{"id":31002,"date":"2023-08-04T05:58:44","date_gmt":"2024-03-08T16:51:10","guid":{"rendered":"https:\/\/www.silicloud.com\/zh\/blog\/%e3%80%90java%e3%80%91%e5%a6%82%e4%bd%95%e9%81%bf%e5%85%8djava-lang-nullpointerexception\/"},"modified":"2025-08-12T21:48:50","modified_gmt":"2025-08-12T13:48:50","slug":"%e3%80%90java%e3%80%91%e5%a6%82%e4%bd%95%e9%81%bf%e5%85%8djava-lang-nullpointerexception","status":"publish","type":"post","link":"https:\/\/www.silicloud.com\/zh\/blog\/%e3%80%90java%e3%80%91%e5%a6%82%e4%bd%95%e9%81%bf%e5%85%8djava-lang-nullpointerexception\/","title":{"rendered":"\u3010Java\u3011\u5982\u4f55\u907f\u514djava.lang.NullPointerException"},"content":{"rendered":"<p>#\u7f16\u7a0b\u5b66\u4e60\u65e5\u8bb0<br \/>\n2021\u5e741\u670823\u65e5<br \/>\n\u603b\u7ed3\u4e86\u5728\u7f16\u5199Java\u4ee3\u7801\u65f6\u7ecf\u5e38\u9047\u5230\u7684NullPointerExcption\u7684\u610f\u4e49\u4ee5\u53ca\u907f\u514d\u51fa\u73b0NullPointerExcption\u7684\u65b9\u6cd5\u3002<\/p>\n<pre class=\"post-pre\"><code>Request processing failed; nested exception is java.lang.NullPointerException\r\n<\/code><\/pre>\n<p>\u5f53\u53c2\u7167\u7c7b\u578b\u7684\u53d8\u91cf\u503c\u5b58\u50a8\u4e3anull\u65f6\uff0c\u5728\u8bd5\u56fe\u5f15\u7528\u5b83\u65f6\u4f1a\u53d1\u751f\u7684\u5f02\u5e38\u88ab\u79f0\u4e3aNullPointerException\u3002<\/p>\n<blockquote><p>\u7a7a\u6307\u9488\u5f02\u5e38\uff08NullPointerException\uff09\u662fJava\u7f16\u7a0b\u8bed\u8a00\u4e2d\u7684\u4e00\u79cd\u5f02\u5e38\u60c5\u51b5\u3002\u5f53\u5f15\u7528\u7c7b\u578b\u53d8\u91cf\u5c1d\u8bd5\u5f15\u7528\u4e00\u4e2a\u7a7a\u503c\uff08\u672a\u5b9a\u4e49\u7684\u503c\uff09\u65f6\uff0c\u5c31\u4f1a\u53d1\u751f\u7a7a\u6307\u9488\u5f02\u5e38\u3002\u7531\u4e8eNullPointerException\u662fjava.lang.RuntimeException\u7c7b\u7684\u5b50\u7c7b\uff0c\u56e0\u6b64\u5373\u4f7f\u4e0d\u7f16\u5199try-catch\u8bed\u53e5\u5757\u6765\u5904\u7406\u5f02\u5e38\uff0c\u4e5f\u4e0d\u4f1a\u53d1\u751f\u7f16\u8bd1\u9519\u8bef\u3002\uff08\u5f15\u7528\uff1ahttps:\/\/ja.wikipedia.org\/wiki\/NullPointerException\uff09<\/p><\/blockquote>\n<p>\u56e0\u6b64\uff0c\u5982\u679c\u662f\u4ee5\u4e0b\u7684\u4ee3\u7801\uff0c\u4f1a\u53d1\u751f\u7a7a\u6307\u9488\u5f02\u5e38\u3002<\/p>\n<pre class=\"post-pre\"><code><span class=\"kd\">class<\/span> <span class=\"nc\">Sample<\/span><span class=\"o\">{<\/span>\r\n    <span class=\"kd\">public<\/span> <span class=\"kd\">static<\/span> <span class=\"kt\">void<\/span> <span class=\"nf\">main<\/span><span class=\"o\">(<\/span><span class=\"nc\">String<\/span><span class=\"o\">[]<\/span> <span class=\"n\">args<\/span><span class=\"o\">)<\/span> <span class=\"o\">{<\/span>\r\n        <span class=\"nc\">Integer<\/span> <span class=\"n\">i<\/span> <span class=\"o\">=<\/span> <span class=\"kc\">null<\/span><span class=\"o\">;<\/span>\r\n        <span class=\"n\">i<\/span><span class=\"o\">.<\/span><span class=\"na\">toString<\/span><span class=\"o\">();<\/span>\r\n    <span class=\"o\">}<\/span>\r\n<span class=\"o\">}<\/span>\r\n<\/code><\/pre>\n<p>\u907f\u514d\u7a7a\u6307\u9488\u5f02\u5e38\u7684\u65b9\u6cd5\u662f\u57fa\u672c\u4e0a\u53ea\u9700\u8981\u5224\u65ad\u5f15\u7528\u7c7b\u578b\u53d8\u91cf\u662f\u5426\u4e3anull\u3002\u901a\u8fc7\u5c06\u4ee3\u7801\u4fee\u6539\u4e3a\u5982\u679c\u5f15\u7528\u7c7b\u578b\u53d8\u91cf\u4e3anull\uff0c\u5219\u4e0d\u6267\u884c\u4efb\u4f55\u5904\u7406\uff0c\u5c31\u80fd\u591f\u6d88\u9664\u7a7a\u6307\u9488\u5f02\u5e38\u3002<\/p>\n<pre class=\"post-pre\"><code><span class=\"kd\">class<\/span> <span class=\"nc\">Sample<\/span><span class=\"o\">{<\/span>\r\n    <span class=\"kd\">public<\/span> <span class=\"kd\">static<\/span> <span class=\"kt\">void<\/span> <span class=\"nf\">main<\/span><span class=\"o\">(<\/span><span class=\"nc\">String<\/span><span class=\"o\">[]<\/span> <span class=\"n\">args<\/span><span class=\"o\">)<\/span> <span class=\"o\">{<\/span>\r\n        <span class=\"nc\">Integer<\/span> <span class=\"n\">i<\/span> <span class=\"o\">=<\/span> <span class=\"kc\">null<\/span><span class=\"o\">;<\/span>\r\n        <span class=\"c1\">\/\/ i \u304cnull\u306e\u5834\u5408\u3001\u51e6\u7406\u3092\u3057\u306a\u3044<\/span>\r\n        <span class=\"k\">if<\/span><span class=\"o\">(<\/span><span class=\"n\">i<\/span> <span class=\"o\">==<\/span> <span class=\"kc\">null<\/span><span class=\"o\">)<\/span> <span class=\"o\">{<\/span>\r\n            <span class=\"k\">return<\/span><span class=\"o\">;<\/span>\r\n        <span class=\"o\">}<\/span>\r\n        <span class=\"n\">i<\/span><span class=\"o\">.<\/span><span class=\"na\">toString<\/span><span class=\"o\">();<\/span>\r\n    <span class=\"o\">}<\/span>\r\n<span class=\"o\">}<\/span>\r\n<\/code><\/pre>\n<p>\u7136\u800c\uff0c\u968f\u7740\u4ee3\u7801\u91cf\u7684\u589e\u52a0\uff0c\u5224\u65ad\u53d8\u5f97\u66f4\u52a0\u56f0\u96be\uff0c\u56e0\u6b64\u9700\u8981\u63d0\u4f9b\u89e3\u51b3\u65b9\u6cd5\u3002<\/p>\n<ol>\n<li style=\"list-style-type: none;\">\n<ol>\u7528\u975e\u7a7a\u503c\u521d\u59cb\u5316\u53d8\u91cf<\/ol>\n<\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<ol>\n<li style=\"list-style-type: none;\">\n<ol>\u6570\u7ec4\u4ee5\u7a7a\u503c\u521d\u59cb\u5316<\/ol>\n<\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<ol>\u8fd4\u56de\u503c\u4e0d\u4e3anull<\/ol>\n<p>\u6211\u89c9\u5f97\u53ea\u8981\u6ce8\u610f\u5230\u8fd9\u4e09\u70b9\uff0c\u5c31\u80fd\u51cf\u5c11NullPointerException\u7684\u53d1\u751f\u3002<\/p>\n<p>\u3010Java\u3011java.lang.NullPointerException \u53ef\u53c2\u8003\u6587\u732e<\/p>\n","protected":false},"excerpt":{"rendered":"<p>#\u7f16\u7a0b\u5b66\u4e60\u65e5\u8bb0 2021\u5e741\u670823\u65e5 \u603b\u7ed3\u4e86\u5728\u7f16\u5199Java\u4ee3\u7801\u65f6\u7ecf\u5e38\u9047\u5230\u7684NullPointerExcptio [&hellip;]<\/p>\n","protected":false},"author":9,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[227],"class_list":["post-31002","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-227"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v21.5 (Yoast SEO v21.5) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>\u3010Java\u3011\u5982\u4f55\u907f\u514djava.lang.NullPointerException - Blog - Silicon Cloud<\/title>\n<meta name=\"description\" content=\"\u5173\u4e8e\u3010Java\u3011\u5982\u4f55\u907f\u514djava.lang.NullPointerException\u7684\u6280\u672f\u6587\u7ae0\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" 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