{"id":580,"date":"2015-04-26T19:26:02","date_gmt":"2015-04-26T11:26:02","guid":{"rendered":"https:\/\/ai.zhousir.top\/?p=580"},"modified":"2026-08-18T12:09:31","modified_gmt":"2026-08-18T04:09:31","slug":"java%e7%9a%84io%e6%80%a7%e8%83%bd%e8%b0%83%e6%95%b4","status":"publish","type":"post","link":"https:\/\/ai.zhousir.top\/?p=580","title":{"rendered":"Java\u7684IO\u6027\u80fd\u8c03\u6574"},"content":{"rendered":"<section id=\"wenyan\" style=\"font-family: system-ui, 'Apple Color Emoji', 'Segoe UI', 'Segoe UI Symbol', 'Noto Sans', Roboto, sans-serif; line-height: 1.75; font-size: 16px; color: #000000; caret-color: #000000;\" data-provider=\"WenYan\">\n<p style=\"margin: 1em 0px;\">\u672c\u6587\u591a\u6570\u6280\u5de7\u56f4\u7ed5\u78c1\u76d8\u6587\u4ef6 I\/O\uff0c\u4f46\u540c\u6837\u9002\u5408\u7f51\u7edc I\/O \u548c\u7a97\u53e3\u8f93\u51fa\u3002\u5148\u770b\u5e95\u5c42\u8bfb\u5199\uff0c\u518d\u8c08\u538b\u7f29\u3001\u683c\u5f0f\u5316\u548c\u4e32\u884c\u5316\u7b49\u9ad8\u7ea7\u95ee\u9898\uff1b\u4e0d\u6d89\u53ca\u641c\u7d22\u7b97\u6cd5\u3001\u6570\u636e\u7ed3\u6784\uff0c\u4e5f\u4e0d\u8c08\u7cfb\u7edf\u7ea7\u6587\u4ef6\u9ad8\u901f\u7f13\u51b2\u3002<\/p>\n<p><!--more--><\/p>\n<p style=\"margin: 1em 0px;\">Java \u5bf9\u78c1\u76d8\u6587\u4ef6\u6709\u4e24\u5957\u7ed3\u6784\uff1a\u57fa\u4e8e<strong style=\"color: #4870ac;\">\u5b57\u8282\u6d41<\/strong>\u7684\uff0c\u4ee5\u53ca\u57fa\u4e8e<strong style=\"color: #4870ac;\">\u5b57\u7b26\u5e8f\u5217<\/strong>\u7684\u3002Java \u91cc\u4e00\u4e2a\u5b57\u7b26\u5360\u4e24\u4e2a\u5b57\u8282\uff0c\u4e0d\u50cf C \u90a3\u6837\u4e00\u4e2a\u5b57\u8282\u5c31\u662f\u4e00\u4e2a\u5b57\u7b26\uff0c\u6240\u4ee5\u4ece\u6587\u4ef6\u8bfb\u5b57\u7b26\u65f6\u5fc5\u987b\u8f6c\u6362\u3002\u8fd9\u4e2a\u5dee\u522b\u5728\u4e0b\u9762\u7684\u8ba1\u65f6\u4f8b\u5b50\u91cc\u5f88\u660e\u663e\u3002<\/p>\n<h2 style=\"padding: 1px 12.5px; color: #ffffff; margin: 1.2em 0px 1em; border-radius: 4px; display: inline-block; background-color: #4870ac; font-size: 1.3em;\">\u4e00\u3001\u4f4e\u7ea7\u4e0e\u9ad8\u7ea7 I\/O \u6e05\u5355<\/h2>\n<p style=\"margin: 1em 0px;\">\u4f4e\u7ea7 I\/O \u76f8\u5173\u95ee\u9898\uff1a\u7f13\u51b2\u3001\u8bfb\u5199\u6587\u672c\u6587\u4ef6\u3001\u683c\u5f0f\u5316\u7684\u4ee3\u4ef7\u3001\u968f\u673a\u8bbf\u95ee\u3002\u9ad8\u7ea7 I\/O \u95ee\u9898\uff1a\u538b\u7f29\u3001\u9ad8\u901f\u7f13\u51b2\u3001\u5206\u89e3\u3001\u4e32\u884c\u5316\u3001\u83b7\u53d6\u6587\u4ef6\u4fe1\u606f\u3002<\/p>\n<p style=\"margin: 1em 0px;\">\u52a0\u901f I\/O \u7684\u57fa\u672c\u89c4\u5219\uff1a\u907f\u514d\u8bbf\u95ee\u78c1\u76d8\uff1b\u907f\u514d\u8bbf\u95ee\u5e95\u5c42\u64cd\u4f5c\u7cfb\u7edf\uff1b\u907f\u514d\u65b9\u6cd5\u8c03\u7528\uff1b\u907f\u514d\u9010\u4e2a\u5904\u7406\u5b57\u8282\u548c\u5b57\u7b26\u3002\u8fd9\u4e9b\u89c4\u5219\u5f53\u7136\u4e0d\u80fd\u5904\u5904\u90fd\u907f\u5f00\uff0c\u5426\u5219\u5c31\u6ca1\u6709\u5b9e\u9645 I\/O \u4e86\u3002<\/p>\n<ul style=\"padding-left: 1rem; margin-left: 1rem; font-size: 0.9rem; list-style-type: disc;\">\n<li>\n<section>\u907f\u514d\u8bbf\u95ee\u78c1\u76d8<\/section>\n<\/li>\n<li>\n<section>\u907f\u514d\u8bbf\u95ee\u5e95\u5c42\u64cd\u4f5c\u7cfb\u7edf<\/section>\n<\/li>\n<li>\n<section>\u907f\u514d\u65b9\u6cd5\u8c03\u7528<\/section>\n<\/li>\n<li>\n<section>\u907f\u514d\u4e2a\u522b\u5904\u7406\u5b57\u8282\u548c\u5b57\u7b26<\/section>\n<\/li>\n<\/ul>\n<h2 style=\"padding: 1px 12.5px; color: #ffffff; margin: 1.2em 0px 1em; border-radius: 4px; display: inline-block; background-color: #4870ac; font-size: 1.3em;\">\u4e8c\u3001\u7528\u7f13\u51b2\u51cf\u5c11\u8bfb\u5199\u6b21\u6570<\/h2>\n<p style=\"margin: 1em 0px;\">\u5bf9 1 MB \u8f93\u5165\u6587\u4ef6\uff0c\u4e09\u79cd\u8bfb\u6cd5\u7684\u6267\u884c\u65f6\u95f4\u5dee\u8ddd\u5f88\u5927\u3002\u6700\u6162\u548c\u6700\u5feb\u5927\u7ea6\u662f 17 \u6bd4 1\u3002\u5de8\u5927\u52a0\u901f\u5e76\u4e0d\u7b49\u4e8e\u6c38\u8fdc\u8be5\u7528\u201c\u81ea\u5df1\u505a\u7f13\u51b2\u201d\u7684\u7b2c\u4e09\u79cd\uff1a\u6587\u4ef6\u7ed3\u675f\u5904\u7406\u7a0d\u4e0d\u5c0f\u5fc3\u5c31\u4f1a\u5199\u9519\uff0c\u53ef\u8bfb\u6027\u4e5f\u4e0d\u5982\u5305\u88c5\u6d41\u3002\u65b9\u6cd5 2 \u5bf9\u591a\u6570\u5e94\u7528\u624d\u662f\u201c\u6b63\u786e\u201d\u9009\u62e9\u3002<\/p>\n<table style=\"display: table; text-align: left; overflow: auto; border-collapse: collapse; margin: 1.4em auto; max-width: 100%; table-layout: fixed; overflow-wrap: break-word; word-break: break-all;\" width=\"800\">\n<thead>\n<tr>\n<th style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top; text-align: center; font-weight: bold; color: #4870ac; background: #f7f7f7;\">\u65b9\u6cd5<\/th>\n<th style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top; text-align: center; font-weight: bold; color: #4870ac; background: #f7f7f7;\">\u505a\u6cd5<\/th>\n<th style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top; text-align: center; font-weight: bold; color: #4870ac; background: #f7f7f7;\">\u7ea6 1MB \u8017\u65f6<\/th>\n<th style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top; text-align: center; font-weight: bold; color: #4870ac; background: #f7f7f7;\">\u4f18\u70b9 \/ \u7f3a\u70b9<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">1<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">FileInputStream.read() \u6bcf\u6b21\u4e00\u5b57\u8282\uff0c\u65e0\u7f13\u51b2<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">6.9 \u79d2<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">\u7f16\u7801\u7b80\u5355\uff0c\u9002\u5408\u5c0f\u6587\u4ef6\uff1b\u5e95\u5c42\u8c03\u7528\u6781\u591a\uff0c\u4e0d\u9002\u5408\u5927\u6587\u4ef6<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">2<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">BufferedInputStream \u5305\u88c5\u540e\u518d\u9010\u5b57\u8282\u8bfb<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">0.9 \u79d2<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">\u907f\u514d\u6bcf\u4e2a\u5b57\u8282\u90fd\u6253\u5230\u5e95\u5c42\uff1b\u5360\u7528\u5c11\u91cf\u5185\u5b58<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">3<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">FileInputStream.read(buf) \u8bfb\u5165\u81ea\u5907\u7f13\u51b2\u533a<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">0.4 \u79d2<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">\u6700\u5feb\uff1b\u7f16\u7801\u7a0d\u590d\u6742\u3001\u53ef\u8bfb\u6027\u5dee<\/td>\n<\/tr>\n<tr>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">4<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">\u6309\u6587\u4ef6\u957f\u5ea6\u4e00\u6b21\u8bfb\u5b8c\u5168\u6587\u4ef6<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">\u53d6\u51b3\u4e8e\u5185\u5b58<\/td>\n<td style=\"border: 1px solid #d9dfe4; padding: 9px 12px; font-size: 0.75em; line-height: 22px; vertical-align: top;\">\u5e95\u5c42\u8bfb\u53d6\u6700\u5c11\uff1b\u5927\u6587\u4ef6\u53ef\u80fd\u8017\u5c3d\u5185\u5b58<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin: 1em 0px;\">\u65b9\u6cd5 2 \u548c 3 \u90fd\u7528\u4e86\u7f13\u51b2\uff1a\u5927\u5757\u4ece\u78c1\u76d8\u8bfb\u5165\uff0c\u518d\u6309\u5b57\u8282\u6216\u5b57\u7b26\u8bbf\u95ee\u3002<strong style=\"color: #4870ac;\">\u7f13\u51b2<\/strong>\u662f\u52a0\u901f I\/O \u7684\u57fa\u672c\u6280\u672f\u3002\u5b57\u8282\u7528 <code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">BufferedInputStream<\/code>\uff0c\u5b57\u7b26\u7528 <code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">BufferedReader<\/code>\u3002\u5178\u578b Java \u7f13\u51b2\u533a\u662f 1024 \u6216 2048 \u5b57\u8282\uff1b\u518d\u52a0\u5927\u7ea6\u80fd\u518d\u5feb 5%\uff5e10%\uff0c\u6bd4\u91cd\u5f88\u5c0f\u3002<\/p>\n<h2 style=\"padding: 1px 12.5px; color: #ffffff; margin: 1.2em 0px 1em; border-radius: 4px; display: inline-block; background-color: #4870ac; font-size: 1.3em;\">\u4e09\u3001\u65b9\u6cd5 1\uff1a\u9010\u5b57\u8282 read<\/h2>\n<p style=\"margin: 1em 0px;\"><code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">FileInputStream<\/code> \u7684 <code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">read()<\/code> \u6bcf\u6b21\u53d6\u4e0b\u4e00\u4e2a\u5b57\u8282\uff0c\u4f1a\u89e6\u53d1\u5927\u91cf\u5e95\u5c42\u8fd0\u884c\u65f6\u8c03\u7528\u3002<\/p>\n<pre style=\"overflow: auto hidden; word-break: normal; white-space: pre; tab-size: 2; border-radius: 5px; line-height: 2; margin: 1em 0.5em; padding: 0.5em; box-shadow: rgba(0, 0, 0, 0.55) 0px 1px 5px; font-size: 12px; background: #002b36; max-width: 100%; overflow-wrap: normal;\"><code class=\"hljs\" style=\"word-break: normal; white-space: nowrap; tab-size: 2; font-size: 12px; font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; display: block; overflow-x: auto; margin: 0.5em; padding: 3px 5px; color: #93a1a1; background: #002b36; overflow-wrap: normal;\">import java.io.*;\npublic class intro1 {\n    public static void main(String args[]) {\n        if (args.length != 1) {\n            System.err.println(\"missing filename\");\n            System.exit(1);\n        }\n        try {\n            FileInputStream fis = new FileInputStream(args[0]); \/\/ \u5efa\u7acb\u6307\u5411\u6587\u4ef6\u7684\u8bfb\u5199\u6d41\n            int cnt = 0;\n            int b;\n            while ((b = fis.read()) != -1) { \/\/ \u6bcf\u6b21\u8bfb\u53d6\u4e00\u4e2a\u5b57\u8282\n                if (b == '\\n')\n                    cnt++;\n            }\n            fis.close();\n            System.out.println(cnt);\n        } catch (IOException e) {\n            System.err.println(e);\n        }\n    }\n}<\/code><\/pre>\n<h2 style=\"padding: 1px 12.5px; color: #ffffff; margin: 1.2em 0px 1em; border-radius: 4px; display: inline-block; background-color: #4870ac; font-size: 1.3em;\">\u56db\u3001\u65b9\u6cd5 2\uff1aBufferedInputStream<\/h2>\n<p style=\"margin: 1em 0px;\">\u628a\u6587\u4ef6\u5b57\u8282\u5757\u8bfb\u5165\u7f13\u51b2\u533a\uff0c\u518d\u6bcf\u6b21\u53d6\u4e00\u4e2a\u5b57\u8282\u3002\u6bcf\u586b\u6ee1\u4e00\u6b21\u7f13\u51b2\u624d\u8bbf\u95ee\u4e00\u6b21\u5e95\u5c42\u5b58\u50a8\u3002<\/p>\n<pre style=\"overflow: auto hidden; word-break: normal; white-space: pre; tab-size: 2; border-radius: 5px; line-height: 2; margin: 1em 0.5em; padding: 0.5em; box-shadow: rgba(0, 0, 0, 0.55) 0px 1px 5px; font-size: 12px; background: #002b36; max-width: 100%; overflow-wrap: normal;\"><code class=\"hljs\" style=\"word-break: normal; white-space: nowrap; tab-size: 2; font-size: 12px; font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; display: block; overflow-x: auto; margin: 0.5em; padding: 3px 5px; color: #93a1a1; background: #002b36; overflow-wrap: normal;\">import java.io.*;\npublic class intro2 {\n    public static void main(String args[]) {\n        if (args.length != 1) {\n            System.err.println(\"missing filename\");\n            System.exit(1);\n        }\n        try {\n            FileInputStream fis = new FileInputStream(args[0]);\n            BufferedInputStream bis = new BufferedInputStream(fis); \/\/ \u6587\u4ef6\u6d41\u6307\u5411\u7f13\u51b2\u533a\n            int cnt = 0;\n            int b;\n            while ((b = bis.read()) != -1) { \/\/ \u6309\u5757\u8bfb\u5165\u7f13\u51b2\u533a\uff0c\u518d\u6bcf\u6b21\u53d6\u4e00\u4e2a\u5b57\u8282\n                if (b == '\\n')\n                    cnt++;\n            }\n            bis.close();\n            System.out.println(cnt);\n        } catch (IOException e) {\n            System.err.println(e);\n        }\n    }\n}<\/code><\/pre>\n<h2 style=\"padding: 1px 12.5px; color: #ffffff; margin: 1.2em 0px 1em; border-radius: 4px; display: inline-block; background-color: #4870ac; font-size: 1.3em;\">\u4e94\u3001\u65b9\u6cd5 3\uff1a\u76f4\u63a5\u7f13\u51b2<\/h2>\n<p style=\"margin: 1em 0px;\">\u7528 <code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">fis.read(buf)<\/code> \u628a\u5b57\u8282\u5757\u76f4\u63a5\u8bfb\u8fdb <code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">buf<\/code>\uff0c\u518d\u5728\u6570\u7ec4\u91cc\u626b\u6362\u884c\u3002\u901f\u5ea6\u6700\u5feb\uff0c\u4f46\u8981\u81ea\u5df1\u5904\u7406\u8bfb\u5165\u957f\u5ea6 <code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">n<\/code>\u3002<\/p>\n<pre style=\"overflow: auto hidden; word-break: normal; white-space: pre; tab-size: 2; border-radius: 5px; line-height: 2; margin: 1em 0.5em; padding: 0.5em; box-shadow: rgba(0, 0, 0, 0.55) 0px 1px 5px; font-size: 12px; background: #002b36; max-width: 100%; overflow-wrap: normal;\"><code class=\"hljs\" style=\"word-break: normal; white-space: nowrap; tab-size: 2; font-size: 12px; font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; display: block; overflow-x: auto; margin: 0.5em; padding: 3px 5px; color: #93a1a1; background: #002b36; overflow-wrap: normal;\">import java.io.*;\npublic class intro3 {\n    public static void main(String args[]) {\n        if (args.length != 1) {\n            System.err.println(\"missing filename\");\n            System.exit(1);\n        }\n        try {\n            FileInputStream fis = new FileInputStream(args[0]);\n            byte buf[] = new byte[2048];\n            int cnt = 0;\n            int n;\n            while ((n = fis.read(buf)) != -1) { \/\/ \u76f4\u63a5\u8bfb\u5165\u5b57\u8282\u5757\u5230 buf\n                for (int i = 0; i < n; i++) {\n                    if (buf[i] == '\\n')\n                        cnt++;\n                }\n            }\n            fis.close();\n            System.out.println(cnt);\n        } catch (IOException e) {\n            System.err.println(e);\n        }\n    }\n}<\/code><\/pre>\n<h2 style=\"padding: 1px 12.5px; color: #ffffff; margin: 1.2em 0px 1em; border-radius: 4px; display: inline-block; background-color: #4870ac; font-size: 1.3em;\">\u516d\u3001\u65b9\u6cd5 4\uff1a\u7f13\u51b2\u6574\u4e2a\u6587\u4ef6<\/h2>\n<p style=\"margin: 1em 0px;\">\u6781\u7aef\u60c5\u51b5\uff1a\u5148\u53d6\u6587\u4ef6\u957f\u5ea6\uff0c\u518d\u4e00\u6b21\u8bfb\u5b8c\u3002\u6587\u4ef6\u53d8\u6210\u5b57\u8282\u6570\u7ec4\uff0c\u5f88\u65b9\u4fbf\uff1b\u95ee\u9898\u662f\u5de8\u5927\u6587\u4ef6\u53ef\u80fd\u6ca1\u6709\u8db3\u591f\u5185\u5b58\u3002<\/p>\n<pre style=\"overflow: auto hidden; word-break: normal; white-space: pre; tab-size: 2; border-radius: 5px; line-height: 2; margin: 1em 0.5em; padding: 0.5em; box-shadow: rgba(0, 0, 0, 0.55) 0px 1px 5px; font-size: 12px; background: #002b36; max-width: 100%; overflow-wrap: normal;\"><code class=\"hljs\" style=\"word-break: normal; white-space: nowrap; tab-size: 2; font-size: 12px; font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; display: block; overflow-x: auto; margin: 0.5em; padding: 3px 5px; color: #93a1a1; background: #002b36; overflow-wrap: normal;\">import java.io.*;\npublic class readfile {\n    public static void main(String args[]) {\n        if (args.length != 1) {\n            System.err.println(\"missing filename\");\n            System.exit(1);\n        }\n        try {\n            int len = (int)(new File(args[0]).length());\n            FileInputStream fis = new FileInputStream(args[0]);\n            byte buf[] = new byte[len]; \/\/ \u5efa\u7acb\u76f4\u63a5\u7f13\u51b2\n            fis.read(buf);              \/\/ \u8bfb\u53d6\u6574\u4e2a\u6587\u4ef6\n            fis.close();\n            int cnt = 0;\n            for (int i = 0; i < len; i++) {\n                if (buf[i] == '\\n')\n                    cnt++;\n            }\n            System.out.println(cnt);\n        } catch (IOException e) {\n            System.err.println(e);\n        }\n    }\n}<\/code><\/pre>\n<h2 style=\"padding: 1px 12.5px; color: #ffffff; margin: 1.2em 0px 1em; border-radius: 4px; display: inline-block; background-color: #4870ac; font-size: 1.3em;\">\u4e03\u3001\u7ec8\u7aef\u8f93\u51fa\u4e0e\u53c2\u8003<\/h2>\n<p style=\"margin: 1em 0px;\">\u7f13\u51b2\u7684\u53e6\u4e00\u9762\u662f\u5411\u7a97\u53e3\u7ec8\u7aef\u8f93\u51fa\u6587\u672c\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c<code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">System.out<\/code>\uff08\u4e00\u4e2a <code style=\"font-family: Menlo, Monaco, Consolas, 'Liberation Mono', 'Roboto Mono', 'Courier New', 'Microsoft YaHei', monospace; color: #4870ac; font-size: 0.9em; font-weight: normal; overflow-wrap: break-word; padding: 2px 4px; border-radius: 3px; margin: 2px; background-color: #f6f8fa; word-break: break-all;\">PrintStream<\/code>\uff09\u662f\u884c\u7f13\u51b2\u7684\uff1a\u9047\u5230\u6362\u884c\u7b26\u540e\u624d\u63d0\u4ea4\u8f93\u51fa\u7f13\u51b2\u533a\u3002<\/p>\n<p style=\"margin: 1em 0px;\">\u8f6c\u8d34\u6765\u6e90\uff1a<a href=\"http:\/\/blog.csdn.net\/yihu0817\/article\/details\/41965589\">http:\/\/www.uml.org.cn\/zjjs\/201006121.asp<\/a>\u3000<a href=\"http:\/\/blog.csdn.net\/Dbzen\/archive\/2008\/11\/22\/3350325.aspx\">http:\/\/blog.csdn.net\/Dbzen\/archive\/2008\/11\/22\/3350325.aspx<\/a><\/p>\n<blockquote style=\"display: block; font-size: 0.9em; border-left: 3px solid #4870ac; padding: 0.5em 1em; margin: 0px; background: #f6f8fa; color: #40464f;\">\n<p style=\"margin: 1em 0px;\"><strong style=\"color: #4870ac;\">\u4e00\u53e5\u8bdd\u603b\u7ed3\uff1aI\/O \u8981\u5feb\uff0c\u5148\u51cf\u5c11\u78c1\u76d8\u548c\u7cfb\u7edf\u8c03\u7528\uff1a\u4f18\u5148 Buffered \u5305\u88c5\u6d41\uff0c\u5fc5\u8981\u65f6\u81ea\u5907\u7f13\u51b2\u533a\uff1b\u6574\u6587\u4ef6\u8bfb\u5165\u53ea\u9002\u5408\u5185\u5b58\u88c5\u5f97\u4e0b\u7684\u60c5\u51b5\u3002<\/strong><\/p>\n<\/blockquote>\n<\/section>\n","protected":false},"excerpt":{"rendered":"<p>\u672c\u6587\u591a\u6570\u6280\u5de7\u56f4\u7ed5\u78c1\u76d8\u6587\u4ef6 I\/O\uff0c\u4f46\u540c\u6837\u9002\u5408\u7f51\u7edc I\/O \u548c\u7a97\u53e3\u8f93\u51fa\u3002\u5148\u770b\u5e95\u5c42\u8bfb\u5199\uff0c\u518d\u8c08\u538b\u7f29\u3001\u683c\u5f0f\u5316\u548c\u4e32\u884c\u5316\u7b49 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[22],"tags":[41],"_links":{"self":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts\/580"}],"collection":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=580"}],"version-history":[{"count":3,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts\/580\/revisions"}],"predecessor-version":[{"id":584,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts\/580\/revisions\/584"}],"wp:attachment":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=580"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=580"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=580"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}