{"id":86728,"date":"2020-05-14T02:37:47","date_gmt":"2020-05-13T18:37:47","guid":{"rendered":"http:\/\/4563.org\/?p=86728"},"modified":"2020-05-14T02:37:47","modified_gmt":"2020-05-13T18:37:47","slug":"%e4%b8%8d%e6%87%82%e5%b0%b1%e9%97%ae%ef%bc%8c-java-%e4%b8%ad%e6%96%87%e4%bb%b6%e5%a4%8d%e5%88%b6%e9%80%9f%e5%ba%a6%e7%9a%84%e9%97%ae%e9%a2%98%e3%80%82","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=86728","title":{"rendered":"\u4e0d\u61c2\u5c31\u95ee\uff0c Java \u4e2d\u6587\u4ef6\u590d\u5236\u901f\u5ea6\u7684\u95ee\u9898\u3002"},"content":{"rendered":"
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\u4e0d\u61c2\u5c31\u95ee\uff0c Java \u4e2d\u6587\u4ef6\u590d\u5236\u901f\u5ea6\u7684\u95ee\u9898\u3002 <\/h1>\n

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\u8cc7\u6df1\u5927\u4f6c : zhao1014 <\/span> <\/i> 5<\/span> <\/div>\n
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\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n

public class copy { public static void main(String[] args) throws IOException { long s = System.currentTimeMillis();<\/p>\n

    FileInputStream fis = new FileInputStream(\"C:\\Users\\ZZY\\Desktop\\JavaNote\\02-Java \u8bed\u8a00\u8fdb\u9636\\\u539f\u7406\u56fe\\\u54c8\u5e0c\u8868.png\");     FileOutputStream fos = new FileOutputStream(\"C:\\Users\\ZZY\\Desktop\\\u54c8\u5e0c\u8868.png\");      byte[] bytes = new byte[1024];     int len = 0;     while((len = fis.read()) != -1){         fos.write(bytes,0,len);     }           fos.close();     fis.close();      long e =  System.currentTimeMillis();     System.out.println(\"\u6587\u4ef6\u8f93\u51fa\u8017\u65f6\" + (e-s) + \"\u6beb\u79d2\" ); } <\/code><\/pre>\n
}<\/p>\n
\u5b57\u8282\u6570\u7ec4\u957f\u5ea6\u8bbe\u7f6e\u4e3a 1024 \u662f\u7528\u65f6 3295 \u957f\u5ea6\u4e3a 10240000 \u65f6\u7528\u65f6 2942 \u957f\u5ea6\u4e3a 1024000000 \u65f6\u7528\u65f6 3485<\/p>\n
\u56fe\u7247\u5927\u5c0f\u662f 52mb<\/p>\n
\u4e3a\u4ec0\u4e48\u6570\u7ec4\u957f\u5ea6\u53d8\u5927\u4e86\uff0c\u8bfb\u53d6\u65f6\u95f4\u53cd\u800c\u662f\u957f\u2192\u77ed\u2192\u66f4\u957f\u5462\uff1f<\/p>\n<\/p><\/div>\n
 \u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (12<\/span>)        <\/div>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : zhao1014 <\/span>  <\/div>\n
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                                                                 \u683c\u5f0f\u4e71\u4e86\u4e0d\u597d\u610f\u601d\uff0c\u5c06\u5c31\u770b\u4e0b                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : misaka19000 <\/span>  <\/div>\n
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                                                                 \u4e5f\u8bb8\u662f\u8d85\u8fc7\u4e86\u78c1\u76d8\u6216\u8005\u5185\u5b58\u6216\u8005 CPU \u7684\u7f13\u5b58\u6216\u8005\u8d85\u8fc7\u4e86\u78c1\u76d8\u6216\u8005 CPU \u7684\u5feb\u5927\u5c0f                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : xupefei <\/span>  <\/div>\n
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                                                                 \u4e00\u4e2a\u7c07\u662f 4096 \u5b57\u8282\u3002
    1024 \u7684 buffer \u5728\u6ca1\u6709 read ahead \u7684\u65f6\u5019\u662f\u6d6a\u8d39\u78c1\u76d8 IO \u3002
    \u4e3b\u591a\u8bd5\u51e0\u4e2a 4096 \u7684\u500d\u6570\uff1f                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : xupefei <\/span>  <\/div>\n
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                                                                 \u6211\u4ed4\u7ec6\u770b\u4e86\u770b\u4ee3\u7801\uff0cfis.read \u6bcf\u6b21\u8bfb\u4e00\u4e2a\u5b57\u8282\uff0c\u4f60\u8bbe\u7f6e\u7684 buffer \u5927\u5c0f\u6709\u610f\u4e49\u5417                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : whitev2 <\/span>  <\/div>\n
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                                                                 Files.copy() \u4e0d\u9999\u4e48\uff1f                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : zhao1014 <\/span>  <\/div>\n
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                                                                 @xupefei \u65b0\u624b\u4e0a\u8def\uff0c\u521a\u521a\u5b66\u5230\u8fd9\u91cc                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : zhao1014 <\/span>  <\/div>\n
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                                                                 @whitev2 \u5c31\u662f\u4e0d\u592a\u7406\u89e3\u4e3a\u4ec0\u4e48\u4f1a\u8fd9\u6837                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : zhao1014 <\/span>  <\/div>\n
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                                                                 @xupefei \u6211\u6ca1\u6ce8\u610f\uff01\u592a\u8111\u762b\u4e86\u3002\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : zhao1014 <\/span>  <\/div>\n
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                                                                 @xupefei \u6211\u628a\u4ee3\u7801\u6539\u4e86\uff0c1024 \u65f6\u7528\u65f6 8 \u6beb\u79d2\uff0c
    102400000 \u7528\u65f6 175 \u6beb\u79d2\uff0c\u4f60\u8bf4\u7684\u7c07\u6211\u8fd8\u4e0d\u592a\u61c2\u5e94\u8be5\u662f\u6211\u6ca1\u5b66\u5230\u7684\u5730\u65b9\uff0c\u6211\u67e5\u67e5\u8d44\u6599\u5b66\u4e60\u4e00\u4e0b\u3002\u8c22\u8c22\u56de\u7b54\uff01                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : zhao1014 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @xupefei \u6d4b\u8bd5 4096 \u548c 409600000 \u7684\u65f6\u5019\u4e5f\u662f\u5927\u7684\u5b57\u8282\u6570\u7ec4\u8bfb\u5199\u7684\u901f\u5ea6\u6162\uff0c\u4f46\u662f 4096 \u6bd4 1024 \u5feb\u5f88\u591a\uff0c40960 \u6bd4 4096 \u5feb\u4e00\u70b9\uff0c\u6570\u7ec4\u8fc7\u5927\u8bfb\u5199\u901f\u5ea6\u53cd\u800c\u4f1a\u6162\u4e86\uff0c\u4e0d\u592a\u7406\u89e3\u4e3a\u4ec0\u4e48\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : doudouwu <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @zhao1014 \u4f60\u5f97\u5148\u786e\u5b9a\u4f60\u8fd9\u6837\u80fd\u628a\u56fe\u7247 copy \u5230\u53e6\u4e00\u4e2a\u6587\u4ef6\u518d\u786e\u5b9a\u5176\u4ed6\u7684                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
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     \u8cc7\u6df1\u5927\u4f6c : doudouwu <\/span>  <\/div>\n
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                                                                 \u778e\u4e86\uff0c\u6ca1\u770b\u5230\u66f4\u6b63                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n","protected":false},"excerpt":{"rendered":"
    \u4e0d\u61c2\u5c31\u95ee\uff0c Java \u4e2d\u6587\u4ef6\u590d\u5236\u901f…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/86728"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=86728"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/86728\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=86728"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=86728"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=86728"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}