{"id":238,"date":"2026-07-15T08:53:55","date_gmt":"2026-07-15T00:53:55","guid":{"rendered":"http:\/\/ssjava.xyz\/?p=238"},"modified":"2026-07-16T10:52:13","modified_gmt":"2026-07-16T02:52:13","slug":"06-%e6%95%b0%e7%bb%84%e5%9f%ba%e7%a1%80%ef%bc%9a%e4%b8%80%e7%bb%b4%e6%95%b0%e7%bb%84%e3%80%81%e9%81%8d%e5%8e%86%e4%b8%8e%e5%b8%b8%e8%a7%81%e6%93%8d%e4%bd%9c","status":"publish","type":"post","link":"https:\/\/ssjava.xyz\/index.php\/2026\/07\/15\/06-%e6%95%b0%e7%bb%84%e5%9f%ba%e7%a1%80%ef%bc%9a%e4%b8%80%e7%bb%b4%e6%95%b0%e7%bb%84%e3%80%81%e9%81%8d%e5%8e%86%e4%b8%8e%e5%b8%b8%e8%a7%81%e6%93%8d%e4%bd%9c\/","title":{"rendered":"06. \u6570\u7ec4\u57fa\u7840\uff1a\u4e00\u7ef4\u6570\u7ec4\u3001\u904d\u5386\u4e0e\u5e38\u89c1\u64cd\u4f5c"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">\u5f00\u7bc7\u5f15\u5b50\u2014\u2014\u4e3a\u4ec0\u4e48\u9700\u8981\u6570\u7ec4\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u60f3\u8c61\u4e00\u4e0b\uff1a\u4f60\u8981\u5b58\u73ed\u4e0a 50 \u4e2a\u4eba\u7684\u6210\u7ee9\u3002\u6ca1\u6709\u6570\u7ec4\u7684\u8bdd\u2014\u2014<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int score1 = 85;\nint score2 = 92;\nint score3 = 67;\n\/\/ ... \u5199 50 \u884c\uff1f\nint score50 = 78;<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u800c\u60f3\u6c42\u4e2a\u5e73\u5747\u5206\uff1f\u624b\u5199 <code>score1 + score2 + ... + score50<\/code>\uff1f\u5199\u5230\u7b2c\u56db\u5341\u4e2a\u4f60\u5c31\u6000\u7591\u4eba\u751f\u4e86\u3002\u8fd9\u5c31\u662f\u6570\u7ec4\u5b58\u5728\u7684\u7406\u7531\u2014\u2014\u628a\u540c\u7c7b\u578b\u6570\u636e\u7ec4\u7ec7\u8d77\u6765\uff0c\u7528\u4e0b\u6807\u7edf\u4e00\u8bbf\u95ee\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e00\u3001\u4e00\u7ef4\u6570\u7ec4\u7684\u5b9a\u4e49<\/h2>\n\n\n<h3 class=\"wp-block-heading\">1.1 \u58f0\u660e\u548c\u521d\u59cb\u5316<\/h3>\n\n\n<p class=\"wp-block-paragraph\">Java \u91cc\u6570\u7ec4\u662f\u4e00\u4e2a<strong>\u5f15\u7528\u7c7b\u578b<\/strong>\uff0c\u6709\u56fa\u5b9a\u7684\u957f\u5ea6\uff0c\u4e00\u65e6\u521b\u5efa\u5c31\u4e0d\u80fd\u6539\u53d8\u3002\u8fd9\u662f\u5b83\u548c\u96c6\u5408\u7c7b\u7684\u6700\u5927\u533a\u522b\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u65b9\u5f0f\u4e00\uff1a\u58f0\u660e + \u5206\u914d\u7a7a\u95f4\nint&#91;] scores = new int&#91;5];\n\/\/ scores&#91;0]~scores&#91;4] \u9ed8\u8ba4\u90fd\u662f 0\n\n\/\/ \u65b9\u5f0f\u4e8c\uff1a\u58f0\u660e + \u76f4\u63a5\u8d4b\u503c\nint&#91;] scores2 = {85, 92, 67, 78, 90};\n\n\/\/ \u65b9\u5f0f\u4e09\uff1a\u5148\u58f0\u660e\uff0c\u518d new\nint&#91;] scores3;\nscores3 = new int&#91;]{85, 92, 67, 78, 90};  \/\/ \u6ce8\u610f\u8fd9\u91cc\u4e0d\u80fd\u7701\u7565 new int&#91;]\n\n\/\/ \u4e0d\u63a8\u8350\u7684\u5199\u6cd5\uff08c\u8bed\u8a00\u98ce\u683c\uff0cJava\u4e5f\u652f\u6301\u4f46\u522b\u8fd9\u4e48\u5199\uff09\nint scores4&#91;] = new int&#91;5];<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u4e09\u79cd\u58f0\u660e\u65b9\u5f0f\u7684\u533a\u522b\uff1a<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>\u65b9\u5f0f<\/th><th>\u4f7f\u7528\u573a\u666f<\/th><\/tr><\/thead><tbody><tr><td><code>new int[5]<\/code><\/td><td>\u5148\u5360\u4f4d\uff0c\u540e\u9762\u518d\u9010\u4e2a\u8d4b\u503c<\/td><\/tr><tr><td><code>{85, 92, ...}<\/code><\/td><td>\u521b\u5efa\u65f6\u5c31\u786e\u5b9a\u6240\u6709\u503c<\/td><\/tr><tr><td><code>new int[]{85, 92, ...}<\/code><\/td><td>\u53d8\u91cf\u58f0\u660e\u548c\u8d4b\u503c\u5206\u4e24\u884c\uff0c\u6216\u8005\u9700\u8981\u4f20\u53c2<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u6570\u7ec4\u7684\u957f\u5ea6\u7684\u83b7\u53d6\u7528 <code>\u6570\u7ec4\u540d.length<\/code>\uff0c\u6ce8\u610f<strong>\u4e0d\u662f\u65b9\u6cd5<\/strong>\uff0c\u662f\u5c5e\u6027\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = {10, 20, 30, 40, 50};\nSystem.out.println(arr.length);  \/\/ 5<\/code><\/pre>\n\n\n<h3 class=\"wp-block-heading\">1.2 \u9ed8\u8ba4\u503c<\/h3>\n\n\n<p class=\"wp-block-paragraph\">\u53ea <code>new<\/code> \u4e86\u7a7a\u95f4\u4f46\u4e0d\u8d4b\u503c\u7684\u8bdd\uff0c\u5143\u7d20\u6709\u9ed8\u8ba4\u503c\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>\u7c7b\u578b<\/th><th>\u9ed8\u8ba4\u503c<\/th><\/tr><\/thead><tbody><tr><td>byte\/short\/int\/long<\/td><td>0<\/td><\/tr><tr><td>float\/double<\/td><td>0.0<\/td><\/tr><tr><td>char<\/td><td>&#8216;u0000&#8217;\uff08\u7a7a\u5b57\u7b26\uff09<\/td><\/tr><tr><td>boolean<\/td><td>false<\/td><\/tr><tr><td>\u5f15\u7528\u7c7b\u578b\uff08String\u3001\u5bf9\u8c61\u7b49\uff09<\/td><td>null<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u4e2a\u9ed8\u8ba4\u503c\u673a\u5236\u633a\u65b9\u4fbf\u7684\uff0c\u6bd4\u5982\u4f60\u7edf\u8ba1\u67d0\u4e2a\u8303\u56f4\u5185\u6570\u5b57\u51fa\u73b0\u7684\u6b21\u6570\uff0c\u6574\u578b\u6570\u7ec4\u4e00\u521b\u5efa\u5168\u662f 0\uff0c\u53ef\u4ee5\u76f4\u63a5\u81ea\u589e\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e8c\u3001\u6570\u7ec4\u7684\u904d\u5386<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u904d\u5386\u5c31\u662f&#8221;\u628a\u6570\u7ec4\u6bcf\u4e2a\u5143\u7d20\u8fc7\u4e00\u904d&#8221;\u3002Java \u63d0\u4f9b\u4e86\u4e24\u79cd\u65b9\u5f0f\uff1a<\/p>\n\n\n<h3 class=\"wp-block-heading\">2.1 for \u5faa\u73af\uff08\u4e0b\u6807\u904d\u5386\uff09<\/h3>\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] scores = {85, 92, 67, 78, 90};\nfor (int i = 0; i &lt; scores.length; i++) {\n    System.out.println(\"\u7b2c\" + (i + 1) + \"\u4e2a\u6210\u7ee9\uff1a\" + scores&#91;i]);\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u662f\u6700\u7ecf\u5178\u7684\u904d\u5386\u65b9\u5f0f\u3002\u4f18\u70b9\uff1a\u80fd\u62ff\u5230\u4e0b\u6807\uff0c\u65b9\u4fbf\u4fee\u6539\u5143\u7d20\u3002\u7f3a\u70b9\uff1a\u5199\u6cd5\u5570\u55e6\u4e86\u70b9\u3002<\/p>\n\n\n<h3 class=\"wp-block-heading\">2.2 \u589e\u5f3a for \u5faa\u73af\uff08foreach\uff09<\/h3>\n\n\n<pre class=\"wp-block-code\"><code>for (int score : scores) {\n    System.out.println(score);\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">Java 5 \u5f15\u5165\u7684\u8bed\u6cd5\u7cd6\u3002\u4f18\u70b9\uff1a\u4ee3\u7801\u7b80\u6d01\u3001\u4e0d\u4f1a\u6709\u4e0b\u6807\u8d8a\u754c\u95ee\u9898\u3002\u7f3a\u70b9\uff1a\u62ff\u4e0d\u5230\u4e0b\u6807\uff0c\u4e5f\u4e0d\u80fd\u4fee\u6539\u6570\u7ec4\u5143\u7d20\uff08\u4fee\u6539\u7684\u662f\u4e34\u65f6\u53d8\u91cf\uff09\u3002<\/p>\n\n\n<h3 class=\"wp-block-heading\">2.3 \u7528 Arrays.toString() \u5feb\u901f\u6253\u5370<\/h3>\n\n\n<p class=\"wp-block-paragraph\">\u8c03\u8bd5\u65f6\u6700\u5e38\u7528\u7684\u65b9\u5f0f\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import java.util.Arrays;\n\nint&#91;] scores = {85, 92, 67, 78, 90};\nSystem.out.println(Arrays.toString(scores));\n\/\/ \u8f93\u51fa\uff1a&#91;85, 92, 67, 78, 90]<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u5343\u4e07\u522b\u76f4\u63a5\u6253\u5370\u6570\u7ec4\u53d8\u91cf\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>System.out.println(scores);\n\/\/ \u8f93\u51fa\uff1a&#91;I@1b6d3586  \u2190 \u54c8\u5e0c\u5730\u5740\uff0c\u4e0d\u662f\u5185\u5bb9\uff01<\/code><\/pre>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>\ud83d\udca1 \u6211\u5728\u5927\u5b66\u4e0a Java \u8bfe\u65f6\uff0c\u7b2c\u4e00\u6b21\u6253\u5370\u6570\u7ec4\u76f4\u63a5\u4f20\u4e86\u53d8\u91cf\u540d\uff0c\u8f93\u51fa\u4e00\u4e32\u770b\u4e0d\u61c2\u7684\u4e1c\u897f\uff0c\u4ee5\u4e3a\u7a0b\u5e8f\u51fa bug \u4e86\u2026\u2026\u540e\u6765\u540c\u5b66\u544a\u8bc9\u6211\u8981\u7528 Arrays.toString()\u3002\u5982\u679c\u4f60\u4e5f\u8e29\u8fc7\u8fd9\u4e2a\u5751\uff0c\u4f60\u4e0d\u662f\u4e00\u4e2a\u4eba\u3002<\/strong><\/p>\n<\/blockquote>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e09\u3001\u6570\u7ec4\u7684\u5e38\u89c1\u64cd\u4f5c<\/h2>\n\n\n\n<h2 class=\"wp-block-heading\">3.1 \u6c42\u6700\u5927\u503c\u548c\u6700\u5c0f\u503c<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = {5, 3, 9, 1, 7, 6};\n\n\/\/ \u6c42\u6700\u5927\u503c\nint max = arr&#91;0];\nfor (int i = 1; i &lt; arr.length; i++) {\n    if (arr&#91;i] &gt; max) {\n        max = arr&#91;i];\n    }\n}\nSystem.out.println(\"\u6700\u5927\u503c\uff1a\" + max);  \/\/ 9\n\n\/\/ \u6c42\u6700\u5c0f\u503c\u540c\u7406\uff0c\u628a &gt; \u6362\u6210 &lt;\nint min = arr&#91;0];\nfor (int i = 1; i &lt; arr.length; i++) {\n    if (arr&#91;i] &lt; min) {\n        min = arr&#91;i];\n    }\n}\nSystem.out.println(\"\u6700\u5c0f\u503c\uff1a\" + min);  \/\/ 1<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u6ce8\u610f\uff1a<\/strong>\u521d\u59cb\u503c\u8bbe\u4e3a <code>arr[0]<\/code>\uff0c\u4e0d\u8981\u8bbe\u6210 <code>0<\/code> \u6216 <code>Integer.MAX_VALUE<\/code>\u2014\u2014\u4e07\u4e00\u6570\u7ec4\u91cc\u5168\u662f\u8d1f\u6570\uff0c<code>max = 0<\/code> \u5c31\u9519\u4e86\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.2 \u6c42\u548c\u4e0e\u5e73\u5747\u503c<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] scores = {85, 92, 67, 78, 90};\nint sum = 0;\n\nfor (int score : scores) {\n    sum += score;\n}\n\ndouble avg = (double) sum \/ scores.length;\nSystem.out.println(\"\u603b\u5206\uff1a\" + sum);      \/\/ 412\nSystem.out.println(\"\u5e73\u5747\u5206\uff1a\" + avg);    \/\/ 82.4<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u91cc\u8981\u628a <code>sum<\/code> \u5f3a\u8f6c\u6210 <code>double<\/code>\uff0c\u5426\u5219\u4e24\u4e2a int \u76f8\u9664\u7ed3\u679c\u4f1a\u88ab\u622a\u65ad\u4e3a\u6574\u6570\u3002<br>\u6bd4\u5982 412 \/ 5 = 82\uff08\u800c\u4e0d\u662f 82.4\uff09\uff0c\u8fd9\u5751\u5f53\u5e74\u6211\u4e5f\u8e29\u8fc7\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.3 \u67e5\u627e\u5143\u7d20<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = {5, 3, 9, 1, 7, 6};\nint target = 7;\nint index = -1;  \/\/ -1 \u8868\u793a\u672a\u627e\u5230\n\nfor (int i = 0; i &lt; arr.length; i++) {\n    if (arr&#91;i] == target) {\n        index = i;\n        break;  \/\/ \u627e\u5230\u4e86\u5c31\u9000\u51fa\uff0c\u522b\u7ee7\u7eed\u767d\u627e\n    }\n}\n\nif (index != -1) {\n    System.out.println(target + \" \u5728\u4f4d\u7f6e \" + index);\n} else {\n    System.out.println(target + \" \u4e0d\u5728\u6570\u7ec4\u4e2d\");\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u662f<strong>\u7ebf\u6027\u67e5\u627e<\/strong>\uff0c\u6700\u6734\u7d20\u7684\u67e5\u627e\u65b9\u5f0f\u3002\u5bf9\u4e8e\u65e0\u5e8f\u6570\u7ec4\u8fd9\u662f\u552f\u4e00\u7684\u9009\u62e9\uff1b\u5bf9\u4e8e\u6709\u5e8f\u6570\u7ec4\uff0c\u540e\u9762\u4f1a\u5b66\u5230\u4e8c\u5206\u67e5\u627e\uff0c\u6548\u7387\u66f4\u9ad8\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.4 \u6570\u7ec4\u5143\u7d20\u53cd\u8f6c<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = {1, 2, 3, 4, 5};\n\nfor (int i = 0, j = arr.length - 1; i &lt; j; i++, j--) {\n    \/\/ \u4ea4\u6362 arr&#91;i] \u548c arr&#91;j]\n    int temp = arr&#91;i];\n    arr&#91;i] = arr&#91;j];\n    arr&#91;j] = temp;\n}\n\nSystem.out.println(Arrays.toString(arr));  \/\/ &#91;5, 4, 3, 2, 1]<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u5173\u952e\u70b9\uff1a<\/strong>\u53ea\u904d\u5386\u4e00\u534a\uff0c\u7528\u4e24\u4e2a\u6307\u9488\u4ece\u4e24\u7aef\u5411\u4e2d\u95f4\u8d70\u3002<code>i &lt; j<\/code> \u4fdd\u8bc1\u4e86\u5947\u6570\u957f\u5ea6\u65f6\u4e2d\u95f4\u5143\u7d20\u4e0d\u52a8\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.5 \u6570\u7ec4\u62f7\u8d1d<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] src = {1, 2, 3, 4, 5};\n\n\/\/ \u65b9\u5f0f\u4e00\uff1afor \u5faa\u73af\u624b\u52a8\u62f7\u8d1d\nint&#91;] dest1 = new int&#91;src.length];\nfor (int i = 0; i &lt; src.length; i++) {\n    dest1&#91;i] = src&#91;i];\n}\n\n\/\/ \u65b9\u5f0f\u4e8c\uff1aSystem.arraycopy()\uff08\u539f\u751f\u65b9\u6cd5\uff0c\u6548\u7387\u6700\u9ad8\uff09\nint&#91;] dest2 = new int&#91;src.length];\nSystem.arraycopy(src, 0, dest2, 0, src.length);\n\n\/\/ \u65b9\u5f0f\u4e09\uff1aArrays.copyOf()\uff08\u6700\u65b9\u4fbf\uff09\nint&#91;] dest3 = Arrays.copyOf(src, src.length);\n\n\/\/ \u65b9\u5f0f\u56db\uff1aclone()\nint&#91;] dest4 = src.clone();<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u51e0\u4e2a <code>copyOf<\/code> \u7684\u5999\u7528\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/ \u622a\u53d6\u524d3\u4e2a\u5143\u7d20\nint&#91;] part1 = Arrays.copyOf(src, 3);       \/\/ &#91;1, 2, 3]\n\n\/\/ \u6269\u5c55\u957f\u5ea6\uff08\u591a\u4f59\u4f4d\u7f6e\u88650\uff09\nint&#91;] expanded = Arrays.copyOf(src, 7);   \/\/ &#91;1, 2, 3, 4, 5, 0, 0]\n\n\/\/ \u590d\u5236\u6307\u5b9a\u8303\u56f4\uff08from \u5305\u542b\uff0cto \u4e0d\u5305\u542b\uff09\nint&#91;] range = Arrays.copyOfRange(src, 1, 4);  \/\/ &#91;2, 3, 4]<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">3.6 \u5192\u6ce1\u6392\u5e8f\uff08\u5165\u95e8\u7ea7\u6392\u5e8f\uff09<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6392\u5e8f\u7b97\u6cd5\u662f\u9762\u8bd5\u5e38\u5ba2\uff0c\u4f46\u4f5c\u4e3a\u521d\u5b66\u8005\uff0c\u5148\u638c\u63e1<strong>\u5192\u6ce1\u6392\u5e8f<\/strong>\u5c31\u591f\u4e86\u2014\u2014\u5b83\u6700\u76f4\u89c2\uff0c\u4e5f\u6700\u5bb9\u6613\u7406\u89e3\u6392\u5e8f\u7684&#8221;\u6bd4\u8f83-\u4ea4\u6362&#8221;\u601d\u60f3\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = {5, 3, 9, 1, 7};\n\/\/ \u5347\u5e8f\u6392\u5217\n\nfor (int i = 0; i &lt; arr.length - 1; i++) {\n    for (int j = 0; j &lt; arr.length - 1 - i; j++) {\n        if (arr&#91;j] &gt; arr&#91;j + 1]) {\n            int temp = arr&#91;j];\n            arr&#91;j] = arr&#91;j + 1];\n            arr&#91;j + 1] = temp;\n        }\n    }\n}\n\nSystem.out.println(Arrays.toString(arr));  \/\/ &#91;1, 3, 5, 7, 9]<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u539f\u7406\u56fe\u89e3\uff1a<\/strong>\u6bcf\u4e00\u8f6e\u628a\u5f53\u524d\u672a\u6392\u5e8f\u90e8\u5206\u7684\u6700\u5927\u503c&#8221;\u5192\u6ce1&#8221;\u5230\u6700\u540e\u3002<code>arr.length - 1 - i<\/code> \u8868\u793a\u6bcf\u8f6e\u6bd4\u8f83\u6b21\u6570\u9012\u51cf\u2014\u2014\u6700\u540e\u9762\u7684\u5143\u7d20\u5df2\u7ecf\u6392\u597d\u4e86\uff0c\u4e0d\u9700\u8981\u518d\u6bd4\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u56db\u3001\u5e38\u89c1\u9677\u9631\u548c\u6ce8\u610f\u4e8b\u9879<\/h2>\n\n\n\n<h2 class=\"wp-block-heading\">4.1 \u6570\u7ec4\u4e0b\u6807\u8d8a\u754c<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6570\u7ec4\u4e0b\u6807\u4ece 0 \u5f00\u59cb\uff0c\u5230 <code>length - 1<\/code> \u7ed3\u675f\u3002\u8bbf\u95ee <code>arr[arr.length]<\/code> \u4f1a\u629b\u51fa <code>ArrayIndexOutOfBoundsException<\/code>\u2014\u2014\u8fd9\u662f\u521d\u5b66\u8005\u6700\u5e38\u89c1\u7684\u5f02\u5e38\u4e4b\u4e00\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = {1, 2, 3};\nSystem.out.println(arr&#91;3]);  \/\/ \u274c \u8fd0\u884c\u62a5\u9519\uff01\u4e0b\u6807\u6700\u5927\u662f 2<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">4.2 \u7a7a\u6307\u9488\u8bbf\u95ee<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = null;\nSystem.out.println(arr.length);  \/\/ \u274c NullPointerException\n\/\/ \u6570\u7ec4\u662f\u5f15\u7528\u7c7b\u578b\uff0c\u4e0d new \u5c31\u662f null\uff0c\u8c03 length \u4f1a\u5d29<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">4.3 foreach \u91cc\u4e0d\u80fd\u4fee\u6539\u539f\u6570\u7ec4<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>int&#91;] arr = {1, 2, 3};\nfor (int x : arr) {\n    x = 100;  \/\/ \u274c \u8fd9\u53ea\u662f\u6539\u4e86\u4e00\u4e2a\u4e34\u65f6\u53d8\u91cf\uff0c\u539f\u6570\u7ec4\u6ca1\u53d8\n}\nSystem.out.println(Arrays.toString(arr));  \/\/ \u8fd8\u662f &#91;1, 2, 3]<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u60f3\u4fee\u6539\u6570\u7ec4\u5143\u7d20\uff0c\u5fc5\u987b\u7528\u4e0b\u6807 for \u5faa\u73af\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e94\u3001\u7efc\u5408\u793a\u4f8b\uff1a\u5b66\u751f\u6210\u7ee9\u7ba1\u7406\u7cfb\u7edf\uff08\u7b80\u6613\u7248\uff09<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u628a\u4eca\u5929\u5b66\u7684\u64cd\u4f5c\u4e32\u8d77\u6765\uff0c\u5199\u4e00\u4e2a\u5c0f\u7a0b\u5e8f\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import java.util.Arrays;\n\npublic class ScoreManager {\n    public static void main(String&#91;] args) {\n        \/\/ 5 \u4e2a\u5b66\u751f\u7684\u6210\u7ee9\n        int&#91;] scores = {76, 88, 62, 95, 81};\n        \n        \/\/ 1. \u6253\u5370\u539f\u59cb\u6210\u7ee9\n        System.out.println(\"\u539f\u59cb\u6210\u7ee9\uff1a\" + Arrays.toString(scores));\n        \n        \/\/ 2. \u7edf\u8ba1\n        int sum = 0;\n        int max = scores&#91;0];\n        int min = scores&#91;0];\n        for (int score : scores) {\n            sum += score;\n            if (score &gt; max) max = score;\n            if (score &lt; min) min = score;\n        }\n        double avg = (double) sum \/ scores.length;\n        \n        System.out.println(\"\u603b\u5206\uff1a\" + sum);\n        System.out.println(\"\u5e73\u5747\u5206\uff1a\" + avg);\n        System.out.println(\"\u6700\u9ad8\u5206\uff1a\" + max);\n        System.out.println(\"\u6700\u4f4e\u5206\uff1a\" + min);\n        \n        \/\/ 3. \u67e5\u627e 95 \u5206\u7684\u4f4d\u7f6e\n        int target = 95;\n        int index = -1;\n        for (int i = 0; i &lt; scores.length; i++) {\n            if (scores&#91;i] == target) {\n                index = i;\n                break;\n            }\n        }\n        System.out.println(target + \" \u5206\u5728\u7b2c \" + (index + 1) + \" \u4f4d\");\n        \n        \/\/ 4. \u6309\u6210\u7ee9\u4ece\u4f4e\u5230\u9ad8\u6392\u5e8f\n        int&#91;] sorted = Arrays.copyOf(scores, scores.length);\n        Arrays.sort(sorted);  \/\/ \u76f4\u63a5\u7528\u5de5\u5177\u7c7b\u6392\u5e8f\n        System.out.println(\"\u6309\u6210\u7ee9\u6392\u5e8f\uff1a\" + Arrays.toString(sorted));\n        \n        \/\/ 5. \u627e\u51fa\u4e0d\u53ca\u683c\uff08\u4f4e\u4e8e 60 \u5206\uff09\u7684\u4eba\u6570\n        \/\/ \u8fd9\u91cc\u6ca1\u6709\u4e0d\u53ca\u683c\u7684\uff0c\u4f46\u65b9\u6cd5\u5b66\u4f1a\u4e86\n        int failCount = 0;\n        for (int score : scores) {\n            if (score &lt; 60) failCount++;\n        }\n        System.out.println(\"\u4e0d\u53ca\u683c\u4eba\u6570\uff1a\" + failCount);\n    }\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u8fd0\u884c\u7ed3\u679c\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u539f\u59cb\u6210\u7ee9\uff1a&#91;76, 88, 62, 95, 81]\n\u603b\u5206\uff1a402\n\u5e73\u5747\u5206\uff1a80.4\n\u6700\u9ad8\u5206\uff1a95\n\u6700\u4f4e\u5206\uff1a62\n95 \u5206\u5728\u7b2c 4 \u4f4d\n\u6309\u6210\u7ee9\u6392\u5e8f\uff1a&#91;62, 76, 81, 88, 95]\n\u4e0d\u53ca\u683c\u4eba\u6570\uff1a0<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">\u603b\u7ed3<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u6570\u7ec4<\/strong>\u662f\u957f\u5ea6\u56fa\u5b9a\u7684\u540c\u7c7b\u578b\u6570\u636e\u5bb9\u5668\uff0c\u4e0b\u6807\u4ece 0 \u5f00\u59cb\uff0c\u8bbf\u95ee\u8d8a\u754c\u4f1a\u629b\u5f02\u5e38<\/li>\n\n\n\n<li><strong>\u58f0\u660e\u65b9\u5f0f<\/strong>\u6709 <code>int[] arr = new int[n]<\/code>\u3001<code>{\u503c1, \u503c2}<\/code>\u3001<code>new int[]{\u503c1, \u503c2}<\/code> \u4e09\u79cd<\/li>\n\n\n\n<li><strong>\u904d\u5386<\/strong>\u7528 for \u4e0b\u6807\u5faa\u73af\uff08\u80fd\u4fee\u6539\u5143\u7d20\uff09\u6216 foreach\uff08\u53ea\u8bfb\uff09<\/li>\n\n\n\n<li><strong>\u5e38\u7528\u64cd\u4f5c<\/strong>\uff1a\u6c42\u548c\u3001\u6c42\u6700\u503c\u3001\u67e5\u627e\u3001\u53cd\u8f6c\u3001\u62f7\u8d1d\u3001\u6392\u5e8f<\/li>\n\n\n\n<li><strong>\u5de5\u5177\u7c7b<\/strong> <code>Arrays.toString()<\/code> \u548c <code>Arrays.sort()<\/code> \u8ba9\u65e5\u5e38\u64cd\u4f5c\u7b80\u6d01\u5f88\u591a<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0b\u4e00\u7bc7\u6211\u4eec\u804a<strong>\u591a\u7ef4\u6570\u7ec4<\/strong>\u548c <code>Arrays<\/code> \u5de5\u5177\u7c7b\u7684\u66f4\u591a\u7528\u6cd5\uff0c\u8fd8\u4f1a\u8bb2\u5230\u53ef\u53d8\u53c2\u6570\u2014\u2014\u5230\u65f6\u5019\u4f60\u4f1a\u53d1\u73b0\u5f88\u591a\u64cd\u4f5c\u6839\u672c\u4e0d\u9700\u8981\u624b\u5199\u5faa\u73af\u4e86\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5f00\u7bc7\u5f15\u5b50\u2014\u2014\u4e3a\u4ec0\u4e48\u9700\u8981\u6570\u7ec4\uff1f \u60f3\u8c61\u4e00\u4e0b\uff1a\u4f60\u8981\u5b58\u73ed\u4e0a 50 \u4e2a\u4eba\u7684\u6210\u7ee9\u3002\u6ca1\u6709\u6570\u7ec4\u7684\u8bdd\u2014\u2014 \u800c\u60f3\u6c42\u4e2a\u5e73\u5747\u5206\uff1f\u624b\u5199  [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[44],"tags":[],"class_list":["post-238","post","type-post","status-publish","format-standard","hentry","category-array-method"],"_links":{"self":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts\/238","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/comments?post=238"}],"version-history":[{"count":1,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts\/238\/revisions"}],"predecessor-version":[{"id":243,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/posts\/238\/revisions\/243"}],"wp:attachment":[{"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/media?parent=238"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/categories?post=238"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ssjava.xyz\/index.php\/wp-json\/wp\/v2\/tags?post=238"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}