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简单想法

446 Responses to "简单想法"

• ideawu 2011-12-26 at 17:57:47
  grep 中的 "+" 要转义, 而且不需要 -e 参数 Reply
• ideawu 2011-12-14 at 17:25:14
  Java Double Check Lock 和 Lazy Initialization Holder
  
  Java Double Check Lock
  
  

  
  public class Foo{
      private static volatile Foo instance;
  
      public static Foo getInstantce() {
          if(instance == null){
              synchronized(Foo.class){
                  if(instance == null){
                      instance = new Foo();
                  }
              }
          }
          return  instance;
      }
  }
  

  
  
  Lazy Initialization Holder
  
  

  
  public class Foo {
      private static class FooHolder {
          static final Foo foo = new Foo();
      }
      public static Foo getInstantce() {
          return FooHolder.foo;
      }
  }
  

  
  Reply
• ideawu 2011-12-07 at 11:57:55
  php_sapi_name() == ‘cli’ Reply
• ideawu 2011-11-18 at 12:38:10
  要小心IE浏览器的AJAX缓存. Reply
• ideawu 2011-11-15 at 15:21:48
  UTF-8转义和反转义(中文转义为反斜杠x"\x"编码, 二进制):
  
  echo str_replace(‘%’, ‘\x’, urlencode(‘你好’));
  echo "\n";
  echo urldecode(str_replace(‘\x’, ‘%’, ‘\xE4\xBD\xA0\xE5\xA5\xBD’));
  echo "\n";
  
  而unicode编码(\u)则是 json_encode(‘你好’) =: ‘\u4f60\u597d’ Reply
• ideawu 2011-11-09 at 15:59:09
  连续两个grep有时会等很久才有输出, 估计是管道缓冲的问题. 如: tail -f a | grep a | grep b, 用 grep 的 –line-buffered 选项试试.
  
  ulimit
  -p <缓冲区大小> 　指定管道缓冲区的大小，单位512字节。 Reply
• ideawu 2011-11-09 at 14:47:18
  状态的英语单词读音: status ['stetəs] Reply
• ideawu 2011-11-07 at 14:57:54
  vi diff:
  
  vi -d a.txt b.txt
  
  或者先打开 a.txt, 然后
  :vertical diffsplit b.txt Reply
• ideawu 2011-11-01 at 14:52:45
  用JSON文本传递二进制数据, 必须先把二进制数据转成文本才能传递. Reply
• ideawu 2011-11-01 at 14:25:55
  PHP的json_encode()函数不能处理二进制数据, 所以, 图片本身是不能被json_encode()的! Reply

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