{"id":33362,"date":"2025-09-24T10:41:13","date_gmt":"2025-09-24T03:41:13","guid":{"rendered":"https:\/\/interdata.vn\/blog\/?p=33362"},"modified":"2025-09-24T10:42:58","modified_gmt":"2025-09-24T03:42:58","slug":"encapsulation-la-gi","status":"publish","type":"post","link":"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/","title":{"rendered":"Encapsulation l\u00e0 g\u00ec? Vai tr\u00f2 &#038; \u1ee8ng d\u1ee5ng t\u00ednh \u0111\u00f3ng g\u00f3i [OOP]"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-white ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">N\u1ed8I DUNG<\/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 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Encapsulation-la-gi\" >Encapsulation l\u00e0 g\u00ec?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Vi-du-thuc-te-ve-Encapsulation-Chiec-ket-sat\" >V\u00ed d\u1ee5 th\u1ef1c t\u1ebf v\u1ec1 Encapsulation: Chi\u1ebfc k\u00e9t s\u1eaft<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Encapsulation-trong-Lap-trinh-Lop-Account\" >Encapsulation trong L\u1eadp tr\u00ecnh: L\u1edbp Account<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Vi-sao-Encapsulation-trong-OOP-lai-quan-trong\" >V\u00ec sao Encapsulation trong OOP l\u1ea1i quan tr\u1ecdng?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Che-giau-du-lieu-Data-Hiding-va-Tinh-bao-mat\" >Che gi\u1ea5u d\u1eef li\u1ec7u (Data Hiding) v\u00e0 T\u00ednh b\u1ea3o m\u1eadt<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Bao-toan-tinh-toan-ven-du-lieu-Data-Integrity\" >B\u1ea3o to\u00e0n t\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u (Data Integrity)<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#De-dang-bao-tri-va-mo-rong-code\" >D\u1ec5 d\u00e0ng b\u1ea3o tr\u00ec v\u00e0 m\u1edf r\u1ed9ng code<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Cach-thuc-hoat-dong-cua-Encapsulation-Getter-va-Setter\" >C\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng c\u1ee7a Encapsulation: Getter v\u00e0 Setter<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Phan-biet-Encapsulation-va-Abstraction\" >Ph\u00e2n bi\u1ec7t Encapsulation v\u00e0 Abstraction<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Vi-du-thuc-te-ve-Encapsulation-trong-cac-ngon-ngu-lap-trinh-pho-bien\" >V\u00ed d\u1ee5 th\u1ef1c t\u1ebf v\u1ec1 Encapsulation trong c\u00e1c ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh ph\u1ed5 bi\u1ebfn<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Encapsulation-trong-Java\" >Encapsulation trong Java<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Encapsulation-trong-Python\" >Encapsulation trong Python<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Loi-khuyen-khi-su-dung-Encapsulation\" >L\u1eddi khuy\u00ean khi s\u1eed d\u1ee5ng Encapsulation<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Cac-cau-hoi-thuong-gap-ve-Encapsulation\" >C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 Encapsulation<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Encapsulation-la-gi-2\" >Encapsulation l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Tai-sao-can-su-dung-tinh-dong-goi\" >T\u1ea1i sao c\u1ea7n s\u1eed d\u1ee5ng t\u00ednh \u0111\u00f3ng g\u00f3i?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Lam-cach-nao-de-thuc-hien-tinh-dong-goi-trong-lap-trinh\" >L\u00e0m c\u00e1ch n\u00e0o \u0111\u1ec3 th\u1ef1c hi\u1ec7n t\u00ednh \u0111\u00f3ng g\u00f3i trong l\u1eadp tr\u00ecnh?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Encapsulation-co-phai-la-che-giau-du-lieu-khong\" >Encapsulation c\u00f3 ph\u1ea3i l\u00e0 che gi\u1ea5u d\u1eef li\u1ec7u kh\u00f4ng?<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-19\" href=\"https:\/\/interdata.vn\/blog\/encapsulation-la-gi\/#Ket-luan\" >K\u1ebft lu\u1eadn<\/a><\/li><\/ul><\/nav><\/div>\n<p>M\u1ed9t trong b\u1ed1n tr\u1ee5 c\u1ed9t c\u1ee7a l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng (OOP), <strong>Encapsulation hay t\u00ednh \u0111\u00f3ng g\u00f3i<\/strong> \u0111\u00f3ng vai tr\u00f2 then ch\u1ed1t trong vi\u1ec7c x\u00e2y d\u1ef1ng ph\u1ea7n m\u1ec1m an to\u00e0n, d\u1ec5 b\u1ea3o tr\u00ec. N\u1ebfu b\u1ea1n \u0111ang b\u0103n kho\u0103n v\u1ec1 kh\u00e1i ni\u1ec7m n\u00e0y, b\u00e0i vi\u1ebft s\u1ebd gi\u00fap b\u1ea1n n\u1eafm v\u1eefng t\u1eeb A-Z. Ch\u00fang ta s\u1ebd c\u00f9ng nhau t\u00ecm hi\u1ec3u \u0111\u1ecbnh ngh\u0129a <strong>Encapsulation l\u00e0 g\u00ec<\/strong>, t\u1ea7m quan tr\u1ecdng, c\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng qua c\u00e1c v\u00ed d\u1ee5 th\u1ef1c t\u1ebf, v\u00e0 c\u1ea3 c\u00e1ch ph\u00e2n bi\u1ec7t n\u00f3 v\u1edbi Abstraction &#8211; kh\u00e1i ni\u1ec7m th\u01b0\u1eddng b\u1ecb nh\u1ea7m l\u1eabn.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Encapsulation-la-gi\"><\/span>Encapsulation l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Trong l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng (OOP), <strong>Encapsulation<\/strong> l\u00e0 qu\u00e1 tr\u00ecnh g\u00f3i g\u1ecdn <strong>d\u1eef li\u1ec7u<\/strong> (thu\u1ed9c t\u00ednh) v\u00e0 <strong>ph\u01b0\u01a1ng th\u1ee9c<\/strong> (h\u00e0nh vi) li\u00ean quan \u0111\u1ebfn d\u1eef li\u1ec7u \u0111\u00f3 v\u00e0o chung m\u1ed9t \u0111\u01a1n v\u1ecb duy nh\u1ea5t, th\u01b0\u1eddng l\u00e0 m\u1ed9t <strong>l\u1edbp (class)<\/strong>. M\u1ee5c \u0111\u00edch ch\u00ednh l\u00e0 \u0111\u1ec3 <strong>che gi\u1ea5u d\u1eef li\u1ec7u<\/strong> b\u00ean trong v\u00e0 ch\u1ec9 cho ph\u00e9p truy c\u1eadp th\u00f4ng qua c\u00e1c ph\u01b0\u01a1ng th\u1ee9c c\u00f4ng khai \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a s\u1eb5n.<\/p>\n<p>B\u1ea1n c\u00f3 th\u1ec3 ngh\u0129 v\u1ec1 n\u00f3 nh\u01b0 m\u1ed9t &#8220;h\u1ed9p \u0111en&#8221; v\u1edbi c\u00e1c n\u00fat b\u1ea5m b\u00ean ngo\u00e0i. B\u1ea1n ch\u1ec9 c\u1ea7n bi\u1ebft c\u00e1ch s\u1eed d\u1ee5ng c\u00e1c n\u00fat b\u1ea5m n\u00e0y (c\u00e1c ph\u01b0\u01a1ng th\u1ee9c c\u00f4ng khai) \u0111\u1ec3 \u0111i\u1ec1u khi\u1ec3n &#8220;h\u1ed9p \u0111en&#8221; \u0111\u00f3, m\u00e0 kh\u00f4ng c\u1ea7n b\u1eadn t\u00e2m \u0111\u1ebfn c\u1ea5u tr\u00fac ph\u1ee9c t\u1ea1p b\u00ean trong. \u0110i\u1ec1u n\u00e0y gi\u00fap b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u kh\u1ecfi vi\u1ec7c b\u1ecb can thi\u1ec7p tr\u1ef1c ti\u1ebfp t\u1eeb b\u00ean ngo\u00e0i, \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n v\u00e0 an to\u00e0n cho ch\u01b0\u01a1ng tr\u00ecnh.<\/p>\n<figure id=\"attachment_33365\" aria-describedby=\"caption-attachment-33365\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-33365\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-la-gi.jpg\" alt=\"Encapsulation l\u00e0 g\u00ec\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-la-gi.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-la-gi-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-la-gi-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-33365\" class=\"wp-caption-text\">Encapsulation l\u00e0 g\u00ec<\/figcaption><\/figure>\n<h3><span class=\"ez-toc-section\" id=\"Vi-du-thuc-te-ve-Encapsulation-Chiec-ket-sat\"><\/span>V\u00ed d\u1ee5 th\u1ef1c t\u1ebf v\u1ec1 Encapsulation: Chi\u1ebfc k\u00e9t s\u1eaft<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u1ec3 d\u1ec5 h\u00ecnh dung h\u01a1n, h\u00e3y xem x\u00e9t m\u1ed9t chi\u1ebfc k\u00e9t s\u1eaft. Chi\u1ebfc k\u00e9t s\u1eaft n\u00e0y ch\u00ednh l\u00e0 m\u1ed9t <code>\u0111\u1ed1i t\u01b0\u1ee3ng<\/code> (Object).<\/p>\n<ul>\n<li><strong>D\u1eef li\u1ec7u b\u00ean trong<\/strong> l\u00e0 t\u00e0i s\u1ea3n c\u1ee7a b\u1ea1n: ti\u1ec1n m\u1eb7t, gi\u1ea5y t\u1edd quan tr\u1ecdng.<\/li>\n<li><strong>C\u00e1c ph\u01b0\u01a1ng th\u1ee9c<\/strong> l\u00e0 h\u00e0nh \u0111\u1ed9ng b\u1ea1n c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n: m\u1edf kh\u00f3a b\u1eb1ng m\u1eadt m\u00e3, kh\u00f3a l\u1ea1i.<\/li>\n<\/ul>\n<p>Chi\u1ebfc k\u00e9t s\u1eaft \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1ec3 b\u1ea1n kh\u00f4ng th\u1ec3 l\u1ea5y t\u00e0i s\u1ea3n b\u00ean trong m\u00e0 kh\u00f4ng qua c\u00e1nh c\u1eeda v\u00e0 s\u1eed d\u1ee5ng \u0111\u00fang m\u1eadt m\u00e3. B\u1ea1n kh\u00f4ng th\u1ec3 khoan th\u1ee7ng t\u1eeb b\u00ean ngo\u00e0i \u0111\u1ec3 l\u1ea5y ti\u1ec1n, v\u00ec nh\u01b0 v\u1eady s\u1ebd l\u00e0m h\u01b0 h\u1ea1i t\u00e0i s\u1ea3n. T\u01b0\u01a1ng t\u1ef1, <strong>Encapsulation<\/strong> ng\u0103n c\u1ea3n vi\u1ec7c &#8220;\u0111\u1ee5c&#8221; th\u1eb3ng v\u00e0o d\u1eef li\u1ec7u c\u1ee7a m\u1ed9t \u0111\u1ed1i t\u01b0\u1ee3ng. N\u00f3 ch\u1ec9 cho ph\u00e9p b\u1ea1n t\u01b0\u01a1ng t\u00e1c v\u1edbi d\u1eef li\u1ec7u th\u00f4ng qua c\u00e1c &#8220;c\u00e1nh c\u1eeda&#8221; \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a tr\u01b0\u1edbc (c\u00e1c ph\u01b0\u01a1ng th\u1ee9c c\u00f4ng khai).<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Encapsulation-trong-Lap-trinh-Lop-Account\"><\/span>Encapsulation trong L\u1eadp tr\u00ecnh: L\u1edbp <code>Account<\/code><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>H\u00e3y xem m\u1ed9t v\u00ed d\u1ee5 l\u1eadp tr\u00ecnh c\u1ee5 th\u1ec3 h\u01a1n v\u1edbi m\u1ed9t l\u1edbp <code>Account<\/code> (T\u00e0i kho\u1ea3n ng\u00e2n h\u00e0ng) trong Java.<\/p>\n<pre><code>public class Account {\r\n    private <a href=\"https:\/\/interdata.vn\/blog\/string-la-gi\/\">String<\/a> accountNumber;\r\n    private double balance;\r\n\r\n    public Account(String accountNumber, double balance) {\r\n        this.accountNumber = accountNumber;\r\n        this.balance = balance;\r\n    }\r\n}\r\n<\/code><\/pre>\n<p>\u1ede \u0111\u00e2y, <code>accountNumber<\/code> v\u00e0 <code>balance<\/code> l\u00e0 hai thu\u1ed9c t\u00ednh. V\u1edbi \u0111\u1ecbnh ngh\u0129a \u0111\u01a1n gi\u1ea3n n\u00e0y, b\u1ea5t k\u1ef3 \u0111o\u1ea1n code n\u00e0o c\u0169ng c\u00f3 th\u1ec3 truy c\u1eadp v\u00e0 thay \u0111\u1ed5i gi\u00e1 tr\u1ecb c\u1ee7a ch\u00fang. V\u00ed d\u1ee5:<\/p>\n<pre><code>Account myAccount = new Account(\"123456\", 1000);\r\nmyAccount.balance = -500; \/\/ L\u1ed7i nghi\u00eam tr\u1ecdng!\r\n<\/code><\/pre>\n<p>\u0110\u00e2y l\u00e0 m\u1ed9t v\u1ea5n \u0111\u1ec1 l\u1edbn v\u00ec n\u00f3 c\u00f3 th\u1ec3 d\u1eabn \u0111\u1ebfn c\u00e1c l\u1ed7i logic v\u00e0 b\u1ea3o m\u1eadt. \u0110\u1ec3 gi\u1ea3i quy\u1ebft, ch\u00fang ta s\u1eed d\u1ee5ng <strong>Encapsulation<\/strong> b\u1eb1ng c\u00e1ch khai b\u00e1o c\u00e1c thu\u1ed9c t\u00ednh n\u00e0y l\u00e0 <code>private<\/code> v\u00e0 cung c\u1ea5p c\u00e1c ph\u01b0\u01a1ng th\u1ee9c c\u00f4ng khai (<code>public<\/code>) \u0111\u1ec3 ki\u1ec3m so\u00e1t vi\u1ec7c truy c\u1eadp.<\/p>\n<pre><code>public class Account {\r\n    private String accountNumber;\r\n    private double balance;\r\n\r\n    public Account(String accountNumber, double balance) {\r\n        this.accountNumber = accountNumber;\r\n        this.balance = balance;\r\n    }\r\n\r\n    \/\/ Ph\u01b0\u01a1ng th\u1ee9c Getter \u0111\u1ec3 l\u1ea5y s\u1ed1 d\u01b0\r\n    public double getBalance() {\r\n        return this.balance;\r\n    }\r\n\r\n    \/\/ Ph\u01b0\u01a1ng th\u1ee9c Setter \u0111\u1ec3 n\u1ea1p ti\u1ec1n\r\n    public void deposit(double amount) {\r\n        if (amount &gt; 0) {\r\n            this.balance += amount;\r\n        }\r\n    }\r\n}\r\n<\/code><\/pre>\n<p>V\u1edbi phi\u00ean b\u1ea3n code \u0111\u00e3 \u0111\u00f3ng g\u00f3i, vi\u1ec7c truy c\u1eadp tr\u1ef1c ti\u1ebfp v\u00e0o <code>balance<\/code> \u0111\u00e3 kh\u00f4ng th\u1ec3. B\u1ea1n ch\u1ec9 c\u00f3 th\u1ec3 t\u01b0\u01a1ng t\u00e1c v\u1edbi n\u00f3 th\u00f4ng qua c\u00e1c ph\u01b0\u01a1ng th\u1ee9c <code>getBalance()<\/code> v\u00e0 <code>deposit()<\/code>. Vi\u1ec7c n\u00e0y gi\u00fap ng\u0103n ch\u1eb7n c\u00e1c thay \u0111\u1ed5i kh\u00f4ng h\u1ee3p l\u1ec7, \u0111\u1ea3m b\u1ea3o d\u1eef li\u1ec7u lu\u00f4n h\u1ee3p l\u00fd.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Vi-sao-Encapsulation-trong-OOP-lai-quan-trong\"><\/span>V\u00ec sao Encapsulation trong OOP l\u1ea1i quan tr\u1ecdng?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Encapsulation kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t kh\u00e1i ni\u1ec7m l\u00fd thuy\u1ebft, n\u00f3 l\u00e0 nguy\u00ean t\u1eafc c\u01a1 b\u1ea3n \u0111\u1ec3 x\u00e2y d\u1ef1ng c\u00e1c h\u1ec7 th\u1ed1ng ph\u1ea7n m\u1ec1m m\u1ea1nh m\u1ebd v\u00e0 \u0111\u00e1ng tin c\u1eady. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 nh\u1eefng l\u1ee3i \u00edch c\u1ed1t l\u00f5i m\u00e0 t\u00ednh \u0111\u00f3ng g\u00f3i mang l\u1ea1i.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Che-giau-du-lieu-Data-Hiding-va-Tinh-bao-mat\"><\/span>Che gi\u1ea5u d\u1eef li\u1ec7u (Data Hiding) v\u00e0 T\u00ednh b\u1ea3o m\u1eadt<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00e2y l\u00e0 l\u1ee3i \u00edch quan tr\u1ecdng nh\u1ea5t c\u1ee7a Encapsulation. B\u1eb1ng c\u00e1ch khai b\u00e1o d\u1eef li\u1ec7u l\u00e0 <code>private<\/code>, ch\u00fang ta ng\u0103n c\u1ea3n vi\u1ec7c truy c\u1eadp tr\u1ef1c ti\u1ebfp t\u1eeb b\u00ean ngo\u00e0i l\u1edbp.<\/p>\n<ul>\n<li><strong>Kh\u00f4ng c\u00f3 Encapsulation:<\/strong> D\u1eef li\u1ec7u b\u1ecb &#8220;ph\u01a1i b\u00e0y&#8221; v\u00e0 c\u00f3 th\u1ec3 b\u1ecb thay \u0111\u1ed5i b\u1edfi b\u1ea5t k\u1ef3 ph\u1ea7n code n\u00e0o. \u0110i\u1ec1u n\u00e0y gi\u1ed1ng nh\u01b0 vi\u1ec7c \u0111\u1ec3 k\u00e9t s\u1eaft m\u1edf, ai c\u0169ng c\u00f3 th\u1ec3 t\u00f9y \u00fd l\u1ea5y ho\u1eb7c th\u00eam \u0111\u1ed3 v\u00e0o.<\/li>\n<li><strong>C\u00f3 Encapsulation:<\/strong> D\u1eef li\u1ec7u \u0111\u01b0\u1ee3c che gi\u1ea5u b\u00ean trong l\u1edbp. C\u00e1c ph\u01b0\u01a1ng th\u1ee9c c\u00f4ng khai \u0111\u00f3ng vai tr\u00f2 l\u00e0 &#8220;ng\u01b0\u1eddi b\u1ea3o v\u1ec7&#8221;, ki\u1ec3m so\u00e1t m\u1ecdi h\u00e0nh \u0111\u1ed9ng t\u01b0\u01a1ng t\u00e1c v\u1edbi d\u1eef li\u1ec7u. \u0110i\u1ec1u n\u00e0y gi\u00fap b\u1ea3o v\u1ec7 gi\u00e1 tr\u1ecb kh\u1ecfi b\u1ecb thay \u0111\u1ed5i ng\u1eabu nhi\u00ean, d\u1eabn \u0111\u1ebfn c\u00e1c l\u1ed7i kh\u00f3 l\u01b0\u1eddng.<\/li>\n<\/ul>\n<p>H\u00e3y xem x\u00e9t m\u1ed9t v\u00ed d\u1ee5 th\u1ef1c t\u1ebf v\u1ec1 b\u1ea3o m\u1eadt v\u1edbi m\u1ed9t l\u1edbp <code>User<\/code>.<\/p>\n<pre><code>public class User {\r\n    private String username;\r\n    private String password;\r\n    private int loginAttempts;\r\n\r\n    \/\/ C\u00e1c ph\u01b0\u01a1ng th\u1ee9c getter\/setter v\u00e0 business logic\r\n}\r\n<\/code><\/pre>\n<p>Khi b\u1ea1n \u0111\u0103ng nh\u1eadp v\u00e0o m\u1ed9t trang web, b\u1ea1n s\u1ebd t\u01b0\u01a1ng t\u00e1c v\u1edbi m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c <code>login()<\/code>. Ph\u01b0\u01a1ng th\u1ee9c n\u00e0y s\u1ebd ki\u1ec3m tra <code>username<\/code> v\u00e0 <code>password<\/code> b\u1ea1n nh\u1eadp v\u00e0o. D\u1eef li\u1ec7u <code>password<\/code> \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7 b\u00ean trong l\u1edbp, v\u00e0 b\u1ea1n kh\u00f4ng th\u1ec3 tr\u1ef1c ti\u1ebfp truy c\u1eadp ho\u1eb7c thay \u0111\u1ed5i <strong>n\u00f3<\/strong>. Vi\u1ec7c n\u00e0y ng\u0103n ch\u1eb7n c\u00e1c h\u00e0nh vi gian l\u1eadn ho\u1eb7c thay \u0111\u1ed5i th\u00f4ng tin tr\u00e1i ph\u00e9p.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Bao-toan-tinh-toan-ven-du-lieu-Data-Integrity\"><\/span>B\u1ea3o to\u00e0n t\u00ednh to\u00e0n v\u1eb9n d\u1eef li\u1ec7u (Data Integrity)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Khi d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7, ch\u00fang ta c\u00f3 th\u1ec3 ki\u1ec3m so\u00e1t ho\u00e0n to\u00e0n c\u00e1ch th\u1ee9c n\u00f3 \u0111\u01b0\u1ee3c thay \u0111\u1ed5i. M\u1ed9t trong nh\u1eefng nhi\u1ec7m v\u1ee5 c\u1ee7a Encapsulation l\u00e0 \u0111\u1ea3m b\u1ea3o r\u1eb1ng c\u00e1c thu\u1ed9c t\u00ednh c\u1ee7a m\u1ed9t \u0111\u1ed1i t\u01b0\u1ee3ng lu\u00f4n n\u1eb1m trong m\u1ed9t tr\u1ea1ng th\u00e1i h\u1ee3p l\u1ec7. \u0110\u00e2y l\u00e0 kh\u00e1i ni\u1ec7m v\u1ec1 <strong>invariants<\/strong> (b\u1ea5t bi\u1ebfn).<\/p>\n<p>Quay l\u1ea1i v\u00ed d\u1ee5 l\u1edbp <code>Account<\/code>. M\u1ed9t quy t\u1eafc b\u1ea5t bi\u1ebfn l\u00e0 s\u1ed1 d\u01b0 t\u00e0i kho\u1ea3n kh\u00f4ng bao gi\u1edd \u0111\u01b0\u1ee3c \u00e2m. N\u1ebfu kh\u00f4ng c\u00f3 <strong>Encapsulation<\/strong>, b\u1ea5t k\u1ef3 ai c\u0169ng c\u00f3 th\u1ec3 g\u00e1n <code>balance = -100<\/code>.<\/p>\n<p>V\u1edbi <strong>Encapsulation<\/strong>, ch\u00fang ta th\u00eam c\u00e1c logic ki\u1ec3m tra v\u00e0o ph\u01b0\u01a1ng th\u1ee9c <code>setter<\/code> \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o quy t\u1eafc n\u00e0y.<\/p>\n<pre><code>public class Account {\r\n    \/\/ ... thu\u1ed9c t\u00ednh\r\n\r\n    public void setBalance(double newBalance) {\r\n        if (newBalance &gt;= 0) {\r\n            this.balance = newBalance;\r\n        } else {\r\n            System.out.println(\"L\u1ed7i: S\u1ed1 d\u01b0 kh\u00f4ng th\u1ec3 l\u00e0 s\u1ed1 \u00e2m.\");\r\n        }\r\n    }\r\n}\r\n<\/code><\/pre>\n<p>L\u00fac n\u00e0y, m\u1ecdi thay \u0111\u1ed5i s\u1ed1 d\u01b0 \u0111\u1ec1u ph\u1ea3i qua <code>setBalance()<\/code>, v\u00e0 ph\u01b0\u01a1ng th\u1ee9c n\u00e0y s\u1ebd t\u1ef1 \u0111\u1ed9ng lo\u1ea1i b\u1ecf c\u00e1c gi\u00e1 tr\u1ecb kh\u00f4ng h\u1ee3p l\u1ec7. \u0110i\u1ec1u n\u00e0y gi\u00fap b\u1ea1n lo\u1ea1i b\u1ecf m\u1ed9t l\u1edbp l\u1ed7i quan tr\u1ecdng ngay t\u1eeb \u0111\u1ea7u.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"De-dang-bao-tri-va-mo-rong-code\"><\/span>D\u1ec5 d\u00e0ng b\u1ea3o tr\u00ec v\u00e0 m\u1edf r\u1ed9ng code<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Khi s\u1eed d\u1ee5ng <strong>Encapsulation<\/strong>, b\u1ea1n c\u00f3 th\u1ec3 thay \u0111\u1ed5i c\u00e1ch d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c l\u01b0u tr\u1eef ho\u1eb7c x\u1eed l\u00fd b\u00ean trong m\u1ed9t l\u1edbp m\u00e0 kh\u00f4ng l\u00e0m \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn c\u00e1c l\u1edbp kh\u00e1c \u0111ang s\u1eed d\u1ee5ng n\u00f3. \u0110i\u1ec1u n\u00e0y gi\u00fap vi\u1ec7c b\u1ea3o tr\u00ec v\u00e0 n\u00e2ng c\u1ea5p tr\u1edf n\u00ean d\u1ec5 d\u00e0ng h\u01a1n.<\/p>\n<p><strong>V\u00ed d\u1ee5:<\/strong> B\u1ea1n c\u00f3 m\u1ed9t l\u1edbp <code>Invoice<\/code> (H\u00f3a \u0111\u01a1n) v\u1edbi thu\u1ed9c t\u00ednh <code>totalAmount<\/code>. Ban \u0111\u1ea7u, <code>totalAmount<\/code> ch\u1ec9 \u0111\u01b0\u1ee3c t\u00ednh b\u1eb1ng t\u1ed5ng gi\u00e1 tr\u1ecb c\u1ee7a c\u00e1c m\u1eb7t h\u00e0ng. Nh\u01b0ng sau n\u00e0y, c\u00f4ng ty quy\u1ebft \u0111\u1ecbnh th\u00eam thu\u1ebf VAT v\u00e0o.<\/p>\n<ul>\n<li><strong>Kh\u00f4ng c\u00f3 Encapsulation:<\/strong> M\u1ecdi \u0111o\u1ea1n code truy c\u1eadp tr\u1ef1c ti\u1ebfp v\u00e0o <code>totalAmount<\/code> \u0111\u1ec1u ph\u1ea3i \u0111\u01b0\u1ee3c t\u00ecm v\u00e0 s\u1eeda. N\u1ebfu c\u00f3 h\u00e0ng tr\u0103m d\u00f2ng code truy c\u1eadp <code>totalAmount<\/code>, b\u1ea1n s\u1ebd m\u1ea5t r\u1ea5t nhi\u1ec1u th\u1eddi gian v\u00e0 c\u00f3 nguy c\u01a1 b\u1ecf s\u00f3t l\u1ed7i.<\/li>\n<li><strong>C\u00f3 Encapsulation:<\/strong> Thu\u1ed9c t\u00ednh <code>totalAmount<\/code> l\u00e0 <code>private<\/code>, v\u00e0 b\u1ea1n ch\u1ec9 truy c\u1eadp n\u00f3 qua m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c <code>calculateTotal()<\/code>. Khi c\u00f3 thay \u0111\u1ed5i, b\u1ea1n ch\u1ec9 c\u1ea7n s\u1eeda logic t\u00ednh to\u00e1n b\u00ean trong ph\u01b0\u01a1ng th\u1ee9c <code>calculateTotal()<\/code>. C\u00e1c ph\u1ea7n code kh\u00e1c \u0111ang g\u1ecdi ph\u01b0\u01a1ng th\u1ee9c n\u00e0y s\u1ebd kh\u00f4ng b\u1ecb \u1ea3nh h\u01b0\u1edfng. \u0110i\u1ec1u n\u00e0y l\u00e0m gi\u1ea3m \u0111\u00e1ng k\u1ec3 r\u1ee7i ro v\u00e0 chi ph\u00ed b\u1ea3o tr\u00ec.<\/li>\n<\/ul>\n<figure id=\"attachment_33366\" aria-describedby=\"caption-attachment-33366\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-33366\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-sao-Encapsulation-lai-quan-trong.jpg\" alt=\"V\u00ec sao Encapsulation l\u1ea1i quan tr\u1ecdng\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-sao-Encapsulation-lai-quan-trong.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-sao-Encapsulation-lai-quan-trong-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-sao-Encapsulation-lai-quan-trong-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-33366\" class=\"wp-caption-text\">V\u00ec sao Encapsulation l\u1ea1i quan tr\u1ecdng<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Cach-thuc-hoat-dong-cua-Encapsulation-Getter-va-Setter\"><\/span>C\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng c\u1ee7a Encapsulation: Getter v\u00e0 Setter<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Trong l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng, ch\u00fang ta th\u01b0\u1eddng s\u1eed d\u1ee5ng c\u00e1c ph\u01b0\u01a1ng th\u1ee9c <strong>Getter<\/strong> v\u00e0 <strong>Setter<\/strong> \u0111\u1ec3 truy c\u1eadp v\u00e0 thay \u0111\u1ed5i d\u1eef li\u1ec7u \u0111\u00e3 \u0111\u01b0\u1ee3c \u0111\u00f3ng g\u00f3i.<\/p>\n<ul>\n<li><strong>Getter (Ph\u01b0\u01a1ng th\u1ee9c Get):<\/strong> \u0110\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 l\u1ea5y gi\u00e1 tr\u1ecb c\u1ee7a m\u1ed9t thu\u1ed9c t\u00ednh <code>private<\/code>. N\u00f3 ch\u1ec9 cho ph\u00e9p \u0111\u1ecdc d\u1eef li\u1ec7u.<\/li>\n<li><strong>Setter (Ph\u01b0\u01a1ng th\u1ee9c Set):<\/strong> \u0110\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 g\u00e1n gi\u00e1 tr\u1ecb cho m\u1ed9t thu\u1ed9c t\u00ednh <code>private<\/code>. N\u00f3 cho ph\u00e9p ch\u00fang ta ki\u1ec3m tra d\u1eef li\u1ec7u \u0111\u1ea7u v\u00e0o tr\u01b0\u1edbc khi g\u00e1n.<\/li>\n<\/ul>\n<p><strong>V\u00ed d\u1ee5 code:<\/strong> H\u00e3y xem x\u00e9t m\u1ed9t l\u1edbp <code>Employee<\/code> (Nh\u00e2n vi\u00ean) trong <a href=\"https:\/\/interdata.vn\/blog\/ngon-ngu-lap-trinh-java\/\">ng\u00f4n ng\u1eef Java<\/a>.<\/p>\n<pre><code>public class Employee {\r\n    \/\/ Thu\u1ed9c t\u00ednh private\r\n    private String name;\r\n    private double salary;\r\n\r\n    \/\/ Constructor\r\n    public Employee(String name, double salary) {\r\n        this.name = name;\r\n        this.salary = salary;\r\n    }\r\n\r\n    \/\/ Getter cho name\r\n    public String getName() {\r\n        return name;\r\n    }\r\n\r\n    \/\/ Setter cho salary v\u1edbi logic ki\u1ec3m tra d\u1eef li\u1ec7u\r\n    public void setSalary(double salary) {\r\n        if (salary &gt; 0) {\r\n            this.salary = salary;\r\n        } else {\r\n            System.out.println(\"L\u01b0\u01a1ng kh\u00f4ng \u0111\u01b0\u1ee3c nh\u1ecf h\u01a1n ho\u1eb7c b\u1eb1ng 0.\");\r\n        }\r\n    }\r\n\r\n    \/\/ Getter cho salary\r\n    public double getSalary() {\r\n        return salary;\r\n    }\r\n}\r\n<\/code><\/pre>\n<p>Trong v\u00ed d\u1ee5 tr\u00ean, thu\u1ed9c t\u00ednh <code>salary<\/code> \u0111\u01b0\u1ee3c khai b\u00e1o l\u00e0 <code>private<\/code>, ngh\u0129a l\u00e0 kh\u00f4ng th\u1ec3 truy c\u1eadp tr\u1ef1c ti\u1ebfp t\u1eeb b\u00ean ngo\u00e0i. \u0110\u1ec3 thay \u0111\u1ed5i gi\u00e1 tr\u1ecb n\u00e0y, ch\u00fang ta ph\u1ea3i s\u1eed d\u1ee5ng ph\u01b0\u01a1ng th\u1ee9c <code>setSalary()<\/code>. Ph\u01b0\u01a1ng th\u1ee9c n\u00e0y c\u00f3 logic ki\u1ec3m tra \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o gi\u00e1 tr\u1ecb l\u01b0\u01a1ng lu\u00f4n h\u1ee3p l\u1ec7 (0).<\/p>\n<figure id=\"attachment_33367\" aria-describedby=\"caption-attachment-33367\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-33367\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Cach-thuc-hoat-dong-cua-Encapsulation.jpg\" alt=\"C\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng c\u1ee7a Encapsulation\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Cach-thuc-hoat-dong-cua-Encapsulation.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Cach-thuc-hoat-dong-cua-Encapsulation-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Cach-thuc-hoat-dong-cua-Encapsulation-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-33367\" class=\"wp-caption-text\">C\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng c\u1ee7a Encapsulation<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Phan-biet-Encapsulation-va-Abstraction\"><\/span>Ph\u00e2n bi\u1ec7t Encapsulation v\u00e0 Abstraction<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Encapsulation v\u00e0 Abstraction l\u00e0 hai kh\u00e1i ni\u1ec7m th\u01b0\u1eddng g\u00e2y nh\u1ea7m l\u1eabn nh\u1ea5t trong OOP. M\u1eb7c d\u00f9 c\u00f3 m\u1ed1i li\u00ean h\u1ec7 ch\u1eb7t ch\u1ebd, ch\u00fang ph\u1ee5c v\u1ee5 c\u00e1c m\u1ee5c \u0111\u00edch kh\u00e1c nhau.<\/p>\n<ul>\n<li><strong>Encapsulation (T\u00ednh \u0111\u00f3ng g\u00f3i):<\/strong>\n<ul>\n<li><strong>M\u1ee5c \u0111\u00edch:<\/strong> <strong>G\u00f3i g\u1ecdn<\/strong> d\u1eef li\u1ec7u v\u00e0 h\u00e0nh vi li\u00ean quan v\u00e0o m\u1ed9t l\u1edbp duy nh\u1ea5t.<\/li>\n<li><strong>\u0110\u00f3ng vai tr\u00f2:<\/strong> M\u1ed9t &#8220;h\u1ed9p ch\u1ee9a&#8221; b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u.<\/li>\n<li><strong>Gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1:<\/strong> <strong>L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u?<\/strong><\/li>\n<\/ul>\n<\/li>\n<li><strong>Abstraction (T\u00ednh tr\u1eebu t\u01b0\u1ee3ng):<\/strong>\n<ul>\n<li><strong>M\u1ee5c \u0111\u00edch:<\/strong> <strong>\u0110\u01a1n gi\u1ea3n h\u00f3a<\/strong> c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng ph\u1ee9c t\u1ea1p b\u1eb1ng c\u00e1ch ch\u1ec9 hi\u1ec3n th\u1ecb nh\u1eefng th\u00f4ng tin c\u1ea7n thi\u1ebft v\u00e0 che gi\u1ea5u \u0111i chi ti\u1ebft tri\u1ec3n khai.<\/li>\n<li><strong>\u0110\u00f3ng vai tr\u00f2:<\/strong> M\u1ed9t &#8220;giao di\u1ec7n \u0111\u01a1n gi\u1ea3n&#8221; cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng t\u01b0\u01a1ng t\u00e1c.<\/li>\n<li><strong>Gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1:<\/strong> <strong>L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 s\u1eed d\u1ee5ng \u0111\u1ed1i t\u01b0\u1ee3ng m\u1ed9t c\u00e1ch \u0111\u01a1n gi\u1ea3n?<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>H\u00e3y tr\u1edf l\u1ea1i v\u1edbi v\u00ed d\u1ee5 chi\u1ebfc xe m\u00e1y. <strong>Encapsulation<\/strong> l\u00e0 vi\u1ec7c to\u00e0n b\u1ed9 h\u1ec7 th\u1ed1ng \u0111\u1ed9ng c\u01a1 \u0111\u01b0\u1ee3c \u0111\u1eb7t trong m\u1ed9t l\u1edbp v\u1ecf. C\u00f2n <strong>Abstraction<\/strong> l\u00e0 vi\u1ec7c b\u1ea1n ch\u1ec9 th\u1ea5y n\u00fat kh\u1edfi \u0111\u1ed9ng, tay ga, tay phanh, m\u00e0 kh\u00f4ng c\u1ea7n bi\u1ebft c\u00e1ch th\u1ee9c \u0111\u1ed9ng c\u01a1 ho\u1ea1t \u0111\u1ed9ng, d\u00e2y \u0111i\u1ec7n \u0111\u1ea5u n\u1ed1i ra sao.<\/p>\n<figure id=\"attachment_33368\" aria-describedby=\"caption-attachment-33368\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-33368\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-va-Abstraction.jpg\" alt=\"Encapsulation v\u00e0 Abstraction\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-va-Abstraction.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-va-Abstraction-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Encapsulation-va-Abstraction-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-33368\" class=\"wp-caption-text\">Encapsulation v\u00e0 Abstraction<\/figcaption><\/figure>\n<div>\n<h2><span class=\"ez-toc-section\" id=\"Vi-du-thuc-te-ve-Encapsulation-trong-cac-ngon-ngu-lap-trinh-pho-bien\"><\/span>V\u00ed d\u1ee5 th\u1ef1c t\u1ebf v\u1ec1 Encapsulation trong c\u00e1c ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh ph\u1ed5 bi\u1ebfn<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Kh\u00e1i ni\u1ec7m \u0111\u00f3ng g\u00f3i (Encapsulation) l\u00e0 m\u1ed9t trong nh\u1eefng nguy\u00ean l\u00fd c\u01a1 b\u1ea3n c\u1ee7a l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng, gi\u00fap b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u v\u00e0 gi\u1ea3m s\u1ef1 ph\u1ee5 thu\u1ed9c gi\u1eefa c\u00e1c th\u00e0nh ph\u1ea7n trong h\u1ec7 th\u1ed1ng.<\/p>\n<p>Trong m\u00f4i tr\u01b0\u1eddng ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m hi\u1ec7n \u0111\u1ea1i, <a href=\"https:\/\/interdata.vn\/\"><strong>Interdata<\/strong><\/a> nh\u1eadn th\u1ea5y r\u1eb1ng \u0111\u00f3ng g\u00f3i kh\u00f4ng ch\u1ec9 gi\u00fap b\u1ea3o v\u1ec7 t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u m\u00e0 c\u00f2n h\u1ed7 tr\u1ee3 qu\u00e1 tr\u00ecnh b\u1ea3o tr\u00ec <a href=\"https:\/\/interdata.vn\/blog\/source-code-la-gi\/\">m\u00e3 ngu\u1ed3n<\/a>, t\u1ed1i \u01b0u h\u00f3a hi\u1ec7u su\u1ea5t v\u00e0 t\u0103ng t\u00ednh linh ho\u1ea1t trong vi\u1ec7c ph\u00e1t tri\u1ec3n \u1ee9ng d\u1ee5ng.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Encapsulation-trong-Java\"><\/span>Encapsulation trong Java<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Encapsulation trong Java l\u00e0 m\u1ed9t trong nh\u1eefng nguy\u00ean t\u1eafc c\u1ed1t l\u00f5i c\u1ee7a l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng, nh\u1eb1m b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u b\u00ean trong \u0111\u1ed1i t\u01b0\u1ee3ng kh\u1ecfi vi\u1ec7c truy c\u1eadp ho\u1eb7c s\u1eeda \u0111\u1ed5i tr\u00e1i ph\u00e9p t\u1eeb b\u00ean ngo\u00e0i. C\u01a1 ch\u1ebf n\u00e0y th\u1ef1c hi\u1ec7n b\u1eb1ng c\u00e1ch khai b\u00e1o c\u00e1c thu\u1ed9c t\u00ednh (bi\u1ebfn) c\u1ee7a l\u1edbp v\u1edbi ph\u1ea1m vi truy c\u1eadp l\u00e0 private, sau \u0111\u00f3 cung c\u1ea5p c\u00e1c ph\u01b0\u01a1ng th\u1ee9c public (getter v\u00e0 setter) \u0111\u1ec3 truy c\u1eadp v\u00e0 c\u1eadp nh\u1eadt c\u00e1c thu\u1ed9c t\u00ednh \u0111\u00f3 m\u1ed9t c\u00e1ch ki\u1ec3m so\u00e1t.<\/p>\n<pre><code>\r\npublic class Employee {\r\n\r\nprivate String name; \/\/ T\u00ean nh\u00e2n vi\u00ean, kh\u00f4ng th\u1ec3 truy c\u1eadp tr\u1ef1c ti\u1ebfp\r\n\r\nprivate int age; \/\/ Tu\u1ed5i nh\u00e2n vi\u00ean\r\n\r\nprivate double salary; \/\/ L\u01b0\u01a1ng nh\u00e2n vi\u00ean\r\n\r\npublic Employee(String name, int age, double salary) {\r\n\r\nthis.name = name;\r\n\r\nthis.age = age;\r\n\r\nthis.salary = salary;\r\n\r\n}\r\n\r\n\/\/ Getter cho name\r\n\r\npublic String getName() {\r\n\r\nreturn name;\r\n\r\n}\r\n\r\n\/\/ Getter cho age\r\n\r\npublic int getAge() {\r\n\r\nreturn age;\r\n\r\n}\r\n\r\n\/\/ Getter cho salary\r\n\r\npublic double getSalary() {\r\n\r\nreturn salary;\r\n\r\n}\r\n\r\n\/\/ Setter cho salary \u0111\u1ec3 ki\u1ec3m so\u00e1t vi\u1ec7c thay \u0111\u1ed5i l\u01b0\u01a1ng\r\n\r\npublic void setSalary(double salary) {\r\n\r\nif (salary &gt; 0) {\r\n\r\nthis.salary = salary;\r\n\r\n}\r\n\r\n}\r\n\r\n\/\/ Ph\u01b0\u01a1ng th\u1ee9c hi\u1ec3n th\u1ecb th\u00f4ng tin nh\u00e2n vi\u00ean\r\n\r\npublic void displayInfo() {\r\n\r\nSystem.out.println(\"T\u00ean: \" + name);\r\n\r\nSystem.out.println(\"Tu\u1ed5i: \" + age);\r\n\r\nSystem.out.println(\"L\u01b0\u01a1ng: \" + salary);\r\n\r\n}\r\n\r\n}\r\n<\/code><\/pre>\n<\/div>\n<div>\n<div>\n<div>\n<div>\n<div>\n<div>\n<div>\n<h3><span class=\"ez-toc-section\" id=\"Encapsulation-trong-Python\"><\/span><span style=\"font-size: 20.16px;\">Encapsulation trong Python<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p>Python kh\u00f4ng c\u00f3 c\u00e1c t\u1eeb kh\u00f3a <code>private<\/code> hay <code>public<\/code> th\u1ef1c s\u1ef1. Thay v\u00e0o \u0111\u00f3, n\u00f3 s\u1eed d\u1ee5ng m\u1ed9t quy \u01b0\u1edbc: thu\u1ed9c t\u00ednh b\u1eaft \u0111\u1ea7u b\u1eb1ng m\u1ed9t d\u1ea5u g\u1ea1ch d\u01b0\u1edbi (<code>_<\/code>) \u0111\u01b0\u1ee3c xem l\u00e0 <code>protected<\/code> v\u00e0 hai d\u1ea5u g\u1ea1ch d\u01b0\u1edbi (<code>__<\/code>) l\u00e0 <code>private<\/code>. Tuy nhi\u00ean, \u0111\u00e2y ch\u1ec9 l\u00e0 quy \u01b0\u1edbc v\u00e0 ch\u00fang ta v\u1eabn c\u00f3 th\u1ec3 truy c\u1eadp, nh\u01b0ng kh\u00f4ng n\u00ean l\u00e0m v\u1eady.<\/p>\n<pre><code>class Student:\r\n    def __init__(self, name, age):\r\n        self.__name = name # Thu\u1ed9c t\u00ednh \"private\"\r\n        self.__age = age\r\n\r\n    def get_name(self):\r\n        return self.__name\r\n\r\n    def set_age(self, age):\r\n        if 0 &lt; age &lt; 120:\r\n            self.__age = age\r\n        else:\r\n            print(\"Tu\u1ed5i kh\u00f4ng h\u1ee3p l\u1ec7\")\r\n<\/code><\/pre>\n<figure id=\"attachment_33369\" aria-describedby=\"caption-attachment-33369\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-33369\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-du-thuc-te-ve-Encapsulation.jpg\" alt=\"V\u00ed d\u1ee5 th\u1ef1c t\u1ebf v\u1ec1 Encapsulation\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-du-thuc-te-ve-Encapsulation.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-du-thuc-te-ve-Encapsulation-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Vi-du-thuc-te-ve-Encapsulation-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-33369\" class=\"wp-caption-text\">V\u00ed d\u1ee5 th\u1ef1c t\u1ebf v\u1ec1 Encapsulation<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Loi-khuyen-khi-su-dung-Encapsulation\"><\/span>L\u1eddi khuy\u00ean khi s\u1eed d\u1ee5ng Encapsulation<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong>\u0110\u00f3ng g\u00f3i d\u1eef li\u1ec7u<\/strong> kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t nguy\u00ean t\u1eafc c\u1ee9ng nh\u1eafc. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 l\u1eddi khuy\u00ean \u0111\u1ec3 \u00e1p d\u1ee5ng n\u00f3 m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3:<\/p>\n<ul>\n<li><strong>Kh\u00f4ng ph\u1ea3i t\u1ea5t c\u1ea3 thu\u1ed9c t\u00ednh \u0111\u1ec1u c\u1ea7n <code>private<\/code>:<\/strong> V\u1edbi m\u1ed9t s\u1ed1 tr\u01b0\u1eddng h\u1ee3p \u0111\u01a1n gi\u1ea3n, b\u1ea1n c\u00f3 th\u1ec3 \u0111\u1ec3 thu\u1ed9c t\u00ednh l\u00e0 <code>public<\/code> \u0111\u1ec3 truy c\u1eadp nhanh. Tuy nhi\u00ean, n\u1ebfu d\u1eef li\u1ec7u c\u00f3 th\u1ec3 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn logic ch\u01b0\u01a1ng tr\u00ecnh, h\u00e3y lu\u00f4n s\u1eed d\u1ee5ng <code>private<\/code> v\u00e0 <code>getter\/setter<\/code>.<\/li>\n<li><strong>S\u1eed d\u1ee5ng <code>setter<\/code> \u0111\u1ec3 ki\u1ec3m tra d\u1eef li\u1ec7u:<\/strong> \u0110\u1eebng ch\u1ec9 t\u1ea1o <code>setter<\/code> m\u1ed9t c\u00e1ch m\u00e1y m\u00f3c. H\u00e3y th\u00eam c\u00e1c logic ki\u1ec3m tra d\u1eef li\u1ec7u \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n.<\/li>\n<li><strong>K\u1ebft h\u1ee3p v\u1edbi c\u00e1c nguy\u00ean t\u1eafc OOP kh\u00e1c:<\/strong> Encapsulation ph\u00e1t huy s\u1ee9c m\u1ea1nh l\u1edbn nh\u1ea5t khi k\u1ebft h\u1ee3p v\u1edbi Abstraction, Inheritance v\u00e0 Polymorphism.<\/li>\n<\/ul>\n<figure id=\"attachment_33370\" aria-describedby=\"caption-attachment-33370\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-33370\" src=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Loi-khuyen-khi-su-dung-Encapsulation.jpg\" alt=\"L\u1eddi khuy\u00ean khi s\u1eed d\u1ee5ng Encapsulation\" width=\"800\" height=\"500\" title=\"\" srcset=\"https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Loi-khuyen-khi-su-dung-Encapsulation.jpg 800w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Loi-khuyen-khi-su-dung-Encapsulation-300x188.jpg 300w, https:\/\/interdata.vn\/blog\/wp-content\/uploads\/2025\/09\/Loi-khuyen-khi-su-dung-Encapsulation-768x480.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-33370\" class=\"wp-caption-text\">L\u1eddi khuy\u00ean khi s\u1eed d\u1ee5ng Encapsulation<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Cac-cau-hoi-thuong-gap-ve-Encapsulation\"><\/span>C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p v\u1ec1 Encapsulation<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Encapsulation-la-gi-2\"><\/span>Encapsulation l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Encapsulation (t\u00ednh \u0111\u00f3ng g\u00f3i) l\u00e0 qu\u00e1 tr\u00ecnh gom nh\u00f3m d\u1eef li\u1ec7u v\u00e0 c\u00e1c ph\u01b0\u01a1ng th\u1ee9c thao t\u00e1c l\u00ean d\u1eef li\u1ec7u \u0111\u00f3 v\u00e0o trong m\u1ed9t l\u1edbp (class), \u0111\u1ed3ng th\u1eddi che gi\u1ea5u c\u00e1c chi ti\u1ebft b\u00ean trong \u0111\u1ec3 ng\u01b0\u1eddi d\u00f9ng ch\u1ec9 c\u00f3 th\u1ec3 truy c\u1eadp d\u1eef li\u1ec7u th\u00f4ng qua c\u00e1c ph\u01b0\u01a1ng th\u1ee9c \u0111\u01b0\u1ee3c c\u00f4ng b\u1ed1 (public). \u0110\u00e2y l\u00e0 c\u00e1ch b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u kh\u00f4ng b\u1ecb truy c\u1eadp hay thay \u0111\u1ed5i sai m\u1ee5c \u0111\u00edch t\u1eeb b\u00ean ngo\u00e0i l\u1edbp.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Tai-sao-can-su-dung-tinh-dong-goi\"><\/span>T\u1ea1i sao c\u1ea7n s\u1eed d\u1ee5ng t\u00ednh \u0111\u00f3ng g\u00f3i?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Vi\u1ec7c s\u1eed d\u1ee5ng encapsulation gi\u00fap b\u1ea3o v\u1ec7 d\u1eef li\u1ec7u kh\u1ecfi s\u1ef1 truy c\u1eadp ho\u1eb7c thay \u0111\u1ed5i tr\u00e1i ph\u00e9p, \u0111\u1ea3m b\u1ea3o s\u1ef1 to\u00e0n v\u1eb9n c\u1ee7a d\u1eef li\u1ec7u. N\u00f3 c\u00f2n gi\u00fap gi\u1ea3m s\u1ef1 ph\u1ee5 thu\u1ed9c gi\u1eefa c\u00e1c th\u00e0nh ph\u1ea7n trong ch\u01b0\u01a1ng tr\u00ecnh, thu\u1eadn ti\u1ec7n cho vi\u1ec7c qu\u1ea3n l\u00fd v\u00e0 b\u1ea3o tr\u00ec m\u00e3 ngu\u1ed3n, \u0111\u1ed3ng th\u1eddi khi\u1ebfn giao di\u1ec7n l\u1eadp tr\u00ecnh tr\u1edf n\u00ean r\u00f5 r\u00e0ng h\u01a1n b\u1eb1ng c\u00e1ch \u1ea9n \u0111i c\u00e1c chi ti\u1ebft c\u00e0i \u0111\u1eb7t n\u1ed9i b\u1ed9.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Lam-cach-nao-de-thuc-hien-tinh-dong-goi-trong-lap-trinh\"><\/span>L\u00e0m c\u00e1ch n\u00e0o \u0111\u1ec3 th\u1ef1c hi\u1ec7n t\u00ednh \u0111\u00f3ng g\u00f3i trong l\u1eadp tr\u00ecnh?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>T\u00ednh \u0111\u00f3ng g\u00f3i \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n b\u1eb1ng c\u00e1ch khai b\u00e1o c\u00e1c thu\u1ed9c t\u00ednh (d\u1eef li\u1ec7u) c\u1ee7a l\u1edbp \u1edf ph\u1ea1m vi truy c\u1eadp private ho\u1eb7c protected \u0111\u1ec3 kh\u00f4ng th\u1ec3 truy c\u1eadp tr\u1ef1c ti\u1ebfp t\u1eeb b\u00ean ngo\u00e0i l\u1edbp, v\u00e0 cung c\u1ea5p c\u00e1c ph\u01b0\u01a1ng th\u1ee9c public (getter, setter) \u0111\u1ec3 truy xu\u1ea5t ho\u1eb7c c\u1eadp nh\u1eadt gi\u00e1 tr\u1ecb c\u1ee7a c\u00e1c thu\u1ed9c t\u00ednh \u0111\u00f3 m\u1ed9t c\u00e1ch ki\u1ec3m so\u00e1t \u0111\u01b0\u1ee3c. Nh\u1edd v\u1eady, d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c &#8220;\u0111\u00f3ng g\u00f3i&#8221; v\u00e0 b\u1ea3o v\u1ec7 kh\u1ecfi truy c\u1eadp kh\u00f4ng \u0111\u00fang c\u00e1ch.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Encapsulation-co-phai-la-che-giau-du-lieu-khong\"><\/span>Encapsulation c\u00f3 ph\u1ea3i l\u00e0 che gi\u1ea5u d\u1eef li\u1ec7u kh\u00f4ng?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>\u0110\u00fang v\u1eady. Che gi\u1ea5u d\u1eef li\u1ec7u l\u00e0 m\u1ed9t ph\u1ea7n c\u1ee7a Encapsulation. M\u1ee5c ti\u00eau c\u1ee7a <strong>t\u00ednh \u0111\u00f3ng g\u00f3i<\/strong> l\u00e0 g\u00f3i d\u1eef li\u1ec7u v\u00e0 ph\u01b0\u01a1ng th\u1ee9c v\u00e0o m\u1ed9t \u0111\u01a1n v\u1ecb, v\u00e0 vi\u1ec7c che gi\u1ea5u d\u1eef li\u1ec7u l\u00e0 m\u1ed9t trong nh\u1eefng l\u1ee3i \u00edch quan tr\u1ecdng nh\u1ea5t c\u1ee7a n\u00f3.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Ket-luan\"><\/span>K\u1ebft lu\u1eadn<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong>Encapsulation<\/strong> l\u00e0 m\u1ed9t tr\u1ee5 c\u1ed9t kh\u00f4ng th\u1ec3 thi\u1ebfu c\u1ee7a l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng. N\u1eafm v\u1eefng kh\u00e1i ni\u1ec7m n\u00e0y kh\u00f4ng ch\u1ec9 gi\u00fap b\u1ea1n hi\u1ec3u s\u00e2u h\u01a1n v\u1ec1 OOP, m\u00e0 c\u00f2n trang b\u1ecb cho b\u1ea1n k\u1ef9 n\u0103ng \u0111\u1ec3 vi\u1ebft code s\u1ea1ch h\u01a1n, an to\u00e0n h\u01a1n v\u00e0 d\u1ec5 d\u00e0ng qu\u1ea3n l\u00fd h\u01a1n. Vi\u1ec7c \u00e1p d\u1ee5ng \u0111\u00fang <strong>t\u00ednh \u0111\u00f3ng g\u00f3i<\/strong> s\u1ebd l\u00e0 b\u01b0\u1edbc \u0111\u1ec7m v\u1eefng ch\u1eafc tr\u00ean con \u0111\u01b0\u1eddng tr\u1edf th\u00e0nh m\u1ed9t l\u1eadp tr\u00ecnh vi\u00ean chuy\u00ean nghi\u1ec7p.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>M\u1ed9t trong b\u1ed1n tr\u1ee5 c\u1ed9t c\u1ee7a l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng (OOP), Encapsulation hay t\u00ednh \u0111\u00f3ng g\u00f3i \u0111\u00f3ng vai tr\u00f2 then ch\u1ed1t trong vi\u1ec7c x\u00e2y d\u1ef1ng ph\u1ea7n m\u1ec1m an to\u00e0n, d\u1ec5 b\u1ea3o tr\u00ec. N\u1ebfu b\u1ea1n \u0111ang b\u0103n kho\u0103n v\u1ec1 kh\u00e1i ni\u1ec7m n\u00e0y, b\u00e0i vi\u1ebft s\u1ebd gi\u00fap b\u1ea1n n\u1eafm v\u1eefng t\u1eeb A-Z. Ch\u00fang ta s\u1ebd c\u00f9ng<\/p>\n","protected":false},"author":27,"featured_media":33371,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[151],"tags":[],"class_list":["post-33362","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mang"],"_links":{"self":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/33362","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/users\/27"}],"replies":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/comments?post=33362"}],"version-history":[{"count":18,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/33362\/revisions"}],"predecessor-version":[{"id":33407,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/posts\/33362\/revisions\/33407"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media\/33371"}],"wp:attachment":[{"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/media?parent=33362"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/categories?post=33362"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/interdata.vn\/blog\/wp-json\/wp\/v2\/tags?post=33362"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}