{"id":4681,"date":"2019-10-30T19:27:32","date_gmt":"2019-10-30T10:27:32","guid":{"rendered":"https:\/\/chat-messenger.com\/?p=4681"},"modified":"2019-10-30T19:38:47","modified_gmt":"2019-10-30T10:38:47","slug":"array_copy_clone","status":"publish","type":"post","link":"https:\/\/chat-messenger.com\/vi\/blog\/java\/mang_copy_clone","title":{"rendered":"T\u1ed5ng h\u1ee3p c\u00e1c thao t\u00e1c m\u1ea3ng c\u01a1 b\u1ea3n trong Java"},"content":{"rendered":"<h2>Kh\u1edfi t\u1ea1o m\u1ea3ng c\u00f9ng l\u00fac v\u1edbi vi\u1ec7c khai b\u00e1o<\/h2>\n<p>B\u1ea1n c\u00f3 th\u1ec3 kh\u1edfi t\u1ea1o m\u1ed9t m\u1ea3ng c\u00f9ng l\u00fac v\u1edbi vi\u1ec7c khai b\u00e1o b\u1eb1ng c\u00e1ch vi\u1ebft:<\/p>\n<h4>m\u00e3 m\u1eabu<\/h4>\n<pre class=\"sample_src\">\r\nstatic void arraySample() { String[] s = {&quot;Apple&quot;, &quot;Orange&quot;, &quot;Banana&quot;}; } System.out.println(s[1]);\r\n<\/pre>\n<p>K\u1ebft qu\u1ea3 \u0111\u1ea7u ra:<\/p>\n<pre class=\"console\">\r\ncam qu\u00fdt\r\n<\/pre>\n<p><script type=\"text\/javascript\" src=\"https:\/\/chat-messenger.com\/js\/common.js?dd12sssas2223\" charset=\"UTF-8\"><\/script><br \/>\n<script type=\"text\/javascript\"> writePR(); <\/script><\/p>\n<h2>L\u1ea5y s\u1ed1 ph\u1ea7n t\u1eed trong m\u1ed9t m\u1ea3ng \u2013 <strong>chi\u1ec1u d\u00e0i<\/strong><\/h2>\n<p>N\u1ebfu b\u1ea1n mu\u1ed1n l\u1ea5y s\u1ed1 ph\u1ea7n t\u1eed trong m\u1ed9t m\u1ea3ng, h\u00e3y s\u1eed d\u1ee5ng \u0111\u1ed9 d\u00e0i. Xin l\u01b0u \u00fd r\u1eb1ng \u0111\u1ed9 d\u00e0i l\u00e0 m\u1ed9t tr\u01b0\u1eddng ch\u1ee9 kh\u00f4ng ph\u1ea3i m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c.<\/p>\n<h4>m\u00e3 m\u1eabu<\/h4>\n<pre class=\"sample_src\">\r\nstatic void lengthSample() { String[] s1 = {&quot;apple&quot;, &quot;orange&quot;, &quot;grape&quot;}; String[] s2 = {}; System.out.println(s1.length); System.out.println( s2.length); }\r\n<\/pre>\n<p>K\u1ebft qu\u1ea3 \u0111\u1ea7u ra:<\/p>\n<pre class=\"console\">\r\n3\r\n0\r\n<\/pre>\n<h2>Sao ch\u00e9p m\u1ed9t m\u1ea3ng \u2013 <strong>d\u00f2ng v\u00f4 t\u00ednh<\/strong><\/h2>\n<p>B\u1ea3n sao r\u1ea5t h\u1eefu \u00edch khi b\u1ea1n mu\u1ed1n t\u1ea1o m\u1ed9t m\u1ea3ng gi\u1ed1ng v\u1edbi m\u1ed9t m\u1ea3ng kh\u00e1c.<\/p>\n<h4>m\u00e3 m\u1eabu<\/h4>\n<pre class=\"sample_src\">\r\nstatic void cloneSample() { String[] s1 = {&quot;apple&quot;, &quot;orange&quot;, &quot;grape&quot;}; String[] s2 = s1.clone(); System.out.println(s1[0] + &#039; &#039; + s1[1] + &#039; &#039; + s1[2]); System.out.println(s2[0] + &#039; &#039; + s2[1] + &#039; &#039; + s2[2]); }\r\n<\/pre>\n<p>K\u1ebft qu\u1ea3 \u0111\u1ea7u ra:<\/p>\n<pre class=\"console\">\r\nT\u00e1o Cam Nho T\u00e1o Cam Nho Nho\r\n<\/pre>\n<h2>Sao ch\u00e9p m\u1ed9t m\u1ea3ng \u2013 <strong>System.arraycopy<\/strong><\/h2>\n<p>M\u1ea3ng Java c\u00f3 k\u00edch th\u01b0\u1edbc c\u1ed1 \u0111\u1ecbnh khi kh\u1edfi t\u1ea1o. N\u1ebfu b\u1ea1n mu\u1ed1n t\u0103ng k\u00edch th\u01b0\u1edbc c\u1ee7a m\u1ed9t m\u1ea3ng sau khi \u0111\u01b0\u1ee3c t\u1ea1o, b\u1ea1n c\u1ea7n s\u1eed d\u1ee5ng System.arraycopy.<\/p>\n<p>arraycopy \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 sao ch\u00e9p m\u1ed9t m\u1ea3ng gi\u1ed1ng nh\u01b0 b\u1ea3n sao, nh\u01b0ng n\u00f3 cho ph\u00e9p c\u00e0i \u0111\u1eb7t chi ti\u1ebft h\u01a1n b\u1ea3n sao.<\/p>\n<pre class=\"point\">\r\narraycopy(Object src, int srcPos, Object dest, int destPos, int length) src...Sao ch\u00e9p m\u1ea3ng ngu\u1ed3n srcPos...Sao ch\u00e9p m\u1ea3ng ngu\u1ed3n (src) v\u1ecb tr\u00ed b\u1eaft \u0111\u1ea7u \u0111\u1ec3 sao ch\u00e9p dest...Sao ch\u00e9p m\u1ea3ng \u0111\u00edch destPos. ..Start v\u1ecb tr\u00ed c\u1ea7n sao ch\u00e9p trong b\u1ea3n sao \u0111\u1ed9 d\u00e0i m\u1ea3ng \u0111\u00edch (\u0111\u00edch)...S\u1ed1 ph\u1ea7n t\u1eed c\u1ea7n sao ch\u00e9p\r\n<\/pre>\n<h4>m\u00e3 m\u1eabu<\/h4>\n<pre class=\"sample_src\">\r\nstatic void arraycopySample() { String[] s1 = {&quot;apple&quot;, &quot;orange&quot;, &quot;grape&quot;}; String[] s2 = new String[5]; System.arraycopy(s1, 0, s2, 0, 3) ; s2[3] = &quot;chu\u1ed1i&quot;; s2[4] = &quot;anh \u0111\u00e0o&quot;; System.out.println(s1[0] + &quot; &quot; + s1[1] + &quot; &quot; + s1[2]); System.out .println(s2[0] + &quot; &quot; + s2[1] + &quot; &quot; + s2[2] + &quot; &quot; + s2[3] + &quot; &quot; + s2[4]); }\r\n<\/pre>\n<p>K\u1ebft qu\u1ea3 \u0111\u1ea7u ra:<\/p>\n<pre class=\"console\">\r\nT\u00e1o Cam Nho T\u00e1o Cam Nho Chu\u1ed1i Anh \u0111\u00e0o\r\n<\/pre>\n<p>Vi\u1ec7c s\u1eed d\u1ee5ng arraycopy khi n\u1ed1i c\u00e1c m\u1ea3ng c\u0169ng r\u1ea5t thu\u1eadn ti\u1ec7n.<\/p>\n<h4>m\u00e3 m\u1eabu<\/h4>\n<pre class=\"sample_src\">\r\nstatic void joinArraySample() { String[] s1 = {&quot;apple&quot;, &quot;qu\u00fdt&quot;, &quot;nho&quot;}; Chu\u1ed7i[] s2 = {&quot;chu\u1ed1i&quot;, &quot;anh \u0111\u00e0o&quot;, &quot;\u0111\u00e0o&quot;}; int rLen = s1.length + s2.length;String[] rStr = new String[rLen]; \/\/Kh\u1edfi t\u1ea1o m\u1ea3ng theo \u0111\u1ed9 d\u00e0i c\u1ee7a c\u1ea3 s1 v\u00e0 s2 System.arraycopy(s1, 0, rStr, 0, s1.length); System .arraycopy( s2, 0, rStr, s1.length, s2.length); \/\/ V\u1ea5n \u0111\u1ec1 l\u00e0 \u0111\u1eb7t v\u1ecb tr\u00ed b\u1eaft \u0111\u1ea7u c\u1ee7a m\u1ea3ng \u0111\u00edch sao ch\u00e9p System.out.println(rStr[0] + &quot; &quot; + rStr[1] + &quot; &quot; + rStr[2] + &quot; &quot; + rStr[3] + &quot; &quot; + rStr[4] + &quot; &quot; + rStr[5]); }\r\n<\/pre>\n<p>K\u1ebft qu\u1ea3 \u0111\u1ea7u ra:<\/p>\n<pre class=\"console\">\r\nT\u00e1o Qu\u00fdt Nho Chu\u1ed1i Anh \u0111\u00e0o \u0110\u00e0o\r\n<\/pre>\n<h2>T\u1ea1o m\u1ea3ng \u0111a chi\u1ec1u<\/h2>\n<p>B\u1ea1n c\u00f3 th\u1ec3 t\u1ea1o m\u1ea3ng nhi\u1ec1u chi\u1ec1u b\u1eb1ng c\u00e1ch t\u1ea1o m\u1ea3ng trong m\u1ea3ng. \u0110i\u1ec1u n\u00e0y r\u1ea5t h\u1eefu \u00edch khi l\u01b0u tr\u1eef d\u1eef li\u1ec7u b\u1ea3ng.<\/p>\n<h4>m\u00e3 m\u1eabu<\/h4>\n<pre class=\"sample_src\">\r\nstatic void twoDArraySample() { int[] a1 = {38, 84, 98}; int[] a2 = {32, 11, 56}; int[] a3 = {82, 77, 8}; int[][] twoDArray = {a1, a2, a3};for (int[] a : twoDArray) { for (int point : a) { System.out.print(score + &quot; &quot;); } System.out.println(&quot;&quot;) ; } }\r\n<\/pre>\n<p>K\u1ebft qu\u1ea3 \u0111\u1ea7u ra:<\/p>\n<pre class=\"console\">\r\n38 84 98 \r\n32 11 56 \r\n82 77 8 \r\n<\/pre>","protected":false},"excerpt":{"rendered":"<p>Kh\u1edfi t\u1ea1o m\u1ed9t m\u1ea3ng c\u00f9ng l\u00fac v\u1edbi vi\u1ec7c khai b\u00e1o B\u1ea1n c\u00f3 th\u1ec3 kh\u1edfi t\u1ea1o m\u1ed9t m\u1ea3ng c\u00f9ng l\u00fac v\u1edbi vi\u1ec7c khai b\u00e1o b\u1eb1ng c\u00e1ch vi\u1ebft nh\u01b0 sau. M\u00e3 m\u1eabu sta [\u2026]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"swell_btn_cv_data":""},"categories":[19],"tags":[],"_links":{"self":[{"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/posts\/4681"}],"collection":[{"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/comments?post=4681"}],"version-history":[{"count":6,"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/posts\/4681\/revisions"}],"predecessor-version":[{"id":4688,"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/posts\/4681\/revisions\/4688"}],"wp:attachment":[{"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/media?parent=4681"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/categories?post=4681"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chat-messenger.com\/vi\/wp-json\/wp\/v2\/tags?post=4681"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}