{"id":20115,"date":"2023-05-25T10:47:35","date_gmt":"2023-05-25T03:47:35","guid":{"rendered":"https:\/\/jobsgo.vn\/blog\/?p=20115"},"modified":"2025-03-25T11:38:04","modified_gmt":"2025-03-25T04:38:04","slug":"cau-hoi-phong-van-java","status":"publish","type":"post","link":"https:\/\/jobsgo.vn\/blog\/cau-hoi-phong-van-java\/","title":{"rendered":"Top 35+ c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java c\u00f9ng h\u01b0\u1edbng d\u1eabn tr\u1ea3 l\u1eddi"},"content":{"rendered":"\n<div class=\"kk-star-ratings\n     kksr-valign-top     kksr-align-left    \"\n    data-payload=\"{&quot;align&quot;:&quot;left&quot;,&quot;id&quot;:&quot;20115&quot;,&quot;slug&quot;:&quot;default&quot;,&quot;valign&quot;:&quot;top&quot;,&quot;reference&quot;:&quot;auto&quot;,&quot;count&quot;:&quot;1&quot;,&quot;readonly&quot;:&quot;&quot;,&quot;score&quot;:&quot;5&quot;,&quot;best&quot;:&quot;5&quot;,&quot;gap&quot;:&quot;5&quot;,&quot;greet&quot;:&quot;\\u0110\\u00e1nh gi\\u00e1 post&quot;,&quot;legend&quot;:&quot;5\\\/5 - (1 vote)&quot;,&quot;size&quot;:&quot;22&quot;,&quot;width&quot;:&quot;132.5&quot;,&quot;_legend&quot;:&quot;{score}\\\/{best} - ({count} {votes})&quot;}\">\n    \n<div class=\"kksr-stars\">\n    \n<div class=\"kksr-stars-inactive\">\n            <div class=\"kksr-star\" data-star=\"1\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"2\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"3\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"4\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"5\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n    <\/div>\n    \n<div class=\"kksr-stars-active\" style=\"width: 132.5px;\">\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 22px; height: 22px;\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n    \n<div class=\"kksr-legend\">\n            5\/5 - (1 vote)    <\/div>\n<\/div>\n<p><em>B\u1ea1n \u0111ang chu\u1ea9n b\u1ecb tham gia bu\u1ed5i ph\u1ecfng v\u1ea5n Java th\u00ec vi\u1ec7c chu\u1ea9n b\u1ecb nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java l\u00e0 v\u00f4 c\u00f9ng c\u1ea7n thi\u1ebft. V\u00ec th\u1ebf, JobsGO \u0111\u00e3 t\u1ed5ng h\u1ee3p b\u1ed9<\/em> <a href=\"https:\/\/jobsgo.vn\/blog\/cau-hoi-phong-van-java\/#c\u00e2u_h\u1ecfi_ph\u1ecfng_v\u1ea5n_java\" target=\"_blank\" rel=\"noopener\"><strong><em>c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java<\/em><\/strong><\/a><em> chu\u1ea9n nh\u1ea5t n\u0103m 2023 \u0111\u1ec3 c\u00e1c b\u1ea1n c\u00f3 \u0111\u01b0\u1ee3c bu\u1ed5i Interview th\u00e0nh c\u00f4ng nh\u1ea5t.<\/em><\/p>\n<div id=\"toc_container\" class=\"toc_light_blue no_bullets\"><p class=\"toc_title\">M\u1ee5c l\u1ee5c<\/p><ul class=\"toc_list\"><li><a href=\"#1_Nhung_cau_hoi_phong_van_Fresher_Java\">1. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Fresher Java<\/a><ul><li><a href=\"#Cau_1_Java_duoc_phat_trien_boi_don_vi_nao\">C\u00e2u 1: Java \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi \u0111\u01a1n v\u1ecb n\u00e0o?<\/a><\/li><li><a href=\"#Cau_2_Java_dang_ho_tro_tren_nhung_nen_tang_nao\">C\u00e2u 2: Java \u0111ang h\u1ed7 tr\u1ee3 tr\u00ean nh\u1eefng n\u1ec1n t\u1ea3ng n\u00e0o?<\/a><\/li><li><a href=\"#Cau_3_Java_va_Java_Core_la_gi\">C\u00e2u 3: Java v\u00e0 Java Core l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_4_Classloader_trong_Java_la_gi\">C\u00e2u 4: Classloader trong Java l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_5_File_co_ten_trong_8220java8221_co_hop_le_khong\">C\u00e2u 5: File c\u00f3 t\u00ean tr\u1ed1ng &#8220;.java&#8221; c\u00f3 h\u1ee3p l\u1ec7 kh\u00f4ng?<\/a><\/li><li><a href=\"#Cau_6_Platform_la_gi\">C\u00e2u 6: Platform l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_7_Nhung_dac_diem_ma_Java_fresher_nen_biet_ve_Java_la_gi\">C\u00e2u 7: Nh\u1eefng \u0111\u1eb7c \u0111i\u1ec3m m\u00e0 Java fresher n\u00ean bi\u1ebft v\u1ec1 Java l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_8_Checked_Exception_la_gi\">C\u00e2u 8: Checked Exception l\u00e0 g\u00ec?<\/a><\/li><\/ul><\/li><li><a href=\"#2_Nhung_cau_hoi_phong_van_Java_Collection\">2. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java Collection<\/a><ul><li><a href=\"#Cau_1_Cho_biet_cac_interface_co_ban_cua_Java_Collections_framework\">C\u00e2u 1: Cho bi\u1ebft c\u00e1c interface c\u01a1 b\u1ea3n c\u1ee7a Java Collections framework?<\/a><\/li><li><a href=\"#Cau_2_Iterator_la_gi_trong_Java_Collection\">C\u00e2u 2: Iterator l\u00e0 g\u00ec trong Java Collection?<\/a><\/li><li><a href=\"#Cau_3_Giai_thich_su_khac_nhau_giua_ListIterator_va_Iterator\">C\u00e2u 3: Gi\u1ea3i th\u00edch s\u1ef1 kh\u00e1c nhau gi\u1eefa ListIterator v\u00e0 Iterator?<\/a><\/li><li><a href=\"#Cau_4_Su_khac_nhau_giua_ArrayList_va_LinkedList_la_gi\">C\u00e2u 4: S\u1ef1 kh\u00e1c nhau gi\u1eefa ArrayList v\u00e0 LinkedList l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_5_Phuong_thuc_hashCode_la_gi\">C\u00e2u 5: Ph\u01b0\u01a1ng th\u1ee9c hashCode() l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_6_Loi_the_cua_Properties_file_la_gi\">C\u00e2u 6: L\u1ee3i th\u1ebf c\u1ee7a Properties file l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_7_Tai_sao_chung_ta_phai_ghi_de_phuong_thuc_equals\">C\u00e2u 7: T\u1ea1i sao ch\u00fang ta ph\u1ea3i ghi \u0111\u00e8 ph\u01b0\u01a1ng th\u1ee9c equals()?<\/a><\/li><li><a href=\"#Cau_8_Hash-collision_trong_Hashtable_la_gi_Va_no_duoc_xu_ly_nhu_the_nao\">C\u00e2u 8: Hash-collision trong Hashtable l\u00e0 g\u00ec? V\u00e0 n\u00f3 \u0111\u01b0\u1ee3c x\u1eed l\u00fd nh\u01b0 th\u1ebf n\u00e0o?<\/a><\/li><\/ul><\/li><li><a href=\"#3_Nhung_cau_hoi_phong_van_JavaScript\">3. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n JavaScript<\/a><ul><li><a href=\"#Cau_1_Prototypal_inheritance_va_classical_inheritance_trong_JavaScript_la_gi\">C\u00e2u 1: Prototypal inheritance v\u00e0 classical inheritance trong JavaScript l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_2_Lap_trinh_khong_dong_bo_trong_JavaScript_la_gi\">C\u00e2u 2: L\u1eadp tr\u00ecnh kh\u00f4ng \u0111\u1ed3ng b\u1ed9 trong JavaScript l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_3_Functional_programming_la_gi\">C\u00e2u 3: Functional programming l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_4_Co_bao_nhieu_kieu_du_lieu_trong_JavaScript\">C\u00e2u 4: C\u00f3 bao nhi\u00eau ki\u1ec3u d\u1eef li\u1ec7u trong JavaScript?<\/a><\/li><li><a href=\"#Cau_5_Phan_biet_var_let_va_const\">C\u00e2u 5: Ph\u00e2n bi\u1ec7t var, let v\u00e0 const?<\/a><\/li><li><a href=\"#Cau_6_Strict_mode_trong_javascript_la_gi\">C\u00e2u 6: Strict mode trong javascript l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_7_Anonymous_function_la_gi\">C\u00e2u 7: Anonymous function l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_8_Ham_Arraysplice_va_ham_Arrayslice_khac_nhau_nhu_the_nao\">C\u00e2u 8: H\u00e0m Array.splice() v\u00e0 h\u00e0m Array.slice() kh\u00e1c nhau nh\u01b0 th\u1ebf n\u00e0o?<\/a><\/li><\/ul><\/li><li><a href=\"#4_Nhung_cau_hoi_phong_van_Java_Spring\">4. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java Spring<\/a><ul><li><a href=\"#Cau_1_The_nao_Spring_trong_Java\">C\u00e2u 1: Th\u1ebf n\u00e0o Spring trong Java?<\/a><\/li><li><a href=\"#Cau_2_Hien_nay_Java_Spring_co_bao_nhieu_phien_ban\">C\u00e2u 2: Hi\u1ec7n nay Java Spring c\u00f3 bao nhi\u00eau phi\u00ean b\u1ea3n?<\/a><\/li><li><a href=\"#Cau_3_Spring_Boot_la_gi\">C\u00e2u 3: Spring Boot l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_4_Loi_the_cua_Java_Spring_la_gi\">C\u00e2u 4: L\u1ee3i th\u1ebf c\u1ee7a Java Spring l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_5_Spring_co_bao_nhieu_module_khac_nhau\">C\u00e2u 5: Spring c\u00f3 bao nhi\u00eau module kh\u00e1c nhau?<\/a><\/li><li><a href=\"#Cau_6_IOC_la_gi\">C\u00e2u 6: IOC l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_7_Co_bao_nhieu_cach_de_thuc_hien_Dependency_Injection\">C\u00e2u 7: C\u00f3 bao nhi\u00eau c\u00e1ch \u0111\u1ec3 th\u1ef1c hi\u1ec7n Dependency Injection?<\/a><\/li><li><a href=\"#Cau_8_XML_file_la_gi\">C\u00e2u 8: XML file l\u00e0 g\u00ec?<\/a><\/li><\/ul><\/li><li><a href=\"#5_Nhung_cau_hoi_phong_van_huong_doi_tuong_OOP\">5. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng OOP<\/a><ul><li><a href=\"#Cau_1_Lap_trinh_huong_doi_tuong_OOP_gom_nhung_gi\">C\u00e2u 1: L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng OOP g\u1ed3m nh\u1eefng g\u00ec?<\/a><\/li><li><a href=\"#Cau_2_Da_hinh_la_gi_Co_may_loai_da_hinh\">C\u00e2u 2: \u0110a h\u00ecnh l\u00e0 g\u00ec? C\u00f3 m\u1ea5y lo\u1ea1i \u0111a h\u00ecnh?<\/a><\/li><li><a href=\"#Cau_3_Java_8_co_nhung_tinh_nang_quan_trong_nao\">C\u00e2u 3: Java 8 c\u00f3 nh\u1eefng t\u00ednh n\u0103ng quan tr\u1ecdng n\u00e0o?<\/a><\/li><li><a href=\"#Cau_4_Cac_tinh_chat_cua_huong_doi_tuong_la_gi\">C\u00e2u 4: C\u00e1c t\u00ednh ch\u1ea5t c\u1ee7a h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 g\u00ec?<\/a><\/li><li><a href=\"#Cau_5_Co_may_loai_access_modifier_Phan_biet_su_khac_nhau_giua_chung\">C\u00e2u 5: C\u00f3 m\u1ea5y lo\u1ea1i access modifier? Ph\u00e2n bi\u1ec7t s\u1ef1 kh\u00e1c nhau gi\u1eefa ch\u00fang?<\/a><\/li><li><a href=\"#Cau_6_Interface_co_the_la_final_khong\">C\u00e2u 6: Interface c\u00f3 th\u1ec3 l\u00e0 final kh\u00f4ng?<\/a><\/li><li><a href=\"#Cau_7_The_nao_la_tinh_dong_goi\">C\u00e2u 7: Th\u1ebf n\u00e0o l\u00e0 t\u00ednh \u0111\u00f3ng g\u00f3i?<\/a><\/li><li><a href=\"#Cau_8_Co_bat_buoc_phai_khai_bao_constructor_trong_lop\">C\u00e2u 8: C\u00f3 b\u1eaft bu\u1ed9c ph\u1ea3i khai b\u00e1o constructor trong l\u1edbp?<\/a><\/li><\/ul><\/li><\/ul><\/div>\n<h2><span id=\"1_Nhung_cau_hoi_phong_van_Fresher_Java\"><strong>1. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Fresher Java<\/strong><\/span><\/h2>\n<figure id=\"attachment_55171\" aria-describedby=\"caption-attachment-55171\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" class=\"size-full wp-image-55171\" src=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java.jpg\" alt=\"nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n java\" width=\"800\" height=\"444\" srcset=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java.jpg 800w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-300x167.jpg 300w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-150x83.jpg 150w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-768x426.jpg 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-55171\" class=\"wp-caption-text\"><center><strong><em>Nh\u1eefng c\u00e2u h\u1ecfi <a href=\"https:\/\/jobsgo.vn\/blog\/phong-van-xin-viec\/#ph%E1%BB%8Fng_v%E1%BA%A5n_xin_vi%E1%BB%87c\" target=\"_blank\" rel=\"noopener\">ph\u1ecfng v\u1ea5n xin vi\u1ec7c<\/a> Fresher Java<\/em><\/strong><\/center><\/figcaption><\/figure>\n<h3><span id=\"Cau_1_Java_duoc_phat_trien_boi_don_vi_nao\"><strong>C\u00e2u 1: Java \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi \u0111\u01a1n v\u1ecb n\u00e0o?<\/strong><\/span><\/h3>\n<blockquote id=\"c\u00e1c_c\u00e2u_h\u1ecfi_ph\u1ecfng_v\u1ea5n_l\u1eadp_tr\u00ecnh_vi\u00ean_java\" cite=\"https:\/\/jobsgo.vn\/blog\/cau-hoi-phong-van-java\/#cau_hoi_java_core\"><p>Java \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi \u0111\u01a1n v\u1ecb n\u00e0o th\u01b0\u1eddng l\u00e0 c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java ph\u1ed5 bi\u1ebfn d\u00e0nh cho th\u1ef1c t\u1eadp, th\u00f4ng qua \u0111\u00f3 nh\u00e0 tuy\u1ec3n d\u1ee5ng c\u00f3 th\u1ec3 \u0111\u00e1nh gi\u00e1 s\u01a1 b\u1ed9 v\u1ec1 m\u1ee9c \u0111\u1ed9 hi\u1ec3u bi\u1ebft c\u1ee7a b\u1ea1n v\u1ec1 lo\u1ea1i ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh n\u00e0y.<\/p><\/blockquote>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Java l\u00e0 ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh ph\u1ed5 bi\u1ebfn th\u1ebf gi\u1edbi \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n b\u1edfi Sun Microsystems. Java \u0111\u01b0\u1ee3c ra m\u1eaft v\u00e0 c\u00f4ng b\u1ed1 n\u0103m 1995.<\/p>\n<h3><span id=\"Cau_2_Java_dang_ho_tro_tren_nhung_nen_tang_nao\"><strong>C\u00e2u 2: Java \u0111ang h\u1ed7 tr\u1ee3 tr\u00ean nh\u1eefng n\u1ec1n t\u1ea3ng n\u00e0o?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Java c\u00f3 th\u1ec3 ch\u1ea1y tr\u00ean r\u1ea5t nhi\u1ec1u n\u1ec1n t\u1ea3ng kh\u00e1c nhau nh\u01b0 Mac OS, Linux, Windows, Sun Solaris, HP \u2013 Unix,\u2026 <span class=\"ng-star-inserted\">Ngo\u00e0i ra, n\u1ebfu b\u1ea1n mu\u1ed1n m\u1edf r\u1ed9ng ki\u1ebfn th\u1ee9c sang\u00a0<\/span><a href=\"https:\/\/jobsgo.vn\/blog\/lap-trinh-android-2\/\"><strong class=\"ng-star-inserted\"><span class=\"ng-star-inserted\">l\u1eadp tr\u00ecnh Android 2<\/span><\/strong><\/a><span class=\"ng-star-inserted\">\u00a0ho\u1eb7c c\u00e1c n\u1ec1n t\u1ea3ng di \u0111\u1ed9ng kh\u00e1c, b\u1ea1n c\u00f3 th\u1ec3 t\u00ecm hi\u1ec3u th\u00eam v\u1ec1\u00a0<\/span><a href=\"https:\/\/jobsgo.vn\/blog\/flutter-la-gi\/\"><strong class=\"ng-star-inserted\"><span class=\"ng-star-inserted\">Flutter l\u00e0 g\u00ec<\/span><\/strong><\/a><span class=\"ng-star-inserted\">, m\u1ed9t framework ph\u00e1t tri\u1ec3n \u1ee9ng d\u1ee5ng \u0111a n\u1ec1n t\u1ea3ng r\u1ea5t ph\u1ed5 bi\u1ebfn hi\u1ec7n nay.<\/span><\/p>\n<h3><span id=\"Cau_3_Java_va_Java_Core_la_gi\"><strong>C\u00e2u 3: Java v\u00e0 Java Core l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Java l\u00e0 ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh c\u1ea5p cao c\u00f3 m\u1ee5c \u0111\u00edch chung d\u1ef1a tr\u00ean c\u00e1c kh\u00e1i ni\u1ec7m c\u1ee7a ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng c\u1ea5p cao, c\u00fa ph\u00e1p n\u00f3 s\u1eed d\u1ee5ng h\u1ea7u h\u1ebft l\u00e0 c\u1ee7a C v\u00e0 C++.<\/p>\n<p>C\u00f2n Java Core l\u00e0 1 ph\u1ea7n c\u1ee7a Java \u0111\u1ec3 ph\u00e1t tri\u1ec3n m\u00e3 kh\u1ea3 chuy\u1ec3n cho nh\u1eefng \u1ee9ng d\u1ee5ng desktop v\u00e0 m\u00f4i tr\u01b0\u1eddng m\u00e1y ch\u1ee7.<\/p>\n<h3><span id=\"Cau_4_Classloader_trong_Java_la_gi\"><strong>C\u00e2u 4: Classloader trong Java l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Classloader l\u00e0 m\u1ed9t h\u1ec7 th\u1ed1ng con c\u1ee7a Java Virtual Machine. N\u00f3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 t\u1ea3i c\u00e1c l\u1edbp v\u00e0 c\u00e1c interface. Hi\u1ec7n nay, c\u00f3 r\u1ea5t nhi\u1ec1u lo\u1ea1i Classloader nh\u01b0: Bootstrap classloader, System classloader, Extension classloader&#8230;<\/p>\n<h3><span id=\"Cau_5_File_co_ten_trong_8220java8221_co_hop_le_khong\"><strong>C\u00e2u 5: File c\u00f3 t\u00ean tr\u1ed1ng &#8220;.java&#8221; c\u00f3 h\u1ee3p l\u1ec7 kh\u00f4ng?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> File n\u00e0y v\u1eabn h\u1ee3p l\u1ec7. Ng\u01b0\u1eddi d\u00f9ng ho\u00e0n to\u00e0n c\u00f3 th\u1ec3 l\u01b0u file v\u1edbi t\u00ean &#8220;.java&#8221;. Tuy nhi\u00ean, sau \u0111\u00f3, ng\u01b0\u1eddi d\u00f9ng c\u1ea7n bi\u00ean d\u1ecbch b\u1eb1ng l\u1ec7nh javac .java v\u00e0 ch\u1ea1y b\u1eb1ng l\u1ec7nh java ten_lop.<\/p>\n<h3><span id=\"Cau_6_Platform_la_gi\"><strong>C\u00e2u 6: Platform l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Platform \u0111\u01b0\u1ee3c hi\u1ec3u l\u00e0 m\u1ecdi m\u00f4i tr\u01b0\u1eddng ph\u1ea7n m\u1ec1m, ph\u1ea7n c\u1ee9ng c\u00f3 ch\u1ee9a m\u1ed9t ch\u01b0\u01a1ng tr\u00ecnh ch\u1ea1y. Ch\u1eb3ng h\u1ea1n, v\u1edbi m\u00f4i tr\u01b0\u1eddng runtime ri\u00eang cho m\u00ecnh (JRE) v\u00e0 API, Java \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 Platform.<\/p>\n<p><strong>Xem th\u00eam: [T\u1ed5ng h\u1ee3p] <a href=\"https:\/\/jobsgo.vn\/blog\/cau-hoi-phong-van-lap-trinh-vien\/\" target=\"_blank\" rel=\"noopener\">C\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n l\u1eadp tr\u00ecnh vi\u00ean<\/a> b\u1ea1n nh\u1ea5t \u0111\u1ecbnh ph\u1ea3i bi\u1ebft<\/strong><\/p>\n<h3><span id=\"Cau_7_Nhung_dac_diem_ma_Java_fresher_nen_biet_ve_Java_la_gi\"><strong>C\u00e2u 7: Nh\u1eefng \u0111\u1eb7c \u0111i\u1ec3m m\u00e0 Java fresher n\u00ean bi\u1ebft v\u1ec1 Java l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Java c\u00f3 5 \u0111\u1eb7c \u0111i\u1ec3m quan tr\u1ecdng m\u00e0 l\u1eadp tr\u00ecnh vi\u00ean Java fresher n\u00ean bi\u1ebft l\u00e0: h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng, th\u00f4ng d\u1ecbch, \u0111a lu\u1ed3ng, \u0111\u1ed9c l\u1eadp n\u1ec1n t\u1ea3ng v\u00e0 t\u00ednh m\u1ea1nh m\u1ebd.<\/p>\n<h3><span id=\"Cau_8_Checked_Exception_la_gi\"><strong>C\u00e2u 8: Checked Exception l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Checked Exception trong Java l\u00e0 c\u00e1c lo\u1ea1i exception m\u00e0 tr\u00ecnh bi\u00ean d\u1ecbch y\u00eau c\u1ea7u l\u1eadp tr\u00ecnh vi\u00ean ph\u1ea3i x\u1eed l\u00fd ho\u1eb7c khai b\u00e1o b\u00ean trong kh\u1ed1i m\u00e3, \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o vi\u1ec7c x\u1eed l\u00fd exception \u0111\u01b0\u1ee3c quy\u1ebft \u0111\u1ecbnh r\u00f5 r\u00e0ng. Khi s\u1eed d\u1ee5ng c\u00e1c ph\u01b0\u01a1ng th\u1ee9c ho\u1eb7c kh\u1ed1i m\u00e3 n\u00e9m ra Checked Exception, l\u1eadp tr\u00ecnh vi\u00ean bu\u1ed9c ph\u1ea3i s\u1eed d\u1ee5ng kh\u1ed1i try-catch ho\u1eb7c khai b\u00e1o s\u1eed d\u1ee5ng t\u1eeb kh\u00f3a throws \u0111\u1ec3 x\u1eed l\u00fd ngo\u1ea1i l\u1ec7 n\u00e0y.<\/p>\n<h2><span id=\"2_Nhung_cau_hoi_phong_van_Java_Collection\"><strong>2. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java Collection<\/strong><\/span><\/h2>\n<figure id=\"attachment_55172\" aria-describedby=\"caption-attachment-55172\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" class=\"size-full wp-image-55172\" src=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java.jpg\" alt=\"nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n java\" width=\"800\" height=\"533\" srcset=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java.jpg 800w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java-300x200.jpg 300w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java-150x100.jpg 150w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java-768x512.jpg 768w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java-120x80.jpg 120w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java-360x240.jpg 360w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Top-cau-hoi-phong-van-Java-600x400.jpg 600w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-55172\" class=\"wp-caption-text\"><center><em><strong>C\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java<\/strong> Collection<\/em><\/center><\/figcaption><\/figure>\n<h3><span id=\"Cau_1_Cho_biet_cac_interface_co_ban_cua_Java_Collections_framework\"><strong>C\u00e2u 1: Cho bi\u1ebft c\u00e1c interface c\u01a1 b\u1ea3n c\u1ee7a Java Collections framework?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Java Collections Framework cung c\u1ea5p 1 t\u1eadp h\u1ee3p classes v\u00e0 interface \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf nh\u1eb1m h\u1ed7 tr\u1ee3 c\u00e1c ho\u1ea1t \u0111\u1ed9ng tr\u00ean t\u1eadp h\u1ee3p c\u00e1c objects. V\u00e0 c\u00e1c interface c\u01a1 b\u1ea3n trong Java Collections Framework l\u00e0:<\/p>\n<ul>\n<li aria-level=\"1\">Collection interface<\/li>\n<li aria-level=\"1\">Set interface<\/li>\n<li aria-level=\"1\">List interface<\/li>\n<li aria-level=\"1\">Queue interface<\/li>\n<li aria-level=\"1\">Map interface<\/li>\n<\/ul>\n<h3><span id=\"Cau_2_Iterator_la_gi_trong_Java_Collection\"><strong>C\u00e2u 2: Iterator l\u00e0 g\u00ec trong Java Collection?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Iterator trong Java Collection l\u00e0 giao di\u1ec7n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 thay th\u1ebf Enumerations, v\u00e0 c\u00e1c b\u1ea1n c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng iterator \u0111\u1ec3 x\u00f3a ph\u1ea7n t\u1eed khi l\u1eb7p 1 collection, ho\u1eb7c duy\u1ec7t c\u00e1c ph\u1ea7n t\u1eed t\u1eeb \u0111\u1ea7u \u0111\u1ebfn cu\u1ed1i c\u1ee7a collection.<\/p>\n<h3><span id=\"Cau_3_Giai_thich_su_khac_nhau_giua_ListIterator_va_Iterator\"><strong>C\u00e2u 3: Gi\u1ea3i th\u00edch s\u1ef1 kh\u00e1c nhau gi\u1eefa ListIterator v\u00e0 Iterator?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong><\/p>\n<ul>\n<li aria-level=\"1\">M\u1ed9t Iterator c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng \u0111\u1ec3 duy\u1ec7t c\u00e1c List v\u00e0 Set collections; nh\u01b0ng ListIterator ch\u1ec9 c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng \u0111\u1ec3 l\u1eb7p l\u1ea1i List.<\/li>\n<li aria-level=\"1\">List tri\u1ec3n khai Iterator interface v\u00e0 c\u00f3 ch\u1ee9a c\u00e1c ch\u1ee9c n\u0103ng b\u1ed5 sung nh\u01b0 thay th\u1ebf ph\u1ea7n t\u1eed, th\u00eam ph\u1ea7n t\u1eed, l\u1ea5y v\u1ecb tr\u00ed index c\u1ee7a c\u00e1c ph\u1ea7n t\u1eed tr\u01b0\u1edbc\/ sau.<\/li>\n<li aria-level=\"1\">List c\u00f3 th\u1ec3 duy\u1ec7t collection theo 2 h\u01b0\u1edbng, c\u00f2n Iterator ch\u1ec9 duy\u1ec7t 1 collection theo h\u01b0\u1edbng chuy\u1ec3n ti\u1ebfp.<\/li>\n<\/ul>\n<h3><span id=\"Cau_4_Su_khac_nhau_giua_ArrayList_va_LinkedList_la_gi\"><strong>C\u00e2u 4: S\u1ef1 kh\u00e1c nhau gi\u1eefa ArrayList v\u00e0 LinkedList l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong><\/p>\n<table style=\"width: 777px;\">\n<tbody>\n<tr>\n<td style=\"text-align: center; width: 374.781px;\"><strong>ArrayList<\/strong><\/td>\n<td style=\"text-align: center; width: 392.219px;\"><strong>LinkedList<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 374.781px;\">ArrayList s\u1eed d\u1ee5ng m\u1ed9t m\u1ea3ng \u0111\u1ed9ng.<\/td>\n<td style=\"width: 392.219px;\">LinkedList s\u1eed d\u1ee5ng danh s\u00e1ch li\u00ean k\u1ebft doubly.<\/td>\n<\/tr>\n<tr>\n<td style=\"width: 374.781px;\">ArrayList c\u1ea7n nhi\u1ec1u chuy\u1ec3n \u0111\u1ed5i n\u00ean kh\u00f4ng hi\u1ec7u qu\u1ea3 v\u1edbi thao t\u00e1c.<\/td>\n<td style=\"width: 392.219px;\">LinkedList r\u1ea5t hi\u1ec7u qu\u1ea3 cho thao t\u00e1c.<\/td>\n<\/tr>\n<tr>\n<td style=\"width: 374.781px;\">ArrayList r\u1ea5t t\u1ed1t cho vi\u1ec7c l\u01b0u tr\u1eef v\u00e0 l\u1ea5y d\u1eef li\u1ec7u.<\/td>\n<td style=\"width: 392.219px;\">LinkedList r\u1ea5t t\u1ed1t cho vi\u1ec7c thao t\u00e1c d\u1eef li\u1ec7u.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3><span id=\"Cau_5_Phuong_thuc_hashCode_la_gi\"><strong>C\u00e2u 5: Ph\u01b0\u01a1ng th\u1ee9c hashCode() l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong><\/p>\n<ul>\n<li aria-level=\"1\">Ph\u01b0\u01a1ng th\u1ee9c hashCode() tr\u1ea3 v\u1ec1 m\u1ed9t gi\u00e1 tr\u1ecb m\u00e3 b\u0103m (m\u1ed9t s\u1ed1 nguy\u00ean).<\/li>\n<li aria-level=\"1\">N\u1ebfu 2 keys gi\u1ed1ng nhau, ph\u01b0\u01a1ng th\u1ee9c hashCode() s\u1ebd tr\u1ea3 v\u1ec1 c\u00f9ng s\u1ed1 nguy\u00ean.<\/li>\n<li aria-level=\"1\">Tuy nhi\u00ean, hai m\u00e3 b\u0103m c\u00f3 th\u1ec3 c\u00f3 c\u00e1c keys gi\u1ed1ng ho\u1eb7c kh\u00e1c nhau.<\/li>\n<\/ul>\n<h3><span id=\"Cau_6_Loi_the_cua_Properties_file_la_gi\"><strong>C\u00e2u 6: L\u1ee3i th\u1ebf c\u1ee7a Properties file l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Trong tr\u01b0\u1eddng h\u1ee3p b\u1ea1n thay \u0111\u1ed5i gi\u00e1 tr\u1ecb trong t\u1ec7p thu\u1ed9c t\u00ednh, b\u1ea1n kh\u00f4ng c\u1ea7n ph\u1ea3i bi\u00ean d\u1ecbch l\u1ea1i l\u1edbp java. V\u00ec v\u1eady, Properties file h\u1ed7 tr\u1ee3 ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 qu\u1ea3n l\u00fd \u1ee9ng d\u1ee5ng d\u1ec5 d\u00e0ng h\u01a1n.<\/p>\n<p><strong>Xem th\u00eam: <a href=\"https:\/\/jobsgo.vn\/blog\/nhung-kinh-nghiem-hay-giup-ban-vuot-qua-vong-phong-van-tuyen-dung\/\" target=\"_blank\" rel=\"noopener\">Nh\u1eefng kinh nghi\u1ec7m hay gi\u00fap b\u1ea1n v\u01b0\u1ee3t qua v\u00f2ng ph\u1ecfng v\u1ea5n tuy\u1ec3n d\u1ee5ng<\/a><\/strong><\/p>\n<h3><span id=\"Cau_7_Tai_sao_chung_ta_phai_ghi_de_phuong_thuc_equals\"><strong>C\u00e2u 7: T\u1ea1i sao ch\u00fang ta ph\u1ea3i ghi \u0111\u00e8 ph\u01b0\u01a1ng th\u1ee9c equals()?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Ch\u00fang ta ph\u1ea3i ghi \u0111\u00e8 ph\u01b0\u01a1ng th\u1ee9c equals() trong Java \u0111\u1ec3 t\u00f9y ch\u1ec9nh c\u00e1ch so s\u00e1nh hai \u0111\u1ed1i t\u01b0\u1ee3ng c\u1ee7a l\u1edbp m\u00e0 ch\u00fang ta \u0111\u1ecbnh ngh\u0129a. Ph\u01b0\u01a1ng th\u1ee9c equals() m\u1eb7c \u0111\u1ecbnh trong l\u1edbp Object so s\u00e1nh hai \u0111\u1ed1i t\u01b0\u1ee3ng b\u1eb1ng c\u00e1ch ki\u1ec3m tra xem ch\u00fang c\u00f3 tham chi\u1ebfu \u0111\u1ebfn c\u00f9ng m\u1ed9t v\u1ecb tr\u00ed b\u1ed9 nh\u1edb hay kh\u00f4ng. Tuy nhi\u00ean, \u0111\u00f4i khi ch\u00fang ta mu\u1ed1n so s\u00e1nh d\u1ef1a tr\u00ean n\u1ed9i dung c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng, kh\u00f4ng ch\u1ec9 d\u1ef1a tr\u00ean tham chi\u1ebfu. B\u1eb1ng c\u00e1ch ghi \u0111\u00e8 ph\u01b0\u01a1ng th\u1ee9c equals(), ch\u00fang ta c\u00f3 th\u1ec3 t\u1ef1 \u0111\u1ecbnh ngh\u0129a c\u00e1ch th\u1ee9c so s\u00e1nh n\u1ed9i dung c\u1ee7a hai \u0111\u1ed1i t\u01b0\u1ee3ng theo quy t\u1eafc c\u1ee7a ch\u00fang ta.<\/p>\n<h3><span id=\"Cau_8_Hash-collision_trong_Hashtable_la_gi_Va_no_duoc_xu_ly_nhu_the_nao\"><strong>C\u00e2u 8: Hash-collision trong Hashtable l\u00e0 g\u00ec? V\u00e0 n\u00f3 \u0111\u01b0\u1ee3c x\u1eed l\u00fd nh\u01b0 th\u1ebf n\u00e0o?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Hash-collision trong Hashtable x\u1ea3y ra khi hai ho\u1eb7c nhi\u1ec1u kh\u00f3a kh\u00e1c nhau \u0111\u01b0\u1ee3c \u00e1nh x\u1ea1 v\u00e0o c\u00f9ng m\u1ed9t v\u1ecb tr\u00ed b\u1ed9 nh\u1edb. Hashtable gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1 n\u00e0y b\u1eb1ng c\u00e1ch s\u1eed d\u1ee5ng chaining, t\u1ee9c l\u00e0 l\u01b0u c\u00e1c kh\u00f3a v\u00e0 gi\u00e1 tr\u1ecb t\u1ea1i c\u00f9ng m\u1ed9t v\u1ecb tr\u00ed trong m\u1ed9t danh s\u00e1ch li\u00ean k\u1ebft.<\/p>\n<h2><span id=\"3_Nhung_cau_hoi_phong_van_JavaScript\"><strong>3. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n JavaScript<\/strong><\/span><\/h2>\n<p>JavaScript \u0111ang tr\u1edf th\u00e0nh m\u1ed9t trong nh\u1eefng lo\u1ea1i ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh ph\u1ed5 bi\u1ebfn nh\u1ea5t th\u1ebf gi\u1edbi. Do \u0111\u00f3, tr\u01b0\u1edbc khi \u0111i ph\u1ecfng v\u1ea5n b\u1ea1n c\u1ea7n chu\u1ea9n b\u1ecb th\u1eadt k\u1ef9 c\u00e2u tr\u1ea3 l\u1eddi cho c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n JavaScript.<\/p>\n<figure id=\"attachment_55173\" aria-describedby=\"caption-attachment-55173\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" class=\"size-full wp-image-55173\" src=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Cac-Cau-Hoi-Phong-Van-Java-Thuong-Gap.jpg\" alt=\"nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n java\" width=\"800\" height=\"443\" srcset=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Cac-Cau-Hoi-Phong-Van-Java-Thuong-Gap.jpg 800w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Cac-Cau-Hoi-Phong-Van-Java-Thuong-Gap-300x166.jpg 300w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Cac-Cau-Hoi-Phong-Van-Java-Thuong-Gap-150x83.jpg 150w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Cac-Cau-Hoi-Phong-Van-Java-Thuong-Gap-768x425.jpg 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-55173\" class=\"wp-caption-text\"><center><em>C\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n JavaScript<\/em><\/center><\/figcaption><\/figure>\n<h3><span id=\"Cau_1_Prototypal_inheritance_va_classical_inheritance_trong_JavaScript_la_gi\"><strong>C\u00e2u 1: Prototypal inheritance v\u00e0 classical inheritance trong JavaScript l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong><\/p>\n<ul>\n<li aria-level=\"1\">Prototypal inheritance l\u00e0 s\u1ef1 k\u1ebf th\u1eeba nguy\u00ean m\u1eabu, c\u00e1c phi\u00ean b\u1ea3n c\u1ee7a prototypal inheritance c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c t\u1ea1o ra t\u1eeb nhi\u1ec1u \u0111\u1ed1i t\u01b0\u1ee3ng kh\u00e1c nhau, \u0111\u1eb7c bi\u1ec7t n\u00f3 c\u00f2n cho ph\u00e9p vi\u1ec7c k\u1ebf th\u1eeba c\u00f3 ch\u1ecdn l\u1ecdc.<\/li>\n<li aria-level=\"1\">Class Inheritance l\u00e0 t\u00ednh k\u1ebf th\u1eeba l\u1edbp, cho ph\u00e9p x\u00e2y d\u1ef1ng l\u1edbp m\u1edbi tr\u00ean c\u00e1c \u0111\u1ecbnh ngh\u0129a c\u1ee7a l\u1edbp c\u00f3 s\u1eb5n. Ngh\u0129a l\u00e0, l\u1edbp cha s\u1ebd chia s\u1ebb ph\u01b0\u01a1ng th\u1ee9c, d\u1eef li\u1ec7u cho l\u1edbp con.<\/li>\n<\/ul>\n<h3><span id=\"Cau_2_Lap_trinh_khong_dong_bo_trong_JavaScript_la_gi\"><strong>C\u00e2u 2: L\u1eadp tr\u00ecnh kh\u00f4ng \u0111\u1ed3ng b\u1ed9 trong JavaScript l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> L\u00e0 vi\u1ec7c lo\u1ea1i b\u1ecf l\u1ec7nh, \u0111i\u1ec1u ki\u1ec7n g\u1ecdi h\u00e0m, m\u00e3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n theo tr\u00ecnh t\u1ef1 t\u1eeb tr\u00ean xu\u1ed1ng d\u01b0\u1edbi, \u0111\u1ed3ng th\u1eddi ng\u0103n ch\u1eb7n c\u00e1c t\u00e1c v\u1ee5 ch\u1ea1y d\u00e0i.<\/p>\n<h3><span id=\"Cau_3_Functional_programming_la_gi\"><strong>C\u00e2u 3: Functional programming l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Functional programming l\u00e0 d\u1ea1ng m\u00f4 h\u00ecnh l\u1eadp tr\u00ecnh tr\u00ean h\u00e0m to\u00e1n h\u1ecdc nh\u1eb1m tr\u00e1nh thay \u0111\u1ed5i c\u1ee7a gi\u00e1 tr\u1ecb d\u1eef li\u1ec7u; v\u00e0 t\u1ed1i \u0111a h\u00f3a kh\u1ea3 n\u0103ng t\u00e1i s\u1eed d\u1ee5ng trong ch\u01b0\u01a1ng tr\u00ecnh.<\/p>\n<h3><span id=\"Cau_4_Co_bao_nhieu_kieu_du_lieu_trong_JavaScript\"><strong>C\u00e2u 4: C\u00f3 bao nhi\u00eau ki\u1ec3u d\u1eef li\u1ec7u trong JavaScript?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> JavaScript c\u00f3 6 ki\u1ec3u d\u1eef li\u1ec7u, c\u1ee5 th\u1ec3 l\u00e0:<\/p>\n<ul>\n<li aria-level=\"1\">String<\/li>\n<li aria-level=\"1\">Number<\/li>\n<li aria-level=\"1\">Object<\/li>\n<li aria-level=\"1\">Undefined<\/li>\n<li aria-level=\"1\">Boolean<\/li>\n<li aria-level=\"1\">Array<\/li>\n<li aria-level=\"1\">Null<\/li>\n<\/ul>\n<h3><span id=\"Cau_5_Phan_biet_var_let_va_const\"><strong>C\u00e2u 5: Ph\u00e2n bi\u1ec7t var, let v\u00e0 const?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> S\u1ef1 kh\u00e1c nhau gi\u1eefa var, let v\u00e0 const l\u00e0:<\/p>\n<ul>\n<li aria-level=\"1\">const: l\u00e0 h\u1eb1ng s\u1ed1. \u0110\u00e2y l\u00e0 gi\u00e1 tr\u1ecb kh\u00f4ng \u0111\u1ed5i trong su\u1ed1t qu\u00e1 tr\u00ecnh ch\u1ea1y.<\/li>\n<li aria-level=\"1\">let: t\u1ea1o ra m\u1ed9t bi\u1ebfn m\u00e0 bi\u1ebfn n\u00e0y ch\u1ec9 c\u00f3 th\u1ec3 truy c\u1eadp \u0111\u01b0\u1ee3c trong block bao quanh n\u00f3.<\/li>\n<li aria-level=\"1\">var: t\u1ea1o ra m\u1ed9t bi\u1ebfn c\u00f3 th\u1ec3 truy c\u1eadp xuy\u00ean su\u1ed1t function ch\u1ee9a n\u00f3.<\/li>\n<\/ul>\n<h3><span id=\"Cau_6_Strict_mode_trong_javascript_la_gi\"><strong>C\u00e2u 6: Strict mode trong javascript l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Strict Mode \u0111\u01b0\u1ee3c hi\u1ec3u l\u00e0 m\u1ed9t m\u1eabu nghi\u00eam kh\u1eafc trong Javascript. T\u1ee9c l\u00e0, so v\u1edbi vi\u1ec7c vi\u1ebft code b\u00ecnh th\u01b0\u1eddng (Normal Mode), s\u1eed d\u1ee5ng Strict Mode s\u1ebd c\u1ea7n tu\u00e2n th\u1ee7 th\u00eam m\u1ed9t s\u1ed1 quy \u0111\u1ecbnh kh\u00e1c.<\/p>\n<p><strong>Xem th\u00eam: T\u1ed5ng h\u1ee3p c\u00e1c <a href=\"https:\/\/jobsgo.vn\/blog\/cau-hoi-phong-van-front-end\/\" target=\"_blank\" rel=\"noopener\">c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n front end<\/a><\/strong><\/p>\n<h3><span id=\"Cau_7_Anonymous_function_la_gi\"><strong>C\u00e2u 7: Anonymous function l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Anonymous function (h\u00e0m v\u00f4 danh) trong Java l\u00e0 m\u1ed9t h\u00e0m kh\u00f4ng c\u00f3 t\u00ean \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a v\u00e0 s\u1eed d\u1ee5ng ngay t\u1ea1i ch\u1ed7 m\u00e0 kh\u00f4ng c\u1ea7n ph\u1ea3i khai b\u00e1o trong m\u1ed9t l\u1edbp ri\u00eang. N\u00f3 cung c\u1ea5p m\u1ed9t c\u00e1ch ti\u1ec7n l\u1ee3i \u0111\u1ec3 tri\u1ec3n khai c\u00e1c ph\u01b0\u01a1ng th\u1ee9c nhanh ch\u00f3ng v\u00e0 tr\u1ef1c ti\u1ebfp trong m\u1ed9t \u0111o\u1ea1n m\u00e3, th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong ng\u1eef c\u1ea3nh c\u1ee7a c\u00e1c giao di\u1ec7n h\u00e0m (functional interfaces) ho\u1eb7c khi c\u1ea7n tri\u1ec3n khai c\u00e1c \u0111o\u1ea1n m\u00e3 ng\u1eafn v\u00e0 \u0111\u01a1n gi\u1ea3n.<\/p>\n<h3><span id=\"Cau_8_Ham_Arraysplice_va_ham_Arrayslice_khac_nhau_nhu_the_nao\"><strong>C\u00e2u 8: H\u00e0m Array.splice() v\u00e0 h\u00e0m Array.slice() kh\u00e1c nhau nh\u01b0 th\u1ebf n\u00e0o?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Array.splice() \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 thay \u0111\u1ed5i m\u1ea3ng ban \u0111\u1ea7u b\u1eb1ng c\u00e1ch ch\u00e8n ho\u1eb7c x\u00f3a ph\u1ea7n t\u1eed, c\u00f2n Array.slice() t\u1ea1o ra m\u1ed9t b\u1ea3n sao c\u1ee7a m\u1ea3ng ban \u0111\u1ea7u b\u1eb1ng c\u00e1ch tr\u00edch xu\u1ea5t m\u1ed9t ph\u1ea7n t\u1eed con.<\/p>\n<h2><span id=\"4_Nhung_cau_hoi_phong_van_Java_Spring\"><strong>4.<\/strong> <strong>Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java Spring<\/strong><\/span><\/h2>\n<figure id=\"attachment_55174\" aria-describedby=\"caption-attachment-55174\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" class=\"size-full wp-image-55174\" src=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-core.jpg\" alt=\"nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n java\" width=\"800\" height=\"437\" srcset=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-core.jpg 800w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-core-300x164.jpg 300w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-core-150x82.jpg 150w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/cau-hoi-phong-van-java-core-768x420.jpg 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-55174\" class=\"wp-caption-text\"><center><em>C\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java Spring<\/em><\/center><\/figcaption><\/figure>\n<h3><span id=\"Cau_1_The_nao_Spring_trong_Java\"><strong>C\u00e2u 1: Th\u1ebf n\u00e0o Spring trong Java?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Spring trong Java l\u00e0 khung Framework c\u00f3 m\u00e3 ngu\u1ed3n m\u1edf v\u00e0 Spring \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1ec3 l\u1eadp tr\u00ecnh Java t\u1ea1o ra nh\u1eefng \u1ee9ng d\u1ee5ng website b\u1ea5t k\u1ef3.<\/p>\n<h3><span id=\"Cau_2_Hien_nay_Java_Spring_co_bao_nhieu_phien_ban\"><strong>C\u00e2u 2: Hi\u1ec7n nay Java Spring c\u00f3 bao nhi\u00eau phi\u00ean b\u1ea3n?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Java Spring c\u00f3 3 phi\u00ean b\u1ea3n ph\u1ed5 bi\u1ebfn l\u00e0 Spring 4.0, Spring 3.0, Spring 2.5. Ngo\u00e0i ra, n\u1ebfu nh\u00e0 tuy\u1ec3n d\u1ee5ng h\u1ecfi v\u1ec1 1 phi\u00ean b\u1ea3n c\u1ee5 th\u1ec3 th\u00ec b\u1ea1n m\u1edbi tr\u1ea3 l\u1eddi chi ti\u1ebft, tr\u00e1nh tr\u1ea3 l\u1eddi d\u00e0i d\u00f2ng, m\u1ea5t th\u1eddi gian c\u1ee7a 2 b\u00ean.<\/p>\n<h3><span id=\"Cau_3_Spring_Boot_la_gi\"><strong>C\u00e2u 3: Spring Boot l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Java Spring Boot l\u00e0 phi\u00ean b\u1ea3n trong Spring, n\u00f3 gi\u00fap cho c\u00e1c \u1ee9ng d\u1ee5ng \u0111\u01b0\u1ee3c t\u1ea1o ra c\u00f3 quy tr\u00ecnh s\u1eafp x\u1ebfp d\u1eef li\u1ec7u h\u1ee3p l\u00fd h\u01a1n. \u0110\u1eb7c bi\u1ec7t, Spring Boot c\u00f2n c\u00f3 t\u00ednh n\u0103ng lo\u1ea1i b\u1ecf nhu c\u1ea7u x\u00e1c \u0111\u1ecbnh c\u1ea5u h\u00ecnh b\u1ea3n m\u1eabu.<\/p>\n<h3><span id=\"Cau_4_Loi_the_cua_Java_Spring_la_gi\"><strong>C\u00e2u 4: L\u1ee3i th\u1ebf c\u1ee7a Java Spring l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> \u0110\u00e2y l\u00e0 <strong>c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java<\/strong> c\u00f3 t\u00ednh ch\u1ea5t kh\u00e1 ch\u1ee7 quan, n\u00f3 d\u1ef1a tr\u00ean quan \u0111i\u1ec3m m\u1ed7i ng\u01b0\u1eddi khi s\u1eed d\u1ee5ng \u0111\u1ec3 l\u1eadp tr\u00ecnh. C\u00e1c b\u1ea1n c\u00f3 th\u1ec3 tr\u1ea3 l\u1eddi l\u1ee3i th\u1ebf c\u1ee7a Java Spring l\u00e0 s\u1eed d\u1ee5ng d\u1ec5 d\u00e0ng, m\u00e3 ngu\u1ed3n m\u1edf, d\u1ec5 ki\u1ec3m tra v\u00e0 c\u00f3 c\u00e1c m\u1eabu s\u1eb5n,\u2026<\/p>\n<h3><span id=\"Cau_5_Spring_co_bao_nhieu_module_khac_nhau\"><strong>C\u00e2u 5: Spring c\u00f3 bao nhi\u00eau module kh\u00e1c nhau?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> \u0110\u00e2y l\u00e0 m\u1ed9t trong nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java Spring th\u01b0\u1eddng g\u1eb7p. B\u1ea1n c\u00f3 th\u1ec3 tr\u1ea3 l\u1eddi l\u00e0 Java Spring c\u00f3 kho\u1ea3ng 20 modun v\u00e0 n\u00f3 \u0111\u01b0\u1ee3c ph\u00e2n chia th\u00e0nh c\u00e1c v\u00f9ng ch\u1ee9a ri\u00eang bi\u1ec7t nh\u01b0 Web, Test, Core, Data Access Container,\u2026<\/p>\n<h3><span id=\"Cau_6_IOC_la_gi\"><strong>C\u00e2u 6: IOC l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> IOC l\u00e0 t\u00ean vi\u1ebft t\u1eaft c\u1ee7a c\u1ee5m t\u1eeb Inversion of Control. C\u00f3 th\u1ec3 hi\u1ec3u, n\u00f3 l\u00e0 Core Container c\u1ee7a Java Spring. IOC qu\u1ea3n l\u00fd v\u00e0 \u0111\u1ecbnh c\u1ea5u h\u00ecnh c\u00e1c \u1ee9ng d\u1ee5ng t\u00edch h\u1ee3p kh\u00e1c nhau th\u00f4ng qua ph\u00e9p Dependency Injection \u0111\u1ec3. Java Spring hi\u1ec7n c\u00f3 2 lo\u1ea1i IOC l\u00e0 ApplicationContext v\u00e0 BeanFactory.<\/p>\n<h3><span id=\"Cau_7_Co_bao_nhieu_cach_de_thuc_hien_Dependency_Injection\"><strong>C\u00e2u 7: C\u00f3 bao nhi\u00eau c\u00e1ch \u0111\u1ec3 th\u1ef1c hi\u1ec7n Dependency Injection?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Dependency c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n b\u1eb1ng 3 c\u00e1ch sau:<\/p>\n<ul>\n<li aria-level=\"1\">S\u1eed d\u1ee5ng Constructor Injection<\/li>\n<li aria-level=\"1\">S\u1eed d\u1ee5ng Setter Injection<\/li>\n<li aria-level=\"1\">S\u1eed d\u1ee5ng Interface Injection<\/li>\n<\/ul>\n<p>Trong \u0111\u00f3, Constructor v\u00e0 Setter Injection \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng nhi\u1ec1u nh\u1ea5t trong Spring framework.<\/p>\n<h3><span id=\"Cau_8_XML_file_la_gi\"><strong>C\u00e2u 8: XML file l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> XML l\u00e0 m\u1ed9t t\u1ec7p c\u1ea5u h\u00ecnh Spring. T\u1ea5t c\u1ea3 th\u00f4ng tin v\u1ec1 c\u00e1c lo\u1ea1i l\u1edbp kh\u00e1c nhau c\u0169ng nh\u01b0 m\u1ed1i t\u01b0\u01a1ng quan c\u1ee7a ch\u00fang \u0111\u1ec1u \u0111\u01b0\u1ee3c ch\u1ee9a trong XML file.<\/p>\n<h2><span id=\"5_Nhung_cau_hoi_phong_van_huong_doi_tuong_OOP\"><strong>5. Nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng OOP<\/strong><\/span><\/h2>\n<figure id=\"attachment_55175\" aria-describedby=\"caption-attachment-55175\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" class=\"size-full wp-image-55175\" src=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Tuyen-tap-nhung-cau-hoi-phong-van-Java-thuong-gap.jpg\" alt=\"nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n java\" width=\"800\" height=\"450\" srcset=\"https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Tuyen-tap-nhung-cau-hoi-phong-van-Java-thuong-gap.jpg 800w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Tuyen-tap-nhung-cau-hoi-phong-van-Java-thuong-gap-300x169.jpg 300w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Tuyen-tap-nhung-cau-hoi-phong-van-Java-thuong-gap-150x84.jpg 150w, https:\/\/media-blog.jobsgo.vn\/blog\/wp-content\/uploads\/2021\/08\/Tuyen-tap-nhung-cau-hoi-phong-van-Java-thuong-gap-768x432.jpg 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><figcaption id=\"caption-attachment-55175\" class=\"wp-caption-text\"><center><em>C\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng OOP<\/em><\/center><\/figcaption><\/figure>\n<h3><span id=\"Cau_1_Lap_trinh_huong_doi_tuong_OOP_gom_nhung_gi\"><strong>C\u00e2u 1: L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng OOP g\u1ed3m nh\u1eefng g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> B\u1ea1n c\u00f3 th\u1ec3 tr\u1ea3 l\u1eddi m\u1ed9t c\u00e1ch \u0111\u01a1n gi\u1ea3n l\u00e0 l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng bao g\u1ed3m Composition, Association, Encapsulation, Aggregation, Inheritance, Abstraction,\u2026<\/p>\n<h3><span id=\"Cau_2_Da_hinh_la_gi_Co_may_loai_da_hinh\"><strong>C\u00e2u 2: \u0110a h\u00ecnh l\u00e0 g\u00ec? C\u00f3 m\u1ea5y lo\u1ea1i \u0111a h\u00ecnh?<\/strong><\/span><\/h3>\n<p><a rel=\"nofollow\" href=\"https:\/\/en.wikipedia.org\/wiki\/Job_interview#Types_of_questions\"><strong>C\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n<\/strong><\/a> Java n\u00e0y nghe c\u00f3 v\u1ebb \u0111\u01a1n gi\u1ea3n, nh\u01b0ng n\u1ebfu b\u1ea1n bi\u1ebft c\u00e1ch kh\u00e1i qu\u00e1t th\u00ec b\u1ea1n s\u1ebd \u0111\u01b0\u1ee3c nh\u00e0 tuy\u1ec3n d\u1ee5ng \u0111\u00e1nh gi\u00e1 r\u1ea5t cao.<\/p>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> \u0110a h\u00ecnh l\u00e0 kh\u1ea3 n\u0103ng \u0111\u1ecbnh ngh\u0129a ph\u01b0\u01a1ng th\u1ee9c t\u1ea1i giai \u0111o\u1ea1n runtime; v\u00e0 c\u00f3 2 lo\u1ea1i \u0111a h\u00ecnh ph\u1ed5 bi\u1ebfn l\u00e0 Overriding v\u00e0 Overloading:<\/p>\n<ul>\n<li aria-level=\"1\">Overloading: L\u00e0 \u0111a h\u00ecnh trong th\u1eddi gian bi\u00ean d\u1ecbch, l\u00e0 k\u1ef9 thu\u1eadt cho ph\u00e9p trong c\u00f9ng 1 class s\u1ebd c\u00f3 th\u1ec3 c\u00f3 nhi\u1ec1u ph\u01b0\u01a1ng th\u1ee9c c\u00f9ng t\u00ean nh\u01b0ng s\u1ebd kh\u00e1c nhau v\u1ec1 ki\u1ec3u d\u1eef li\u1ec7u ho\u1eb7c s\u1ed1 l\u01b0\u1ee3ng tham s\u1ed1.<\/li>\n<li aria-level=\"1\">Overriding: L\u00e0 \u0111a h\u00ecnh trong th\u1eddi gian ch\u1ea1y, n\u00f3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong tr\u01b0\u1eddng h\u1ee3p l\u1edbp con k\u1ebf th\u1eeba t\u1eeb l\u1edbp cha, \u0111\u1ecbnh ngh\u0129a l\u1ea1i ph\u01b0\u01a1ng th\u1ee9c c\u00f3 m\u1eb7t \u1edf l\u1edbp cha.<\/li>\n<\/ul>\n<h3><span id=\"Cau_3_Java_8_co_nhung_tinh_nang_quan_trong_nao\"><strong>C\u00e2u 3: Java 8 c\u00f3 nh\u1eefng t\u00ednh n\u0103ng quan tr\u1ecdng n\u00e0o?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Nh\u1eefng t\u00ednh n\u0103ng quan tr\u1ecdng trong Java 8 c\u00f3 th\u1ec3 k\u1ec3 \u0111\u1ebfn l\u00e0: Bi\u1ec3u th\u1ee9c Lambda; ph\u01b0\u01a1ng th\u1ee9c forEach; Java time API; Stream API; Static v\u00e0 method; c\u1ea3i ti\u1ebfn Core API, Java IO, Collection API, Concurrency API,\u2026<\/p>\n<h3><span id=\"Cau_4_Cac_tinh_chat_cua_huong_doi_tuong_la_gi\"><strong>C\u00e2u 4: C\u00e1c t\u00ednh ch\u1ea5t c\u1ee7a h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 g\u00ec?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng bao g\u1ed3m 4 t\u00ednh ch\u1ea5t sau:<\/p>\n<ul>\n<li aria-level=\"1\">T\u00ednh \u0111\u00f3ng g\u00f3i<\/li>\n<li aria-level=\"1\">T\u00cdnh k\u1ebf th\u1eeba<\/li>\n<li aria-level=\"1\">T\u00ednh tr\u1eebu t\u01b0\u1ee3ng<\/li>\n<li aria-level=\"1\">T\u00ednh \u0111a h\u00ecnh<\/li>\n<\/ul>\n<h3><span id=\"Cau_5_Co_may_loai_access_modifier_Phan_biet_su_khac_nhau_giua_chung\"><strong>C\u00e2u 5: C\u00f3 m\u1ea5y lo\u1ea1i access modifier? Ph\u00e2n bi\u1ec7t s\u1ef1 kh\u00e1c nhau gi\u1eefa ch\u00fang?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> C\u00f3 4 lo\u1ea1i Access Modifier v\u00e0 m\u1ed7i lo\u1ea1i c\u00f3 nh\u1eefng t\u00ednh n\u0103ng kh\u00e1c nhau:<\/p>\n<ul>\n<li aria-level=\"1\">Private: Ch\u1ec9 cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng truy c\u1eadp trong c\u00f9ng class.<\/li>\n<li aria-level=\"1\">Default: Ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 truy c\u1eadp trong c\u00f9ng class v\u00e0 package.<\/li>\n<li aria-level=\"1\">Protected: C\u00f3 th\u1ec3 truy c\u1eadp trong c\u00f9ng class, package v\u00e0 ngo\u00e0i package b\u1edfi l\u1edbp con.<\/li>\n<li aria-level=\"1\">Public: Cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng truy c\u1eadp \u1edf m\u1ecdi n\u01a1i.<\/li>\n<\/ul>\n<h3><span id=\"Cau_6_Interface_co_the_la_final_khong\"><strong>C\u00e2u 6: Interface c\u00f3 th\u1ec3 l\u00e0 final kh\u00f4ng?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Interface kh\u00f4ng th\u1ec3 l\u00e0 final v\u00ec c\u1ea7n ph\u1ea3i c\u00f3 m\u1ed9t l\u1edbp implement interface th\u00ec m\u1edbi s\u1eed d\u1ee5ng \u0111\u01b0\u1ee3c.<\/p>\n<h3><span id=\"Cau_7_The_nao_la_tinh_dong_goi\"><strong>C\u00e2u 7: Th\u1ebf n\u00e0o l\u00e0 t\u00ednh \u0111\u00f3ng g\u00f3i?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> T\u00ednh \u0111\u00f3ng g\u00f3i (encapsulation) trong l\u1eadp tr\u00ecnh l\u00e0 m\u1ed9t nguy\u00ean t\u1eafc thi\u1ebft k\u1ebf cho ph\u00e9p \u1ea9n th\u00f4ng tin v\u00e0 gi\u1edbi h\u1ea1n truy c\u1eadp tr\u1ef1c ti\u1ebfp v\u00e0o c\u00e1c th\u00e0nh ph\u1ea7n d\u1eef li\u1ec7u v\u00e0 ph\u01b0\u01a1ng th\u1ee9c c\u1ee7a m\u1ed9t \u0111\u1ed1i t\u01b0\u1ee3ng. N\u00f3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng d\u1eef li\u1ec7u v\u00e0 h\u00e0nh vi c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng ch\u1ec9 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c truy c\u1eadp th\u00f4ng qua c\u00e1c ph\u01b0\u01a1ng th\u1ee9c c\u00f4ng khai (public methods) \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a, t\u1eeb \u0111\u00f3 \u0111\u1ea3m b\u1ea3o t\u00ednh ri\u00eang t\u01b0 v\u00e0 ki\u1ec3m so\u00e1t h\u1ee3p l\u00fd trong vi\u1ec7c s\u1eed d\u1ee5ng v\u00e0 thay \u0111\u1ed5i d\u1eef li\u1ec7u.<\/p>\n<h3><span id=\"Cau_8_Co_bat_buoc_phai_khai_bao_constructor_trong_lop\"><strong>C\u00e2u 8: C\u00f3 b\u1eaft bu\u1ed9c ph\u1ea3i khai b\u00e1o constructor trong l\u1edbp?<\/strong><\/span><\/h3>\n<p><strong>Tr\u1ea3 l\u1eddi:<\/strong> Kh\u00f4ng b\u1eaft bu\u1ed9c ph\u1ea3i khai b\u00e1o constructor trong m\u1ed9t l\u1edbp. N\u1ebfu l\u1edbp kh\u00f4ng c\u00f3 constructor \u0111\u01b0\u1ee3c khai b\u00e1o, Java s\u1ebd t\u1ef1 \u0111\u1ed9ng t\u1ea1o m\u1ed9t constructor m\u1eb7c \u0111\u1ecbnh (default constructor) kh\u00f4ng c\u00f3 tham s\u1ed1. Tuy nhi\u00ean, khi l\u1edbp c\u00f3 nhu c\u1ea7u thi\u1ebft l\u1eadp c\u00e1c gi\u00e1 tr\u1ecb ban \u0111\u1ea7u cho c\u00e1c thu\u1ed9c t\u00ednh c\u1ee7a n\u00f3 ho\u1eb7c c\u1ea7n th\u1ef1c hi\u1ec7n c\u00e1c thao t\u00e1c kh\u00e1c trong qu\u00e1 tr\u00ecnh kh\u1edfi t\u1ea1o, l\u1eadp tr\u00ecnh vi\u00ean c\u00f3 th\u1ec3 t\u1ef1 \u0111\u1ecbnh ngh\u0129a constructor \u0111\u1ec3 \u0111\u00e1p \u1ee9ng c\u00e1c y\u00eau c\u1ea7u c\u1ee5 th\u1ec3 c\u1ee7a l\u1edbp.<\/p>\n<p>Tr\u00ean \u0111\u00e2y <a href=\"https:\/\/jobsgo.vn\/\" target=\"_blank\" rel=\"noopener\"><strong>JobsGO<\/strong><\/a> \u0111\u00e3 chia s\u1ebb v\u1edbi b\u1ea1n \u0111\u1ecdc b\u1ed9 nh\u1eefng <strong>c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java<\/strong> th\u01b0\u1eddng g\u1eb7p. H\u00e3y nh\u1edb r\u1eb1ng, trong qu\u00e1 tr\u00ecnh ph\u1ecfng v\u1ea5n b\u1ea1n ch\u1ec9 c\u1ea7n tr\u1ea3 l\u1eddi \u0111\u00fang tr\u1ecdng t\u00e2m v\u00e0 b\u00e1m s\u00e1t v\u00e0o c\u00e2u h\u1ecfi l\u00e0 c\u00f3 th\u1ec3 chinh ph\u1ee5c \u0111\u01b0\u1ee3c c\u00e1c nh\u00e0 tuy\u1ec3n d\u1ee5ng.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>5\/5 &#8211; (1 vote) B\u1ea1n \u0111ang chu\u1ea9n b\u1ecb tham gia bu\u1ed5i ph\u1ecfng v\u1ea5n Java th\u00ec vi\u1ec7c chu\u1ea9n b\u1ecb nh\u1eefng c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java l\u00e0 v\u00f4 c\u00f9ng c\u1ea7n thi\u1ebft. V\u00ec th\u1ebf, JobsGO \u0111\u00e3 t\u1ed5ng h\u1ee3p b\u1ed9 c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n&#8230;<\/p>\n","protected":false},"author":43,"featured_media":55171,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_yoast_wpseo_focuskw":"c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n java","_yoast_wpseo_title":"Top 35+ c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java ph\u1ed5 bi\u1ebfn nh\u1ea5t b\u1ea1n n\u00ean tham kh\u1ea3o %%sep%% %%sitename%%","_yoast_wpseo_metadesc":"C\u00f9ng t\u00ecm hi\u1ec3u 35+ c\u00e1c c\u00e2u h\u1ecfi ph\u1ecfng v\u1ea5n Java th\u01b0\u1eddng g\u1eb7p nh\u1ea5t \u1edf c\u00e1c bu\u1ed5i ph\u1ecfng v\u1ea5n xin vi\u1ec7c trong b\u00e0i vi\u1ebft sau nh\u00e9! 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