Python kh\u00f4ng?<\/strong><\/h3>\n\n\n\n<p>D\u00f9 Java v\u00e0 Python \u0111\u1ec1u h\u1ed7 tr\u1ee3 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng, nh\u01b0ng c\u00e1ch ti\u1ebfp c\u1eadn c\u00f3 m\u1ed9t s\u1ed1 \u0111i\u1ec3m kh\u00e1c bi\u1ec7t \u0111\u00e1ng ch\u00fa \u00fd:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>Ti\u00eau ch\u00ed<\/td><td>Java<\/td><td>Python<\/td><\/tr><tr><td>Tri\u1ebft l\u00fd thi\u1ebft k\u1ebf<\/td><td>B\u1eaft bu\u1ed9c (Strict): M\u1ecdi d\u00f2ng code ph\u1ea3i n\u1eb1m trong m\u1ed9t Class. Java \u00e9p ng\u01b0\u1eddi d\u00f9ng theo OOP ngay t\u1eeb \u0111\u1ea7u.<\/td><td>T\u00f9y ch\u1ecdn (Flexible): H\u1ed7 tr\u1ee3 \u0111a m\u00f4 h\u00ecnh. B\u1ea1n c\u00f3 th\u1ec3 vi\u1ebft h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng, h\u01b0\u1edbng ch\u1ee9c n\u0103ng ho\u1eb7c h\u01b0\u1edbng th\u1ee7 t\u1ee5c.<\/td><\/tr><tr><td>Ki\u1ec3u d\u1eef li\u1ec7u (Typing)<\/td><td>Static Typing: Ph\u1ea3i khai b\u00e1o ki\u1ec3u d\u1eef li\u1ec7u r\u00f5 r\u00e0ng (v\u00ed d\u1ee5: <code>Car myCar = new Car()<\/code>). Ki\u1ec3m tra l\u1ed7i ngay khi bi\u00ean d\u1ecbch.<\/td><td>Dynamic Typing: Kh\u00f4ng c\u1ea7n khai b\u00e1o ki\u1ec3u (v\u00ed d\u1ee5: <code>my_car = Car()<\/code>). Ki\u1ec3u d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh khi ch\u01b0\u01a1ng tr\u00ecnh \u0111ang ch\u1ea1y.<\/td><\/tr><tr><td>T\u00ednh \u0111\u00f3ng g\u00f3i (Encapsulation)<\/td><td>Nghi\u00eam ng\u1eb7t: D\u00f9ng <code>private<\/code>, <code>protected<\/code>, <code>public<\/code> \u0111\u1ec3 th\u1ef1c s\u1ef1 ng\u0103n ch\u1eb7n truy c\u1eadp tr\u00e1i ph\u00e9p t\u1eeb b\u00ean ngo\u00e0i.<\/td><td>D\u1ef1a tr\u00ean quy \u01b0\u1edbc: Kh\u00f4ng c\u00f3 r\u00e0o c\u1ea3n v\u1eadt l\u00fd. D\u00f9ng d\u1ea5u g\u1ea1ch d\u01b0\u1edbi (v\u00ed d\u1ee5: <code>_attr<\/code>) \u0111\u1ec3 nh\u1eafc nh\u1edf l\u1eadp tr\u00ecnh vi\u00ean kh\u00f4ng n\u00ean ch\u1ea1m v\u00e0o.<\/td><\/tr><tr><td>\u0110a k\u1ebf th\u1eeba (Multiple Inheritance)<\/td><td>Kh\u00f4ng h\u1ed7 tr\u1ee3 tr\u1ef1c ti\u1ebfp: M\u1ed9t l\u1edbp ch\u1ec9 c\u00f3 1 cha. Gi\u1ea3i quy\u1ebft b\u1eb1ng c\u00e1ch cho ph\u00e9p tri\u1ec3n khai (implement) nhi\u1ec1u Interface.<\/td><td>H\u1ed7 tr\u1ee3 tr\u1ef1c ti\u1ebfp: M\u1ed9t l\u1edbp c\u00f3 th\u1ec3 k\u1ebf th\u1eeba t\u1eeb nhi\u1ec1u l\u1edbp cha c\u00f9ng l\u00fac. S\u1eed d\u1ee5ng thu\u1eadt to\u00e1n MRO \u0111\u1ec3 x\u1eed l\u00fd xung \u0111\u1ed9t.<\/td><\/tr><tr><td>H\u00e0m kh\u1edfi t\u1ea1o (Constructor)<\/td><td>S\u1eed d\u1ee5ng ph\u01b0\u01a1ng th\u1ee9c tr\u00f9ng t\u00ean v\u1edbi Class (v\u00ed d\u1ee5: public <code>ClassName()<\/code>).<\/td><td>S\u1eed d\u1ee5ng ph\u01b0\u01a1ng th\u1ee9c \u0111\u1eb7c bi\u1ec7t \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a s\u1eb5n l\u00e0 <code>def __init__(self):<\/code>.<\/td><\/tr><tr><td>T\u1eeb kh\u00f3a tham chi\u1ebfu<\/td><td>S\u1eed d\u1ee5ng t\u1eeb kh\u00f3a this \u0111\u1ec3 tham chi\u1ebfu \u0111\u1ebfn \u0111\u1ed1i t\u01b0\u1ee3ng hi\u1ec7n t\u1ea1i.<\/td><td>S\u1eed d\u1ee5ng t\u1eeb kh\u00f3a self (ph\u1ea3i khai b\u00e1o t\u01b0\u1eddng minh l\u00e0m tham s\u1ed1 \u0111\u1ea7u ti\u00ean trong ph\u01b0\u01a1ng th\u1ee9c).<\/td><\/tr><tr><td>Interface<\/td><td>C\u00f3 t\u1eeb kh\u00f3a interface ri\u00eang bi\u1ec7t \u0111\u1ec3 \u0111\u1ecbnh ngh\u0129a c\u00e1c b\u1ea3n cam k\u1ebft h\u00e0nh vi.<\/td><td>Kh\u00f4ng c\u00f3 t\u1eeb kh\u00f3a interface. Th\u01b0\u1eddng s\u1eed d\u1ee5ng c\u00e1c l\u1edbp c\u01a1 s\u1edf tr\u1eebu t\u01b0\u1ee3ng (Abstract Base Classes) \u0111\u1ec3 thay th\u1ebf.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-k\u1ebft-lu\u1eadn\"><span class=\"ez-toc-section\" id=\"Ket_luan\"><\/span><strong>K\u1ebft lu\u1eadn<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java kh\u00f4ng ch\u1ec9 l\u00e0 vi\u1ec7c h\u1ecdc c\u00e1c c\u00fa ph\u00e1p hay t\u1eeb kh\u00f3a, m\u00e0 l\u00e0 vi\u1ec7c thay \u0111\u1ed5i t\u01b0 duy t\u1eeb gi\u1ea3i quy\u1ebft c\u00e1c b\u01b0\u1edbc c\u00f4ng vi\u1ec7c sang qu\u1ea3n l\u00fd v\u00e0 t\u01b0\u01a1ng t\u00e1c gi\u1eefa c\u00e1c th\u1ef1c th\u1ec3. Vi\u1ec7c n\u1eafm v\u1eefng b\u1ed1n c\u1ed9t tr\u1ee5: \u0110\u00f3ng g\u00f3i, K\u1ebf th\u1eeba, \u0110a h\u00ecnh v\u00e0 Tr\u1eebu t\u01b0\u1ee3ng s\u1ebd gi\u00fap b\u1ea1n x\u00e2y d\u1ef1ng \u0111\u01b0\u1ee3c nh\u1eefng h\u1ec7 th\u1ed1ng ph\u1ea7n m\u1ec1m c\u00f3 c\u1ea5u tr\u00fac ch\u1eb7t ch\u1ebd, an to\u00e0n v\u00e0 d\u1ec5 d\u00e0ng m\u1edf r\u1ed9ng.<\/p>\n\n\n\n<p>D\u00f9 c\u00e1c ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh m\u1edbi li\u00ean t\u1ee5c xu\u1ea5t hi\u1ec7n, t\u01b0 duy OOP v\u1eabn l\u00e0 n\u1ec1n t\u1ea3ng quan tr\u1ecdng gi\u00fap l\u1eadp tr\u00ecnh vi\u00ean th\u00edch nghi nhanh ch\u00f3ng v\u1edbi m\u1ecdi c\u00f4ng ngh\u1ec7. Khi \u0111\u00e3 hi\u1ec3u r\u00f5 c\u00e1ch v\u1eadn h\u00e0nh c\u1ee7a L\u1edbp v\u00e0 \u0110\u1ed1i t\u01b0\u1ee3ng, b\u1ea1n \u0111\u00e3 s\u1eb5n s\u00e0ng \u0111\u1ec3 ti\u1ebfn xa h\u01a1n v\u00e0o c\u00e1c ch\u1ee7 \u0111\u1ec1 n\u00e2ng cao nh\u01b0 Design Patterns hay ki\u1ebfn tr\u00fac h\u1ec7 th\u1ed1ng chuy\u00ean nghi\u1ec7p.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Java \u0111\u01b0\u1ee3c xem l\u00e0 ng\u00f4n ng\u1eef \u0111\u1ea1i di\u1ec7n ti\u00eau bi\u1ec3u nh\u1ea5t cho OOP v\u00ec m\u1ecdi th\u00e0nh ph\u1ea7n trong Java \u0111\u1ec1u \u0111\u01b0\u1ee3c x\u00e2y d\u1ef1ng d\u1ef1a tr\u00ean c\u00e1c l\u1edbp v\u00e0 \u0111\u1ed1i t\u01b0\u1ee3ng. Vi\u1ec7c \u00e1p d\u1ee5ng l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng trong Java gi\u00fap b\u1ea1n t\u1ed1i \u01b0u h\u00f3a kh\u1ea3 n\u0103ng t\u00e1i s\u1eed d\u1ee5ng code, khi\u1ebfn h\u1ec7 th\u1ed1ng tr\u1edf [&hellip;]<\/p>\n","protected":false},"author":203,"featured_media":95535,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_gspb_post_css":"","footnotes":""},"categories":[109,10350],"tags":[],"class_list":["post-94491","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-chuyen-mon-it","category-java"],"blocksy_meta":[],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v26.8 (Yoast SEO v27.7) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java: Gi\u1ea3i th\u00edch chi ti\u1ebft k\u00e8m v\u00ed d\u1ee5 - ITviec Blog<\/title>\n<meta name=\"description\" content=\"Hi\u1ec3u c\u1eb7n k\u1ebd v\u1ec1 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java k\u00e8m v\u00ed d\u1ee5: chi ti\u1ebft v\u1ec1 class, object c\u00f9ng 4 t\u00ednh ch\u1ea5t tr\u1ee5 c\u1ed9t c\u1ee7a OOP trong Java.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/itviec.com\/blog\/lap-trinh-huong-doi-trong-java\/\" \/>\n<meta property=\"og:locale\" content=\"vi_VN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng Java: Gi\u1ea3i th\u00edch chi ti\u1ebft k\u00e8m v\u00ed d\u1ee5\" \/>\n<meta property=\"og:description\" content=\"Java \u0111\u01b0\u1ee3c xem l\u00e0 ng\u00f4n ng\u1eef \u0111\u1ea1i di\u1ec7n ti\u00eau bi\u1ec3u nh\u1ea5t cho OOP v\u00ec m\u1ecdi th\u00e0nh ph\u1ea7n trong Java \u0111\u1ec1u \u0111\u01b0\u1ee3c x\u00e2y d\u1ef1ng d\u1ef1a tr\u00ean c\u00e1c l\u1edbp v\u00e0 \u0111\u1ed1i t\u01b0\u1ee3ng. 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